What is the difference between these numbers and colors?

[m119ahmed]

Hello
I'm happy to join the forum.

I'm not sure if my question is in the right place, as I'm new to the forum and this is my first post.

I was wondering if the stickers on the engine control unit have any meaning based on their color, or if they're just stickers with no significance. Some units have the same number but different label colors.

My second question is some are numbered, for example 0007 others 0014, and some have no number. Do these numbers represent a specific difference within the control operation?

I hope my question is clear. I've attached some pictures to illustrate what I mean.
Please excuse me if my question has been asked before.

 

[gsxr]

AFAIK the dots have no sigificant meaning, or at least I can't figure out why the colors vary. And, some modules have no dot at all.

The LHxxxx number appears to be related to the age/revision of the module, but again, it doesn't appear to indicate anything that you can't tell from the part number of the module.

Welcome to the forum!

 

[R129 UK]

AFAIK the dots have no sigificant meaning, or at least I can't figure out why the colors vary. And, some modules have no dot at all.

The LHxxxx number appears to be related to the age/revision of the module, but again, it doesn't appear to indicate anything that you can't tell from the part number of the module.

Welcome to the forum!

Those stickers are usually for internal QC purposes such as identifying an operator / production line or to indicate a test stage has passed etc.

 

[036]

Welcome here! I love nerds.

 

[m119ahmed]

Thank you for your replies.

Actually, the reason for my second question is that a friend of mine says that Lh numbers 0010 and below have no speed limiter, while numbers 0011 and above all have a speed limiter. I haven't tested this myself yet, but I have some friends, some with W140s and others with W124s, who don't have the same speed limiter on the same number, let's say 0014, for example.

Another note
My 400e is imported from Japan and comes with a control unit (015.545.34.32) without the LH number, and a transmission (722370) taken from a 500SEL. While testing the control units with the number 00xx, I noticed that the transmission engages from first gear, unlike the other units without numbers, which engage from second gear. Note that these do not have an S/E switch. I don't know why!

 

[gsxr]

Actually, the reason for my second question is that a friend of mine says that Lh numbers 0010 and below have no speed limiter, while numbers 0011 and above all have a speed limiter. I haven't tested this myself yet, but I have some friends, some with W140s and others with W124s, who don't have the same speed limiter on the same number, let's say 0014, for example.

AFAIK the "LH00xx" number has nothing to do with the presence of a speed limiter. That is a function of the module part number. Anyone who claims their car doesn't have a limiter... first you need to know if their LH module has a stock EPROM/chip, and second you need to know how exactly the person verified their car wasn't limited. Not many 124's or 140's can exceed 155mph / 250kph to prove this. All that's needed to remove the limiter is a performance EPROM like this one.

My 400e is imported from Japan and comes with a control unit (015.545.34.32) without the LH number, and a transmission (722370) taken from a 500SEL. While testing the control units with the number 00xx, I noticed that the transmission engages from first gear, unlike the other units without numbers, which engage from second gear. Note that these do not have an S/E switch. I don't know why!

All USA and Japan-spec 400E's have 2.24 rear axles and all of those start in 1st gear. This has NOTHING to do with the LH module, it's a function of the valvebody in the transmission. Since your transmission is from a 500SEL, most likely the original 400E valvebody was swapped into the 722.370 transmission you have now. You'd need to drop the pan and read the numbers on the valvebody to confirm this. It's also possible to have an electronic first-gear start added though, so if the valvebody is the 722.370 second-gear-start, then it must have electronic FGS.

All USA and Japan-spec 400E/500E lack the E/S switch as well.

 

[m119ahmed]

AFAIK the "LH00xx" number has nothing to do with the presence of a speed limiter. That is a function of the module part number. Anyone who claims their car doesn't have a limiter... first you need to know if their LH module has a stock EPROM/chip, and second you need to know how exactly the person verified their car wasn't limited. Not many 124's or 140's can exceed 155mph / 250kph to prove this. All that's needed to remove the limiter is a performance EPROM like this one.

Okay, I understand you. Do you have a 4.2 chip?

All USA and Japan-spec 400E's have 2.24 rear axles and all of those start in 1st gear. This has NOTHING to do with the LH module, it's a function of the valvebody in the transmission. Since your transmission is from a 500SEL, most likely the original 400E valvebody was swapped into the 722.370 transmission you have now. You'd need to drop the pan and read the numbers on the valvebody to confirm this. It's also possible to have an electronic first-gear start added though, so if the valvebody is the 722.370 second-gear-start, then it must have electronic FGS

I didn't replace the valve body. I bought the car without a transmission and later bought a used one and installed it as is.
next time I change the oil, I'll check the part number to see if it has been replaced before

 

[gsxr]

Okay, I understand you. Do you have a 4.2 chip?

Not officially... there's been almost no demand. I could make one, but I'd need to know the part number of the current LH module.

 

[m119ahmed]

Not officially... there's been almost no demand. I could make one, but I'd need to know the part number of the current LH module.

Lh ( 015 545 34 32 )
chip ( 2 287 357 919 )

 

[m119ahmed]

electronic FGS.

Do you mean this one? Yes, my car has it.

 

[gsxr]

Lh ( 015 545 34 32 )
chip ( 2 287 357 919 )

Got it. I'd need to test my custom chip in that particular module to verify it works as expected.

Do you mean this one? Yes, my car has it.

No, that is a diode for the power seats.

The electronic FGS modules are either aftermarket (adjustable / programmable from BergWerks or FGSSwitch), or a modified OE FGS relay from the 126 chassis (fixed function, not adjustable). All of these work by monitoring the speed signal (yellow/green wire behind the cluster) and then energizing the kickdown solenoid at low speeds or when stopped, simulating the shift lever in "B" position to trigger starting in 1st gear. The solenoid is de-energized to allow shifting to 2nd gear when the car is above a certain speed, then the shift point varies based on throttle position (Bowden cable).