W140 S500 ABS light and dim ASR light no codes

[ivan1983]

Hi there,

I wonder if anyone can help.

My W140 has the ABS light on constantly and the ASR light is dim ( It almost looks likes it being lit by the ABS light).


I have cleared the previous codes using STAR and there are no current codes any ideas?

The light come on with the ignition (including dim ASR) and do not go out.

Any ideas?

Thanks
Ivan

 

[ivan1983]

I was wondering if anyone has any ideas around this?
I dont want to start buying control modules randomly in the hope it sorts it.

Upper wiring harness and throttle body harness have been replaced.

Thanks
Ivan

 

[WDB124066]

Low voltage warning? How old is the battery or OVP relay for that matter...

 

[ivan1983]

Low voltage warning? How old is the battery or OVP relay for that matter...

Battery is fairly new, resting voltage is around 12.5v or higher from what I remember. I will double check though.
It was measuring ~14v across the terminals with the engine running.

With regards to the OVP relay I found conflicting info on if the W140 has one. I think that it might be controlled by the General Module.
Incidentally the General Module looks to have been replaced the current part number is 014 545 36 32, all fuses in the module seem good too

 

[WDB124066]

Check the wiring inside the throttle body for damaged insulation and the reostate for smooth operation.

Check seatbelt latch wiring as well.

 

[ivan1983]

Check the wiring inside the throttle body for damaged insulation and the reostate for smooth operation.

Check seatbelt latch wiring as well.

I rewired the throttle body due to corroded insulation , prior to doing that I had all sorts of codes!

I will look into the seat belt latch wiring, I didnt realise these were wired. I knew there is some wiring for pre tensioners on the reel but not on the latch

 

[WDB124066]

On a 124 there is a wire to the latch to let the brain know the seatbelt is in use. I had a light go on due to this once.

Other past problem areas are clogged wheel sensors or issues with wheel sensor wires from memory.

 

[ivan1983]

I think I need a wiring diagram for the ASR, ABS and Egas modules so I can test for resistance and continuity, does any have access to them?

I also need to change the title of the thread as I sometimes get codes
Summary of the car which is new to me and was not running so I have no history on how it ran
It looks like the ASR bulb has been removed and appears dimly lit due to the ABS light being on

New upper wiring harness
Rewired throttle body
ABS light (assuming ASR light too) is on when ignition on and does not go out
Car sometimes does not start on first crank when warm, always starts on 2nd crank
Battery newish- Car has good resting and running voltage
Brake light switch operates correctly when viewed through star
When viewing live values through star all looks good

Some of the codes I have seen inconsistently are
017 CAN: No reception from EFP,TPM,LLR N4/1, N4/3, N4/4
018 Magnets for crankshaft position sensor L5 not recognized
028 CAN: No reception from EFP,TPM,LLR N4/1, N4/3, N4/4
030 CAN: No reception from EFP N4/1 or fault in EFP
112 CAN: fault in transmission from EFP N4/1

 

[ivan1983]

Anyone have info on the resistances I should expect to find on some of the circuits?

I have found diagrams here but it doesn't suggest what values to expect

http://www.autolib.diakom.ru/CAR/Mercedes-Benz/1994/S500/SYSTEM WIRING DIAGRAMS/

 

[ivan1983]

Managed to sort it.
I read on a another forum about one guy who found the coffin case was somehow out of alignment causing the modules not to seat properly.
I removed the case and seated the modules directly into the connectors, fired it up and no lights!
Screwed it back together with modules in situ and no lights!

Its work noting on UK models you dont need to remove the wiper and associated trim and the smaller bolts that hold the coffin case to the socket base are captive so you dont have to worry about loosing them.