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OWNER asultan

So before testing in the car. Continuity was checked in a number of places before any soldering occurred, again namely pins 2 and 7. They were continuous— so then I began by again.. removing old FRAKO capacitors for new 220mf 50V units, making sure to observe their respective polarities (+/-).

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new caps:

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Found this original builders note tucked in the ECM.

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Plugged into the car, no initial butt dyno or ear dyno differences yet..
 
Longtime gone but im still here, car has been running smoothly since last years overhaul and now its at my mechanic for freon to charge up the A/C system that I fully refurbished last summer----that resulted in a myriad of other mishaps----that resulted in the engine overhaul lol.

My mechanic is running into a problem though. I installed a Denso 471-1230 (94/6?-99) S320 AC compressor which uses Sender Unit P/N: 0001500625.

My mechanic initially told me that I was leaking freon through my BRAND NEW nissens condenser, so that went straight in the trash, and a new Genuine MB condenser was purchased and sent to them. But now theyre having trouble with this A/C Compressor Sender unit. Its a new compressor with no miles on it so I don't know whats going on.

The other issue is this sender unit is on backorder with no dealerships in the US stocking it, as well as no ebay sellers selling them... looking for some advice.

pics for attn

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Eh... what "trouble" are they having with the new compressor speed sending unit? It's extremely unlikely to be defective new out of the box.

What problem is this causing?

:blink:
 
gsxr said:
Eh... what "trouble" are they having with the new compressor speed sending unit? It's extremely unlikely to be defective new out of the box.

What problem is this causing?
Click to expand...
@gsxr Im quite honestly not sure. They just said its.. not working as it should be to engage the clutch? Im actually not fully sure what signal its sending, where the signal its coming from, and if the signal im assuming is for the clutch only?
 
asultan said:
@gsxr Im quite honestly not sure. They just said its.. not working as it should be to engage the clutch? Im actually not fully sure what signal its sending, where the signal its coming from, and if the signal im assuming is for the clutch only?
Click to expand...
I believe the compressor RPM signal is only used to compare to engine RPM, so the HVAC system (the KLIMA relay, I think, on a 300E) will disengage the compressor if the RPM's don't match. Now, since your compressor isn't the original application, I don't know if the signal is the same as the original 300E compressor.

Had the new compressor ever been working normally since installation? If so, great, the S320 compressor is not a concern.

Are you confident in the technical abilities of this particular shop?

Backing up a bit... what is the root problem here? Does the AC not work at all, i.e. the compressor won't engage? Or, engages for a couple of seconds then the compressor shuts off?

:scratchchin:
 
gsxr said:
I believe the compressor RPM signal is only used to compare to engine RPM, so the HVAC system (the KLIMA relay, I think, on a 300E) will disengage the compressor if the RPM's don't match. Now, since your compressor isn't the original application, I don't know if the signal is the same as the original 300E compressor.

Had the new compressor ever been working normally since installation? If so, great, the S320 compressor is not a concern.

Are you confident in the technical abilities of this particular shop?

Backing up a bit... what is the root problem here? Does the AC not work at all, i.e. the compressor won't engage? Or, engages for a couple of seconds then the compressor shuts off?

:scratchchin:
Click to expand...
The aux fan won’t come on and the compressor won’t cycle apparently… they relayed the rpm switch but the pressure switches are just not having fun… but i think they’re going to add relays there as well? it’s because it was a shoddy 134 conversion apparently from the previous owner. all i did was just replace existing components with their counterparts. I do trust them though they are a very competent shop, just…. really really slow.
 
The pressure switches are separate / isolated circuits. The aux fan will turn on at 16 bar (230 psi) but ONLY if you have the new style Red switch. If your car still has the original Green switch... ugh... that one doesn't turn on until 20 bar (290psi) which means the aux fan almost never runs.

I'd want to know more about "the compressor won't cycle". The compressor normally runs continuously, until the evaporator temp sensor reads low enough to turn the compressor off for a short period, then it turns back on. If vent temps are poor (due to a lousy conversion) the temps may never get low enough to cycle the compressor. Ditto if it's really hot out, and/or if the main air flap vacuum pods are bad so there's no 100% recirculation function either. If the compressor won't turn on, that's a different discussion.

AFAIK the only way the compressor RPM sensor would potentially cause a problem is if the compressor engages for a few seconds and then shuts off, and won't turn back on until you cycle the ignition.

Sounds like you need to axe the shop more questions!

:duck:
 
gsxr said:
The pressure switches are separate / isolated circuits. The aux fan will turn on at 16 bar (230 psi) but ONLY if you have the new style Red switch. If your car still has the original Green switch... ugh... that one doesn't turn on until 20 bar (290psi) which means the aux fan almost never runs.

I'd want to know more about "the compressor won't cycle". The compressor normally runs continuously, until the evaporator temp sensor reads low enough to turn the compressor off for a short period, then it turns back on. If vent temps are poor (due to a lousy conversion) the temps may never get low enough to cycle the compressor. Ditto if it's really hot out, and/or if the main air flap vacuum pods are bad so there's no 100% recirculation function either. If the compressor won't turn on, that's a different discussion.

AFAIK the only way the compressor RPM sensor would potentially cause a problem is if the compressor engages for a few seconds and then shuts off, and won't turn back on until you cycle the ignition.

Sounds like you need to axe the shop more questions!

:duck:
Click to expand...
@gsxr THANK YOU! This is all of the information I needed, will relay this to them.
 
gsxr said:
The pressure switches are separate / isolated circuits. The aux fan will turn on at 16 bar (230 psi) but ONLY if you have the new style Red switch. If your car still has the original Green switch... ugh... that one doesn't turn on until 20 bar (290psi) which means the aux fan almost never runs.

I'd want to know more about "the compressor won't cycle". The compressor normally runs continuously, until the evaporator temp sensor reads low enough to turn the compressor off for a short period, then it turns back on. If vent temps are poor (due to a lousy conversion) the temps may never get low enough to cycle the compressor. Ditto if it's really hot out, and/or if the main air flap vacuum pods are bad so there's no 100% recirculation function either. If the compressor won't turn on, that's a different discussion.

AFAIK the only way the compressor RPM sensor would potentially cause a problem is if the compressor engages for a few seconds and then shuts off, and won't turn back on until you cycle the ignition.

Sounds like you need to axe the shop more questions!

:duck:
Click to expand...
@gsxr So it is the rpm sensor as you intuitively guessed. They think it’s because I installed Denso P/N 470-1230 (the W140 S320 compressor) (which I installed due to my auto belt tensioner conversion rather than the rubber version). Is there anyway to spoof this rpm sensor?

EDIT: Attached this pdf about using two Ice Cube relays? Found on THIS thread (see post #19)
 

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asultan said:
@gsxr So it is the rpm sensor as you intuitively guessed. They think it’s because I installed Denso P/N 470-1230 (the W140 S320 compressor) (which I installed due to my auto belt tensioner conversion rather than the rubber version). Is there anyway to spoof this rpm sensor?

EDIT: Attached this pdf about using two Ice Cube relays? Found on THIS thread post #19
Click to expand...
I'm not aware of any way to spoof the sensor. However, the thread linked above is interesting... appears that might be a way to bypass the sensor? You lose the belt protection function, but otherwise doesn't seem to have any other drawbacks.

:klink:
 
gsxr said:
I'm not aware of any way to spoof the sensor. However, the thread linked above is interesting... appears that might be a way to bypass the sensor? You lose the belt protection function, but otherwise doesn't seem to have any other drawbacks.
Click to expand...
Once again we figure it out before the shop lol
 
Serendipitous indeed. I’ve never seen another 500E out & about yet. However one E60 at a regional consigners, and only two 400Es. One parked on the main street of my home town & one I disassembled at a regional pick n pull.
 
All is well here, just been driving the car on short trips around town and going upstate a few times.

About to run a little summer oil change using some 229.1 spec 15W-40.

My left side parking light selection on the headlight switch now makes the interior lights, and buzzer turn on (as if i had left the key in ignition.)

First thought was to look at the N7 Relay as I’ve had intermittent bulb failure module flash occasionally with no loose, burnt, or missing exterior lamps/bulbs.

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Found a cracked solder joint and some corrosion.

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Didn’t seem to solve my problem though, if anything it made it worse. Time to get digging…

I also think my car needs a new chassis to bell housing ground strap as my dome light flashes with hazards on while the car runs.

I’d be more fine with it if it only happened with the car off but alas.

Other than that as a big brain thought I think i’m reaching the end with this car, kinda just tired of sundry creaks, old paneling, slow(ish) windows etc.

I still love driving it and how tight I was able to dial this car in, it feels so so good to drive how it sits.

A little torn clearly but nothing happening soon unless someone really offers me something for it.
 
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Didn’t get any further with the electrical gremlins.. also my drivers seat back position “peg” snapped off while I was making a mid drive adjustment—

BUT I did get my yearly 4 hour ish detailing session in and really conditioned the exterior to the best of my ability.

Interior and exterior glass blading with soapy water.
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Some toothpick work to get gross build up out of edges.

Some Gummi Phleging (still smells great)
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Clay bar, light polish, and a G Techniq EXO v5 coating for all external surfaces.

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