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Missing - Transmission Overload Protection Switch an issue?

mb280sel1985

E500E Enthusiast
Member
The EPC has 3 listing for item# 303 - Transmission Overload Protector B1 - part# A 002 545 45 14.

The last one with the following footnote:

"Inapplicable to vehicles with catalyst"

Now my question is of course:

Does my car actually have this part installed? (Porche part actually).
Because, my car does have the SA Codes 620 and 823.. (the vehicle is equiped with catalyst technique).

The reason why I'm even bothering is because I found an "old paper" (see picture) about this switch, in the desperate need of figuring out why my engine is cutting at 4000 rpms - sometimes 4800 rpms and 5500 rpms - at WOT and mostly after the following scenario:

1. kickdown from 3 to 2
2. WOT at 4000 rpms (sometimes 4800 rpms)
3. Cuts/misses and is locked at 4000 rpms
4. Easying the pedal - flooring it again - makes it go higher on the rpms

Or,

1. kickdown from 3 to 2
2. Flooring and hitting 5500 rpms
3. Hesitates - Takes about 1- 1.5 seconds to shift - with a fe

..The old paper printout says that "In case of complaints of misfiring at high vehicle speed, the overload protection switch and its wiring must be checked."


My transmission:

-Overhauled in 2010

-March 2011 - found nowhere to connect vacuum line - either item# 920 or 935 - not sure (see picture) - for the electric change-over valve (don't know what that is..) - quick fix: closed the hose - vehicle became somewhat calmer

-Neutral Safety Switch - been thinking about replacing this for a while now - I have the ASR light constantly on - now to the point where I cannot reset it by turning over. I have had the engine start only 1 time without the ASR light coming on in the past 3 months. This one time, and also from earlier experience, my rpms are LOW - about 450-500 rpms. But then sometimes it may idle steadily at 650 rpms. I think this is a familiar problem that many others have experienced too - at least what I've read.



Other than that:

-new plugs
-wires ok
-coils, caps and rotors checked and cleaned
-new mass
-new O2 sensor
-new upper wiring harness
-overhauled in 2010
-new fuel pump relay - no difference
 

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I am also worried about the fuel pressure regulator.. All the below applies to my car!

-fuel pressure regulator - not checked (bought but not installed)
May cause whining fuel pumps?
May cause black smoke from exhaust due to leaking gas into engine oil?
May cause oil leak?
May cause cylinder 8 (last on the rail) to become black?
May cause misfires and rich conditions?
May cause slight surging near idle?
Faulty if rail pressure is over 100 psi?

From what I read around, in general this part may go bad and cause the last cylinder on the fuel rail to run rich - which showed when I had my plugs checked recently. All 8 were replaced - there was especially 1 plug that was contaminated - probably due to running rich..? It may also be the cause of misfires and slight surging on idle I'm experiencing - or maybe not?
 
Dumb question: Have you pulled codes (from all systems) to see if there are any related to the overload protection switch? There will be specific codes stored if the switch is not working as expected.

:detective:
 
Also - based on a previous member's experience - please post the part number of the EZL currently installed in your car.

:banana2:
 
Also - based on a previous member's experience - please post the part number of the EZL currently installed in your car.

:banana2:

Regarding the EZL - I got it confirmed in some other thread that it is okay. I post the part no shortly, so it can be checked off
 
Dumb question: Have you pulled codes (from all systems) to see if there are any related to the overload protection switch? There will be specific codes stored if the switch is not working as expected.

:detective:

You see, this is my problem right now. I've had the ASR pulled, and it returned a fault with the idle contact switch. Later I had an indy MB specialist pull codes, but got issues with the CAN bus - the upper wiring was way overdue, so that has just been replaced. Following that, we couldn't get enough info through the hand held tester he has - something called "Basicdiagnosis SBD-102" - dunno if it's a descent tool or not.. But he was determined on getting it checked with his Star Diagnosis, but has had its batteries die on him, not being able to use it for the past 5-6 weeks.

I have a flash code reader - one of those from eBay with the german flag and a big star on it. I'm not quite sure how to test correctly with it, or if it will do the job - enough to get all the factors on the table.

Could you describe how I can check if the overload protection switch is faulty, using the flash code reader? So it will definitely throw a code if it is bad?
 
For basic instructions on how to use the blinker box, click here.

Plug your blink code reader in, connected to +12v, ground, and socket #17 to check the EZL codes. That's where I'd start, anyway. Click this link, see pages 22-23 (for the EZL). Other systems are described in the first few pages. If you can pull & clear EZL codes, then move on to checking/clearing LH, E-GAS, BM, ABS/ASR, and DM. You can skip HVAC and SRS as these don't affect engine operation.


:detective:
 
Ok, so I have read codes with this: http://www.ebay.com/itm/Mercedes-co...L600-DIY-W140-124-/320779565305#ht_927wt_1140
- see picture below -

I'm unsure I went about correctly. Here is what I did:

- Pre-note -
The flash code reader has a black, green and yellow wire. Since I didn't find my docs I figured the black is ground, the green is positive, and the yellow is to be connected to the different readout pins.


- My procedure -
1. I put the ignition in ON position - firing up all the check lamps
2. Looking at the diagnostics socket in the engine compartment - standing on the left side of my car - I figure from my location the pins have the following order:

pin #1: from bottom right - GROUND
pin #3: from bottom left - +/power
pin #4: 1st pin (from right) on the 2nd row (from bottom) - LH
pin #17: 1st pin on (from right) on the 4th row (from bottom) - EZL

The other pins are then given taking the above description - also the pins that are not used do not have metal connector in them I figure.

- The diagnose -
1. I put yellow wire into pin #17 - the EZL - as you recommended starting with - CODE: 8

Got a rather weak red light. Withouth pressing the button or moving the tester from its connected pins, I receive 8 blinks. NOTE: The 8 blinks shouldn't have come on before I'd pressed the red button right?? - at least according to the step-by-step instructions you posted GXSR. Now, looking at the reader (see picture) it does actually say RESET BUTTON - dunno if it does the 2-3 second pressing by its own or not..

2. I tried to press the red button for 2-3 seconds - hoping to read the next code on the pin, nothing happens - just a steady red light (still weak).

3. Well, I decided to clear the code, by pressing and holding the red button for 8-10 seconds.

4. Now I disconnected the yellow wire, and reconnected it again into the same pin (#17). I tried to press the red button for 2-3 seconds again, this time to see if the CODE 8 had been cleared - nothing happens - just a steady red light (still weak) - I guess the code got cleared..

I continued to all the pins #4, #7, #8, #6, and #19. There were no blinks on these.

I did notice however, that all the pins, except pin #17 and #6 had quite a bit stronger red light, when connecting the reader to them.

- To sum up -
After clearing the code, I still have the ASR lamp showing. It has been ON constant for the past 2 months - only once I was able to start the engine with the light off - restarting it, the ASR came back on. Even the indy guy was unable to reset the ASR .. something .. with his HHT.

So I got only these 8 blinks from the pin #17. Is it correct that this is actually the "Transmission overload protection switch (S65) does not close" ??

If so - SPOT ON!! But Is really this switch supposed to make the ASR lamp light up?
 

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Hm, is the EZL I have correct?

From the EPC - when entering my VIN# WDB 124 036 1B92 09XX, I get the following listing for EZL (Ignition Control Module):

-A 009 545 63 32 - Replaced by -> A 015 545 61 32 - use with = +002.A 000 158 57 03 (type of ignition coil)
-A 010 545 03 32 - Replaced by -> A 012 545 61 32 - use with = +001 A 000 158 57 03 or A 000 158 58 03 (type of ignition coil)
-A 015 545 61 32 - Optional with = A 015 545 62 32
-A 015 545 62 32 - Optional with = A 015 545 61 32

Obviously the last one is the best alternative for my car.

But mine is A 014 545 43 32!!
 
Ok, read the posts. I understand the later EPC only lists the later EZL part numbers (replacement parts).

So my EZL 014 545 43 32 is original for my build - 02/93 - and is correct.

Is my EZL a problem part?

Also, does my procedure and my result from diagnose above seem correct?

If, so - what to do next..
 
EZL 014-545-43-32 is correct for a 5.0L engine.

I am not sure you had the code reader connected properly. The colors of the wires are non-standard. If you can't find the instructions included with it, you'll need to validate with the seller if you had it plugged in correctly. The LED should not light up unless you hold down the button, or when it's blinking codes. Any system which has no codes will return a single blink. If that is not what you experienced, either it was not connected properly, or connected to the wrong sockets in the 38-pin port. What you describe above is NOT how it should have worked.

Click here for a video of what it should look like, shown on a 300E (same concept, different size diagnostic ports). I'd repeat the test until you are certain you are pulling codes, and clearing them. When all the codes are cleared, the dash lights should go off (after power is cycled off).

If you can clear EZL codes (i.e., if there really is code #8) it should go back to 1 blink when you check it again. But if you drive the car and this code re-appears, then it's a valid code that should be investigated and fixed.


:banana2:
 
Tried again today. I most certainly did it wrong. The green is ground, yellow is 12V+, and the black is for the diagnostics pins, according to the instructions I found on the disc that came with it. I think Jim F would know, since he wrote them.

Well, no luck whatsoever. Connected black wire to 17, 4, 7, 8 and 6, but didn't get any codes.

What happened was not like you described it should react. When connecting up and putting ignition to ON position, I got no red light before pressing the button (this is correct). But right when pressing it, a very short (100 ms) signal. Releasing after 3 seconds gave no reactions at all. On two of the pins I could get a very fast, uncertain nuber of blinks (2 or 3). But they where so brief that it couldn't possibly'd been designed that way.

I'm frustrated now :(

Is there a reliable - not so expensive flash code reader You would recommend? Maybe something wrong with the reader.

I think I will open up the "computer" box to see if there are any fuses blown. Would a blown fuse inside the module box make any difference on anything?
 
Hmmmm. That is bizarre.... are you certain you're plugging into the proper sockets? It's a real nuisance to identify the sockets, which is where the factory "mushroom" tool comes in handy (click here). I suspect it's more likely to be connected to the wrong pins (and/or with wrong wires) than to be a defective blinker box, they are quite simple internally... just an LED, diode, and button. It sounded like you had the correct socket numbers though, based on what you wrote in post #10.

BTW - is your "Check Engine" light on? And does it light up when you turn on the key, before starting the engine, indicating the bulb is good?

Your best bet for full diagnostics is the Chinese SDS, but that's about $500-$600 from Chinese sellers with minimal support, or ~$1k from a US-based seller with personal tech support (MackHack on the BW forum). Not cheap, but guaranteed to do everything possible on the 500E. There are some other scanners out there which will do maybe 60-80% of what the SDS can do (varies with brand/model) but they're still $300-$400. The $40 blinker is still the cheapest, and most of the time it works fine. Sure wish I knew why you are having so much trouble...!

:(
 
Thanks for info on testers!

I will upload an image of the wires when connected to the pins. But, is it possible the "brain" or something else is causing it to not throw codes?

I can't say I have the Check Engine light in the instrument cluster. I have ASR which is impossible to clear it seems. This is a Swiss Car, so there is no onboard "DM code reader push button".

Didn't think the 500E had the check engine light..?

I will check everything once more and upload that picture.

I just got an apptmnt with another specialist recommended by the first specialist (this must be a good thing). He has the Star. Its tomorrow at 1100 GMT. I'll post the results from this visit.
 
Ah, now I understand... you're across the pond, eh! Only US-spec cars have the Check Engine light and DM (Diagnostic Module), it's for emissions reasons - the CEL lights up when there's any fault which can affect emissions. Tip: You can update your profile to indicate your location, i.e. Germany, UK, Europe, etc.

The specialist with the Star diagnostics (SDS) should be able to provide you with a full list of all codes from all modules (ask for a printout), and clear all the codes as well. Problem is, you need to clear the codes, then drive the car a bit and see which ones return. Often there are a few "junk" codes which can send you on a wild goose chase. Codes which come back quickly (either immediately, or within 1 hour of driving or less, over several stops/starts) are the codes which require immediate attention.


:roadrunner:
 
Allright - profile updated :)

The specialist had the Star diagnostics, but he was not very familar with the 500E.

We took the Star for a readout, and it went through all the systems one by one. Since the readout was in German (not my native language), we had to translate "between the lines", and unfortunately mechanics today don't really have time for in-depth analysis in something they don't really understand..

But anyways, there was one fault stored. The screen said LH1: code 10.

Other than that the mechanic told me the air mass sensor was mentioned in a long sentence (in German!).
He also said there was a message regarding the drivetrain. I didn't know the drivetrain would throw anything..

Well, I don't know much more since he really didn't have time for us (me and the car), and kinda tried to turn away from the "job".
He was not able to print anything from the Star either - pointing at the printer that was not there.
Worst of all - he charged me $50!!

From the disappointment of politely over-paying for a 15 minute "job", I went next door to a well known transmission specialist (it's all he does), who actually did the overhaul a year and a half back or so.
I just ordered the Neutral Safety Switch a week ago, and he will install it for me, and also fix a gasket and drain plug leak, along with checking out if there are other bad things such as the overload protection switch. He told me that the vaccum hose I described to him, that had been discovered just hanging by the right side of the transmission some months ago, was nothing to be worried about. The hose is only there for emmission reasons he said. As mentioned earlier, the vacuum hose was closed by a mechanic, since there was nowhere to connect it!

- to sum up -
LH1 code 10 I assume is the contact idle switch right? If so is the case, I have had the same fault read in the past couple of star diagnoses I've had done the last year.
It has been clearable earlier, and also this time - which has me puzzled since the ASR light still is on, even if the code was cleared. ASR light seem to be unwavering!
Well, the mechanic who pulled the 10'er code, said that it could be the potentiometer on the idle switch, or a potentiometer inside the ETA going bad.

I don't know if the NSS would take away the ASR light - the transmission specialist sure didn't think it will. Maybe I'll need to get the contact idle switch behind the pedal next, so that may be ruled out also.

Do you have any other tips/ideas for me to pursue?
 
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I do however have (and had it before - maybe 6 months ago before it went away again) the SRS light showing up/going away on slow starts right after engine has been fired up. It is often a result of turning the wheel while driving slow. It goes away as soon as I pass something like 30 Km/h (20 mph) or so it seems.
 
Hmmm. From the link in post #7 above (see page 8 in the PDF file), LH code #10 in English is:

"CTP (idle) recognition from EA/CC/ISC control module (N4/1) or CC/ISC control 23 15.0
module (N4/3), short circuit"

Drivetrain message = codes from ABS/ASR module, and is likely to be the primary reason the ASR light is on. Bummer he didn't tell you the code for that one!

Intermittent SRS light is probably a contact ring issue, either worn brushes, dirty rings, or a bad solder joint at the contact ring. There are blink codes for the SRS system too, if you could get your blinker box working....

:seesaw:
 
I'm going to try my blink code reader again tomorrow morning. There must be something I'm not doing right.

I also didn't think it was the ICS but just as you say - the CTP - Idle recognition from EA/CC/ISC ... But I was being convinced by the guy who attached the Star, since I had the ICS pop the last time it was diagnosed.

So my question is then; is the drivetrain message a totally different issue than the pin#4 code 10 issue? If so, what is it that will cause the pin#4 code 10 being thrown?

Also, are Drivetrain messages related to a specific pin number? Could the transmission be a factor when coming to a drivetrain message?

Lastly, I remember months ago, when I actually could take the car for a ride, without having the ASR limp mode go off/being constantly on. When I tried to accellerate fast while in a turn, there would be an agressively loud grinding noise, coming from under the car - back-end of transmission/drivetrain/rear axle area. It sounded like a heavy duty drill going through concrete. Of couse I almost shit in my pants, but I've been silently neglecting it, and instead taken it easy on the throttle since then. My first pri has been to figure out the ASR issue, but maybe I should've payed more attention to the origin of the grinding noise.

Does any of this give you any new clues?

Maybe you have/know of a link to a document describing the drivetrain and its impact, and which is focusing on the w124/500 systems..?
 
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So my question is then; is the drivetrain message a totally different issue than the pin#4 code 10 issue?
Most likely they are totally different, but the code from ABS/ASR will confirm this.


If so, what is it that will cause the pin#4 code 10 being thrown?
See my previous post - sounds like a wiring issue (short circuit), possibly related to the ETA. How old is the ETA?


Also, are Drivetrain messages related to a specific pin number?
Yes, ABS/ASR is pin #6 on the diagnostic port.


Could the transmission be a factor when coming to a drivetrain message?
Internally no. But the neutral safety switch (aka starter lockout switch, gear position switch) can affect this. If this switch is original, it's suspect. Details here.


Lastly, I remember months ago, when I actually could take the car for a ride, without having the ASR limp mode go off/being constantly on. When I tried to accellerate fast while in a turn, there would be an agressively loud grinding noise, coming from under the car - back-end of transmission/drivetrain/rear axle area. It sounded like a heavy duty drill going through concrete. Of couse I almost shit in my pants, but I've been silently neglecting it, and instead taken it easy on the throttle since then. My first pri has been to figure out the ASR issue, but maybe I should've payed more attention to the origin of the grinding noise.
That doesn't sound good, but I don't have any clue what it might be. I'd see if you can duplicate the noise again.

:detective:
 
One more thing I remember after digging earlier today:

When I did the battery-cable-off trick, to see if it would reset anything, I blew the fuse which goes to the radio, roof light, ++. After reading this thread from another site - http://home.mxboy.com/viewthread.php?tid=41004 - I wonder if a fuse for the base module could be keeping me from getting any readouts..?

Is there one/more fuses inside the box where the base module sits? There should be several modules sitting side-by-side in there right?

From what the guy describes in the link about the blink code reader giving a weak signal, it sounds very close to what I've experienced.

- to answer your questions -
Yes the ETA is more than likely factory installed. In fact the wiring was "fixed" right before I bought the car, but to our (the first specialist) amazement the wiring had been surrounded by electrical tape, and that sounds fishy! By the way the specialist I'm referring to is actually a well known electrical fault diagnose specialist, who only works on MB's, and he goes by his firstname accross the country. He didn't think it would be the ETA being the culprit, but was never able to check throughly due to his faulty Star diagnose battery. That's why I haven't been over-eager about mentioning thos part. Also, I read that most often the ETA is not the culprit, and many people have ended up wasting money on this thing.

It will be nice to finally replace the NSS, to really see if it will fix it. Shouldn't it really throw codes though?

About the grinding noise - I did get this sound a couple of times actually. It is definitely not just a bypassing thing. It has the characteristics in its sound as if something is slipping teeth; meaning it is affected by the amount of force, from the combination of the turn and the boost from the accelleration, which causes an "uneven" grinding sound depending on the total force being applied. Not easy to describe sorry.
 
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Allright, thanks Gerry.

So, I did a new attempt diagnosing with the blink code reader today.

No luck. See video for my attempt on diagnosing one of the pins (LH pin# 4 in this cut). - http://www.youtube.com/watch?v=AxpxJpXEnMc&feature=mfu_in_order&list=UL

I also convinced myself of opening up the "computer box". (See picture). I found:
011 545 97 32 (Base Module) - original part#
013 545 36 32 (ASR Module) - Bosch part - original part#
124 545 44 32 (E-GAS Module) - original part#
015 545 36 32 (LH Module) - NOT original part# - should've been 016 545 14 32 (As of indent. no. B840527)
*Referencing EPC 2008.01

My immediate question: Is the 015 545 36 22 (LH Module) an earlier or later part - meaning am I running an older version than B840527? Mine is later (B9209xx). I've heard the '92 LH modules are more powerful.. but are they a match?

I checked the 4 fuses in the box (BM), and they seemed OK. (don't mind the one missing in the picture).
What I discovered was the signature sitting on the ASR module. That is the signature of my fellow "well known MB specialist" I mentioned a few times earlier. It seems if the part# is correct, so I guess he didn't swap it or anything - probably just checked it while I had it in for a harness rewire. I'll check with him.

Is it correct that the LH module may be a problem part?
 

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My immediate question: Is the 015 545 36 22 (LH Module) an earlier or later part - meaning am I running an older version than B840527? Mine is later (B9209xx). I've heard the '92 LH modules are more powerful.. but are they a match?
The 015-545-36-22 LH module is correct for a 1993 500E and is likely the factory original module. Remember, the EPC does not always list the complete supercession chain, i.e. every part that was ever used during production. Some times the EPC only lists the current replacement module, and that is the case with the LH module - this is why you are seeing 016-545-14-32 in the EPC. The 1992 LH module is worth a power gain if you're interested in that as an upgrade, but that's a different discussion.


Is it correct that the LH module may be a problem part?
Nope, that's not a problem. At least, it's extremely unlikely to be the cause of your ASR light on and limp-home-mode issues. The LH basically controls just the fuel mixture. The E-GAS module controls the ETA.
 
That's good news about the LH module not likely causing this. Maye I'll look into a replacement chip and/or a '92 LH module when I'm getting all the trouble away. There must be other reasons why they only have the superseeding LH part in their lists I guess.

No luck. See video for my attempt on diagnosing one of the pins (LH pin# 4 in this cut). - http://www.youtube.com/watch?v=AxpxJ..._order&list=UL
By the way, before I did as seen in that video, I got a constant red signal from the blink code reader. But that was before I put the key in the ignition. I got the red signal right after I hooked up to the pins - with ignition off ..

Didn't know the pins should give any signals before one applies power to the system.. Could there be a ground problem somewhere?

I'm going to find someone who will put the Star diagnose in action for me, since I feel a bit obnoxious going back to the guy who charged me $50 the last time.
It will take some time, but I hope to find someone to help me this week. And this time I'll grab with me a German dictionary!
 
Today I went to a third indy shop, who often works on 80's and 90's MB. They had the Star diagnose compact4 system.

Surprisingly enough, they were not able to diagnose any port whatsoever (38-pin socket). Reason; no response from neither EZ1, DM, EFP, TPM, GM, ASR, ABS, nor ATA (I only knnow what half those are - feel free to enlighten me).

As I mentioned in above post, I was not able to manually diagnose with the blink code reader earlier this week myself.

So the big question is: why would a top notch, MB original, Star diagnose apparatus not manage to read any data from the 38-pin connection? There was no connection to the individual ports/pins.
Or let me rephrase: WTF is going on?!

My first suspicion is of course that there is a ground problem, hence that there is no power going to the modules, giving the Star nothing to work on. The car starts, runs (in ASR fault mode), has all conventional electrical working except the alarm (as far as I can remember), and doesn't stop until I turn ignition off.

See my picture of the Star diagnose results.

Any other theories folks?




(I was told the exclamation marks on the screen (see picture), means there is no signal/connection to the respective module)
 

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Something is definitely fishy. I suspect either a problem with your 38-pin connector socket(s), or your indy's SDS (Compact 4) unit. Only way to prove his SDS is working properly is to get it communicating with another car with M119.97x engine (LH injection). I'm suspicious of the Compact4's "no communication" fault when the previous indy was able to successfully pull codes. The plot thickens, eh?

:stickpoke: :detective:
 
Is the small wire connected at the positive terminal of your battery in the trunk with no corrosion, etc.? This small diameter positive wire provides power to all of the computers DIRECTLY off of the battery. It was the cause of an intermittent inter-computer communication problem on my car; tightening up the connection solved the problem. The large positive battery cable provides power to the rest of the car's systems, but the computers get their own lead right off of the battery. Something to check out.

Cheers,
Gerry
 
The plot thickens, eh?
Yes, getting really frustrating - but interesting :-)

Is the small wire connected at the positive terminal of your battery in the trunk with no corrosion, etc.? This small diameter positive wire provides power to all of the computers DIRECTLY off of the battery. It was the cause of an intermittent inter-computer communication problem on my car; tightening up the connection solved the problem. The large positive battery cable provides power to the rest of the car's systems, but the computers get their own lead right off of the battery. Something to check out.

Cheers,
Gerry
Definitely something to check out gerry. I had the battery cable come off while I tried to reset earlier, though this was before the previous star diagnose, in which case it had contact (different Star).

The battery cable for the positive connection in the trunk, is very much corroded yes.

I didn't pay attention or notice the small wire, but I remeber reading something about this a while ago.



Thanks, I'll check in the morning. Is it pretty obvious where the small wire is sitting, when looking at the battery in the trunk?
 
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Hi again my 500 folks, some new updates on the situation..
Please help me understand what is going on..

- Earlier posts -

ASR light constantly on since summer. Cannot clear the ASR light. Not by restarting engine, unplugging battery +12, resetting faults with flash code reader, BasicDiagnosis SD-102, Star Diagnosis SDS Compact3, nor with SDS Compact4.
Last post: The car was in for fault reading using Compact4 – every module reading failed


Here is what has happened since then (last 10 days or so):

- In chronological order -

• The transmission has been leaking appx 1 liter fluid the last year
• Transmission guy replaces the trans oil pan + drain plug gaskets – fills up
• He also tries to replace my newly bought neutral safety switch (NSS), but needs to demount whole transmission
• So the NSS was not replaced
• When I picked up the car, I talk to a second mechanic. We setup an appointment to do a diagnose on his HHT (original MB).
• I drive the car again – still ASR lamp all the way
• I drive quite a bit and feel the engine has quit missing – the puffs in the exhast – probably placebo
• Car still sounds like it runs on 7 cylinders
• A couple of days later, I meet up to my appointment
• He reads several faults with his HHT

- Current stored faults -

ASR: code 030 – CAN: No reception from EFP N4/1
EFP: code 009 – Control module EFP N4/1
EFP code 014 – Control module EFP N4/1
EFP code 051 – Idle speed safety contact M16/1s2

- Random faults -

Starter lock-out/backup lamp switch (didn't get a picture)
(Note: not sure if this was the (S16/1) or the (S16/3) (transmission range recognition) – or even if it matters..)

- As continued -

• He clears the codes
• As I try to interpret the codes by using this cheat sheet http://www.w-124.info/w124/DTC_List_W124_M119.pdf, I find the code 009 maybe being the ”Intake air temperature sensor, open/short circuit”
• I remember a year ago, when I got a fault on the cable/switch sitting in the left head lamp, which I think has to do with the outside temp measuring for the intake or something..
• So I touch the cable, and it is almost falling out (very loose but sits)
• I don’t think anything more about it until now, because:

- Yesterday –

The car started without the ASR lamp being lit!!! I step on the pedal to my amazement, and the car ”comes to life” :) (I’d totally forgot how it once felt like).

- Today –

Today I have started the car 7 times – NO ASR LIGHT!


So please help me, because I’m really struggling to see why the f** it suddenly runs clear of that damn lamp.

I have 3 theories. 1. The outside temp measurment being ok after I touched it. 2. The transmission guy fiddling a bit with the NSS. 3. The second guy cleared the codes successfully (but not the ASR lamp).
For that number 3 – I read somewhere that some type of faults don’t show until it has been counted x number of times – and also doesn’t clear until counting back to zero..

Anyone got some clever ideas??
What are the actual codes - as I had some trouble interpreting EFP and maybe also the ASR faults?
 

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You said the positive battery terminal cable(s) were corroded. Did you clean the positive battery cable terminals with a wire brush, sandpaper or something? Remember that this one, small cable attached to the positive terminal is the only thing that supplies ALL power to the entire CAN box computers.

A couple of the codes you show are common and should pretty much be ignored - the idle speed safety contact and backup/stop lamp switch codes are common and shouldn't have any affect on your ASR issue. I have had these codes on my car for years (as have many others) and they don't affect the running of the car.

The three codes pertaining to the N4/1 module and the CAN are what intrigue me. These are similar to the codes I was seeing with my small battery terminal cable not supplying power to the the CAN computers on a constant basis. The connection between the computers on the CAN was being momentarily interrupted because of the poor electical connection at the positive (+) battery terminal supplying power to them. Once this was cleaned/firmly connected, I've had no problem and the car is running 100%.

You mentioned that your + terminal cable ends are badly corroded, yet you didn't mention that you'd fixed this. Ensuring proper and consistent electrical power to the computers should be a baseline condition to any further diagnosis you do. I had to deduce this based on WIS diagnosis flowcharts.

Let us know what you find and take some photos of your battery terminals.

Cheers,
Gerry
 
Thanks Gerry, I will post a photo.

I never did anything to the positive terminal, so it is still corroded. But of course humidity and cold wheather could have affected the connectivity.

I didn't clean them because The rest of both cables going from the +12 terminal seemed corroded, and I assumed it would be bad all the way up.

I will try cleaning the end points of the cables and the terminal tomorrow. I'll also do the same with the ground.

Any thoughts on the cable and switch going to the left headlight?
 
Any thoughts on the cable and switch going to the left headlight?

-To be a bit more precise - I'm talking about a temp sensor at the tip of driver side intake, that measures the air temp going into the engine, and adjusts the timing for best efficiency.

Is it possible for it to cause misfiring and an ASR light?

See my attached video - it shows very low rpms, and some ups and downs on the odometer, when shifting to D and back to P, and then I barely give it a bit of throttle - which makes it surge almost dying.

Does this seem to be related to the misfire and the ASR light somehow?

http://youtu.be/Boisw57Le84
 
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-To be a bit more precise - I'm talking about a temp sensor at the tip of driver side intake, that measures the air temp going into the engine, and adjusts the timing for best efficiency.

Is it possible for it to cause misfiring and an ASR light?
No. The intake air temp (IAT) sensor has very little effect on engine operation and it would not cause misfiring, ASR light, or limp home mode.

:o
 
Let us know what you find and take some photos of your battery terminals.

Cheers,
Gerry
Here is a picture of the corroded +12 V cables going from the battery+ terminal.

I've cleaned them up with electrical spray, followed by anti corrosion spray. They looked better after that
 

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Today I was back to ASR hell.

The last 4 days I've been able to start the car 10-12 times, drive a full 30 minute journey, with a fully functioning car.

But then today, this happened:


• I start the car, drive from work, and after 10 mins (while driving) the ASR light pops

• Idle has been low the past 4 days - see video above (about 450 rpms at idle) - http://www.500eboard.com/forums/sho...-Switch-an-issue&p=16511&viewfull=1#post16511

• I tried to restart the engine, and this time that actually cleared the ASR light (has not been possible for several months)

• The car seems a hell of a lot more powerfull and responsive now -the idle is sitting perfectly at 650 rpms this time! - see new video in the link below.

• This time it requires very little push on the pedal, for the car to take off - nice but maybe a little too much.

• I drive another 5 minutes, and the ASR light lits up again. - it almost seems if it happens when either letting go of pedal, or when giving very little throttle

• The rpms go back to low 450's, and the throttle is not as responsive and juicy again

• I clear it again and drive.

• It feels as if something responsible for idle/conpensation is "driving" the car - almost as if the cruise control is set. The engine speed doesn't slow in particular, when letting go of pedal or even when driving downhill.

• And further, the ASR mode happens once more on my 30 minute drive


Hope my attempt to describe is helping :-)


http://youtu.be/ouRmmFN_L3o
 
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WAIT. I just saw this:

He also tries to replace my newly bought neutral safety switch (NSS), but needs to demount whole transmission

That is NOT TRUE. The switch can be replaced with the transmission in the car, you don't even need to loosen the mounts and push it to one side. Space is very tight, but you CAN replace the switch. I've done this on both my 500's. Takes less than one hour. If you still have the old switch in there... you MUST REPLACE IT if the error code keeps appearing on the E-GAS module.

Also, your screen shot shows there are more than 3 error codes for "EFP", there is an arrow to a second screen! Your tech goofed up and didn't give you the other codes!!!

:(
 
Yes, I really wish he could have bothered replacing it, despite the tight space. Now I have to start looking around for someone else to do it, since I don't have the equipment or the lift to do the job.

About the EFP page 2/2.. I'm pretty sure that was the Starter lock-out/backup lamp switch - temporary fault that I didn't get a chance to document.

I've been thinking; there must be a problem with a temporary fault, which is counted and stored as a permanent fault (hence ASR light), when reaching a certain limit. I bet all the other shops who have diagnosed it, while the ASR light was impossible to clear out, never actually cleared the stored permanent faults. Either because the equipment was wrong, or because they didn't know how to use it. Here in Norway most shops don't own a SDS - they rent it from the dealer.

Could this be a returning constant ASR light, which won't clear when restarting the engine? That it will be stored permanently again? In if the case, will it narrow the possible culprits?
 
The Starter lock-out/backup lamp switch & neutral safety switch (NSS) are the same item.

You can & should do the NSS replacement job yourself. A Search will show several threads which describe the procedure. The procedure is also provided in the FSM.

At the very least, provide this information to your mechanic, because if the mechanic is telling you that the transmission must be dropped to enable switch replacement, the mechanic does not know enough about these cars.
 
At the very least, provide this information to your mechanic, because if the mechanic is telling you that the transmission must be dropped to enable switch replacement, the mechanic does not know enough about these cars.
I actually told him in advance, so he probably had too little time available (he was replacing other stuff as well), and thus gave me his most convinient answer afterwords.

But if this is a job any mechanics could do (with some guidance from here), I have a couple of others at hand who I trust. But I wanted to let the Mercedes only, taxis #1 man, 20 years of experience specializing in transmission only mechanic make an attempt at it. He often's got Brabuses from the 90's, 500 and 600 MB's, and other exclusive cars in his shop from time to time. So I was a bit surprised about his inability.

Do you have a well described, picture rich guide for the NSS replacement? I will look into it myself maybe.
 
So, today I went back to diagnose the merc at the same place as last week.

I haven't been bothered more than 4 times, regarding the ASR light since then.
I've tried to clean the battery terminals and the cables as Gerry suggested.
I've tried to flash code read the diagnostics 38-pin - no luck on getting any response this time either.

This time the following faults came up using the same HHT from MB:

ASR: code 030 – CAN: No reception from EFP N4/1
EFP: code 009 – Control module EFP N4/1
EFP code 014 – Control module EFP N4/1
EFP code 051 – Idle speed safety contact M16/1s2
EFP code 224 - Idle speed contact switch S29/3

NOTE: see the rest of this same diagnosis in the next post!

Gerry: These faults were probably thrown BEFORE I cleaned the battery terminals/cables - because I haven't seen the ASR light after I did the cleaning..
 

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..continued from last post.

Next thing we did was:

1. Started the fault erasing procedure
2. Got a message (see picture) saying "EZ1 - Fault memory has not been erased"
- The problem was the diagnosis cable, which we adjusted
3. Restarted the process again (see picture of short test)
4. Received one fault that obviously couldn't be erased - the "EFP code 224 - Idle speed contact switch S29/3"
 

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Yesterday I recorded a video showing the ASR light switching on while engine at idle.

I've noticed the cold start function is not working as it should either - many times the needle goes right down to normal idle speed right after I start the engine in the morning, even when it is below 30F outside.
The cold start function should keep it running at 900-1000 rpms for 20 seconds right?

While driving (ASR light off) something is pushing more gasoline/air?.. into the system, and it is the same feeling as when cruise control is on, and I kind of have to brake to slow the car down. Sometimes I can see the needle jiggling when letting go of the gas pedal. It's as if something is turning on/off or not keeping back gas/air.

It doesn't strike me as being a vacuum leak, since I guess a vacuum leak would give constant high rpms.. And that's not the case, because normally at idle, I would have 450-500 rpms as described earlier.

The ASR light doesn't seem to come on unless decelerating/at idle (never at hard throttle), and looks like the ECU is detecting too high throttle or something - opposite of what is intended by the driver.

Note: In this video I am not doing anything other than switching the ignition on and starting the car. I'm not touching the gas pedal at all..


VIDEO - ASR LAMP LIGHTS UP:
http://youtu.be/2GoUHDZho5o


Could a fuel pressure regulator be doing this? ..purge valve? fuel evaporation?
I guess the overload protection switch would't be able to cause the situation in the video..
 
Anyone got any ideas?

Please watch the video. Does it reveal a familiar pattern?

Pretty much the idle goes up for no reason, and then probably the ECU gets a mismatch signal between the idle contact switch and the throttle potentiometer readings..?

Something is not adjusting idle stabilization correctly or simply giving bursts of throttle due to an electrical issue. My upper wiring harness is brand new
 
Anyone got any ideas? Please watch the video. Does it reveal a familiar pattern? Pretty much the idle goes up for no reason, and then probably the ECU gets a mismatch signal between the idle contact switch and the throttle potentiometer readings..? Something is not adjusting idle stabilization correctly or simply giving bursts of throttle due to an electrical issue. My upper wiring harness is brand new.
I'm really suspicious of your ETA, especially since you said it's probably original.


Could a fuel pressure regulator be doing this? ..purge valve? fuel evaporation?
No, no, and no.


I guess the overload protection switch would't be able to cause the situation in the video.
Correct. You either have a bad ETA, or a faulty signal to the ETA (switch on the trans, etc).


:(
 
I'm really suspicious of your ETA, especially since you said it's probably original.

Correct. You either have a bad ETA, or a faulty signal to the ETA (switch on the trans, etc).
:(

Yes, your suspision seems reasonable. I've started to believe the ETA actually could be the culprit after all. One reads it's often not the cause, after replacing it. But taking into consideration the wiring of that ETA has been "fixed" two years ago (which I have no information on except the black electrical tape surrounding the whole harness, and that I've gotten it confirmed by previous owner). And also the very uneven throttle, lack of power on low rpms at times, and the cut off at 4000 rpms, it reminds me more and more of a broken/intermittent electrical current in those wires.

The throttle actuator is only $800 and it comes with 5 year warranty here in Norway.

Besides the NSS will throw codes..

Any final suggestions on other switch that I can check, before I potentially waste a buck or two on a brand new ETA?
 

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