Hello, I'm brand new to this site and somewhat new to the car. I understand that the ASR and ABS lights come on commonly with the 92 through maybe 96 500sl's due to a short in the insulation of the wiring harness from the Electronic Throttle Actuator to some module (passenger's side firewall?). The previous owner said the fault code was the (ETA). I guess the insulation was biodegradeable?? Anyway, about 72k miles on this car, perfect show condition otherwise, garage'd, etc. etc. Scottsdale car, no rust, perfect visual condition...not trying to bragg, just giving information for someone who might have had this problem before.
Can anyone please show pictures of the wiring harness that fails, or possibly direct me to a link, etc.

Thanks in advance,

Jeff

JReed@veronicahome.com

480-270-0370

 

Go to any wire loom in the engine in bay and peel the outside covering off the bundle. If your loom is shot, you'll see it right away.

You don't need guidance once you see exposed wires and cracked insulation.

Good Luck!

 

I can't find any pictures of the engine bay to orient myself. I don't even know where the ETA's are (are there two??)? Anyway, I know there is an area in front of the passenger side firewall that has several electronic modules. I have the Mercedes 129 wiring CD with the Star Finder program, but I still can't figure it out...(pictures don't seem to match??).
If this is a common problem, I would hope there would be some links to some pictures, etc. I can check the general condition of other wiring harnesses, and possibly "luck" onto the one in question. But, I would still need as least to identify the ETA-to-"module" wiring harness before I start restoring the wiring. If I can identify the likely culprit, I can probably handle it from there.

Thanks again for the response,

Jeff

 

Jeff

If any of the wiring is showing signs of degradation, you really should buy new engine bay harnesses and change them.

 

I'm not getting anywhere with this diagnosis. I can't see any wiring that looks bad at all. This car has 72k miles and has never sat in the sun, etc. Absolutely, garaged, etc. etc. I have other german cars with 275k miles with NO wiring issues. Soooo, the only reason why I bring up the potential wiring is that it seems to have been a problem specific to this year car and other years from 92 to 96.
Does ANYONE have a picture of the engine compartment identifying the Electronic Throttle Actuator?? I see one obvious device in the center front of the engine directly in between the two distributor caps. The wiring to it is sealed with perfect insulation and doesn't seem to go back to the passenger firewall where I would expect it to connect to one of the computer modules, etc.
There are 3 obvious modules oriented from front to back against the pass. side firewall and 1 module oriented from left to right in front of them. I can't even determine which of these modules might control the ASR function. The diagnostic code shows a fault with the ASR yet the sensors seem to check out okay according to an experienced MB shop.
The wiring CD from Mercedes has "Star Finder" which shows a picture of the computer modules in the pass. side firewall area, but it doesn't even look like this car (R129 chassis).

Thanks in advance for any help,

Jeff

 

Not a 8cyl, but a 104 straight 6. Probably very similar to yours. Read the .pdf.

http://www.mbworld.org/forums/c36-am...sengaging.html

 

If I had something that looked like that bad wiring, I would be overjoyed at this point. I just don't know where anything that looks like that device exists in the engine area. Where is the ETA(s?) on the V8??

 

After a few days, I'm confident the wiring on this car is not the issue, contrary to a lot of bad information. I'm trying to narrow down the signals to/from the wheel speed sensors (VSS by the Mercedes wiring diagram CD). I still might need some information on the ETA, but I'm finding some information on that. I can't believe no one can provide a picture of the engine bay with some pointers as to where any components in question are.
Specifically, where do the signals from the speed sensors come into the ASR module??

Note to administrators of this site: I have searched for many terms in the S-class and SL-class catagories for "speed sensor", "VSS", etcetera, etc. etc. and I am finding nothing in spite of your professions. Possibly you can give me a hint...link, proper search term, etc.

Does ANYONE, know how to check the wheel speed sensor signals (mag. pickoff, etc.) and in what connectors are they are found?? ...I thought this problem was common (9/91 500sl ASR/ABS lights on once the car starts to move). I don't know how to be more specific.

Cordially and thanks in advance of any information.

 

at 4 places. Two are at connectors in the engine bay, at the firewall at the passenger and drivers side. You will measure a nominal 1000 ohms with a small a/c component if you turn the wheel and put your DMM on volts, a/c.
The (2) mounted in the differential can be tested an connector "E" and "D" at the multi-pin connector underneath the car slightly to the passenger side by the fuel pump and fuel filter.
I am finding an open circuit on the 2-pin connector "D", the 2-pin connector "E" is measuring 750 ohms nominal with a small a/c component when you turn the wheel-either one, since the differential is still installed.

Please provide any information to confirm, etc.

TIA

Cordially