1992 400E ABS / ASR rear sensors

[grmichaelj]

further to the other post about the lights on the dash, the error code in the computer was right rear sensor. I called the local dealer and got one coming - they took my VIN and said they would get it coming. 1 of 19 left and all of them in Germany. If anyone wants to control the market for rear abs sensors...

And so today my mechanic is working on it doing a few other things and he checks that sensor to see if it maybe the wires... no such thing as a rear right, or left for that matter, only the one in the rear diff...

Was ist los?

Michael

 

[gsxr]

And so today my mechanic is working on it doing a few other things and he checks that sensor to see if it maybe the wires... no such thing as a rear right, or left for that matter, only the one in the rear diff...

Was ist los?

Michael

Cars with ASR have 2 rear sensor, one for each axle.

Cars without ASR have only 1 rear sensor, at the pinion (input) of the differential.

ASR (traction control) was optional on the 400E/E420. But if you provided your VIN to the dealer, they should have known if your car did not have ASR, and only had one sensor.

Note the error code translation sheets vary between ASR and non-ASR. There is no code possible for rear left/right sensors on cars without ASR.

 

[grmichaelj]

This one has traction control... Is there also a sensor on the differential or it's either one single or two, one on each side...?

Thanks!

 

[gsxr]

This one has traction control... Is there also a sensor on the differential or its either one single or two, one on each side...?

Without ASR traction control there is ONE sensor at the front (side) of the differential, measuring input shaft speed.

With ASR traction controls there are TWO sensors at the top of the differential, measuring left and right output shaft speed.

Something isn't matching up here. Either your mechanic is wrong and there are 2 sensors, or your ASR car ended up with the wrong differential.

Assuming this is your 1992 400E with 5.0L engine, what differential is in there? Stock, or was it changed to lower gears? If changed, who sourced and installed the diff? Etc.

 

[grmichaelj]

We left it stock, and the traction control does work... I'm guessing he didn't see the other one...

 

[gsxr]

We left it stock, and the traction control does work... Im guessing he didnt see the other one...

OK - yes there are two, and both are difficult to access without dropping the diff. There are clearly 2 wires going up to the top of the diff though. Sensor failures are stupid rare, much more likely is a wiring issue, or module issue.

Looks like this:

 

[grmichaelj]

Thanks for that! I do have one coming but I'll talk with him next week to see if he wants too take another look at the wires. Can you jumper some new wires in?

 

[gsxr]

Thanks for that! I do have one coming but Ill talk with him next week to see if he wants too take another look at the wires. Can you jumper some new wires in?

Depends where the fault is. If the wire is intact, it's more likely at the connectors somewhere along the line. Another forum member was chasing a similar problem and found wiring issues below the CAN module.

 

[grmichaelj]

Ok, thanks, we'll check it!

 

[grmichaelj]

So, I am seeing that when the car is cold, or has been sitting, the ABS and ASR lights stay off and I am assuming the ABS works fine. After about 4 or 5 miles, the lights come on and stay on, no matter what I do - restarting the car usually was enough to reset it but not anymore. Are we leaning in the direction of wiring and not sensor with this behaviour?

 

[grmichaelj]

Ignorant question, CAN module is the location of all the modules LH, ESA etc... on left firewall or the EZL and stuff on the other side of the engine bay?

 

[gsxr]

Ignorant question, CAN module is the location of all the modules LH, ESA etc... on left firewall or the EZL and stuff on the other side of the engine bay?

Yes, the CAN box has all the powertrain modules inside (LH, GM, ASR, E-GAS).

The EZL is the only module not located inside the CAN box.

(I'm assuming your 92 400E doesn't have a check engine light or diagnostic module, but if it does, this 'watchdog' module is located ahead of the passenger footwell by the alarm modules.)

 

[grmichaelj]

I don't think it does have a check engine light... And the plug for diagnostics is three large round one up by all the modules...