Of course, the moment I finished my Audison project, I had to acquire a new surprise.

I have:



* ABS/ESP Inoperable
* Tire Pressure sensors inoperable
* Speed control inoperable
* HOLD inoperable

I have taken the car to the dealer and they advised that XENTRY says right/front ABS sensor defective.

Replaced both front sensors with new original sensors, drove home (30km) no problems. Got back in the car couple of hours later to go see Jurassic Park 2025 edition, (terrible film - don't waste your time) and low and behold I have ABS/ESP again.

I'm thinking the following:

* Wiring harness towards ABS sensor, this is highly unlikely as this is a *very* clean car, has never seen mud, and is never left dirty (undercarriage). This car is ice-cleaned underneath once every year to eliminate any thought of it rusting, etc.
* ABS Module itself, seems to me as a highly unlikely case as well, I don't feel the car is old enough to have modules like this failing
* Encoder ring in front/right wheel bearing - this, I can totally see happening for some reason.
* Steering Angle Sensor - if I had this, it would have generated a code for this

Now some other facts, which while I don't think are related, they are relevant to how I'll investigate this case:

* The car was at Audison for several days, and I'm certain they drained the batteries hard, even though the power charger (integrated Mercedes 230V charger) was shown & asked to be used
* All modules in the car had severe undervoltage/low power alarms

Although having said the above,
* Battery is genuine Mercedes, 1 year old, and holds 13.8V
* Alternator/Generator is newly refurbished (Q1 2025)

--

I'm annoyed I have to deal with this but sometimes life give us new challenges.

While I am obviously keeping the fact that the car was somewhat worked on during the Audison job, I don't see any plausible connection between replacing speakers, adding two amplifiers, and ABS becoming suddenly inoperable.

I could see this being the case if I couldn't communicate with the ABS module, or if all sensors were showing faulty - or if ABS would *never* work at all (it fails after 15-20 minutes post-start) -
It is nonetheless something I will keep in my mind while I go through this job.

Car is *ultra* well maintained, only original MB parts, goes to the dealer at the slightest inkling of a problem. Distance travelled 201700KM (126000 miles)

If anyone has any ideas I'd be glad to hear them!
Thanks!

 

another thread in the last week....


check here - if the diagnostics and the parts used were legit - you could try from this one..... https://mbworld.org/forums/s-class-w...ml#post9193440

 

In a way, this is like driving my 1983 W123 again.

With that vehicle, you knew, that if you didn't drive properly, you would lose (flat spot) 4 x tires if you had to brake unexpectedly.

This has the unintended positive side effect of even *better* fuel efficiency, and even safer driving than usual.

Now, a panic stop will result in 4 x Michelin Pilot Sport 4's being destroyed, and a minimum of >1500 EUR replacement cost. As a result, speeds are even lower, distances are huge, and much more attention is paid to what's going on.

This is just like having my W123 back. I don't like it, but I do find it amusing.

The car will be at the dealer in a few hours and we will start afresh with more diagnostics.

I need to buy my own XENTRY as I have >4 MB's that I either own or manage, and it's time to be able to do basic diags myself. I think that this situation will be the catalyst for this project.

 

Intermittent ABS faults after driving point to a failing encoder ring or voltage issue from the recent battery drain. Check live sensor data when the fault returns likely the right front drops out. Swap bearings to confirm. Less chance it's wiring since the car's clean. Unrelated to the audio work unless a ground was disturbed.

 

Car went back to dealer this morning, and of course same fault, front/right ABS sensor implausible signal.

I hope that it's just the wiring harness and/or plug where the sensor plugs into the car's body electronics..

I have directed them to investigate this first, then we can see about further works. As much as I think it might be the magnetic ring in the bearing, I'm not so sure.
All of this doesn't sit right with me at all, the car was sitting for 10 days with the audio jobs, and then we have ABS.

This incident will result in me looking for an on-premise XENTRY solution. I have seen BenzNinja's website in the past and will reach out to him.

 

charge the battery - they go mental if its a millivolt below whatever insanity they decide they want today

don't ever be surprised by odd goings on and random issues with a 221 its their hobby - and they take it very seriously

 

Read my post in the other thread you were posting in. I write about the unsoldered pins in the CGW.

 

...Arrie I know you are keen on this solder job and glad your car works - but its not an omission or a deliberate failure point Merc built in the CGW - its necessary feature of canbus technology where they intentionally didn't want to corrupt data flow

maybe in the good old days of silver or dangerous lead soldering the electrical conductivity isn't messed up enough to matter ?

BMW do not allow a single soldered connection on their cars
Clearly for this critical data comms element in the main network controller of the car, Mercedes Benz agree entirely with that engineering solution - soldered joints (certainly with modern junk solder) alter the electrical integrity - where a crimped connection doesn't

 

Nobody called from Mercedes today.

I didn't call them either.

I'm starting to become a bit afraid.

I feel this may become some kind of nightmare.

I *REALLY* hate it when things like this happen. I prefer easy to fix faults, i.e. piston out of the block, transmission failed, differential seized, etc. This type of electrical insanity - I just hate it.

I much prefer physical /BROKEN/ things that you can see, fix, and move on. These little hidden demons enrage me.

 

Don't tell me you believe what you just wrote, please!

The ONLY reason they don't solder the pins is it makes it faster and cheaper to manufacture the part.

Unsoldered connection allows oxidation between surfaces over time and this if anything leads to bad connection. I had my dash lit up like a Christmas tree with all sorts of errors with different modules. After soldering job EVERYTHING went good again and nothing else was done for fixing it. Tell me about what connection is better...

 

I was not saying your CGW didn't appear to have a fault nor that the solder job might have resolved it

but I don't think recommanding everyone potentially damage their working one to try a fix that might mess it up



.

 

I got a call from Mercedes, they're delivering the car to me now. Ready to go.

Cost about 150 EUR with parts & labor in.

Problem was the magnetic encoder ring/disc on front right wheel. Fortunately this is separate from the wheel bearing, and as such was cheap and easy to deal with.

We can consider this issue closed!
Thank you all for your assistance!

 

False hope

The car goes back, ABS light came on as they were delivering it to me.

I sense a nightmare coming..

 

the inner wheel bearing seal is the reluctor at the front - it can't really go wrong unless damaged - its can build metallic disc crud - but they don't seem to misread even then, if the bearings are loose it wouldn't help

 

I don't understand how a dealer can't know.

 

I don’t recommend this job to everyone, just everyone who knows how to solder.

This is very easy soldering job. No heat sensitive components close to the pins. Very low chance to botch it.

But all for him/herself.

 

Mercedes did the following:

* pulled new wires with new pins from the ABS computer to the ABS sensor plug
- this eliminates the possibility of any chafing or problems there

* replaced the entire wheel hub from a spare car that was wrecked (thanks Mercedes)
- ABS light still comes on

* they will recode the ABS computer from the spare / dead car into mine, and test it
- waiting for this

The *only* error is the Front Right ABS sensor. They drove it, with live data from XENTRY, all 4 wheels show movement until the front right stops showing speed and drops to 0 KM/hr, which of course results in ABS light.

They suspect the computer has malfunctioned, it's only a single wheel sensor that goes off, the ABS computer does *NOT* issue CAN warnings, and the central gateway does not show the ABS computer going offline, simply the ABS ECU sees the front/right wheel going to zero speed.

 

Could have zapped it or some funky voltage spike during that monstrosity of a stereo install. No bid deal, they've got it narrowed down.

 

These are the consequences of *BASS*

If it's the computer I'll just buy a new one and call it a day

Thanks @Senecat

Even with this noise, it was worth it.