Sensors on a MB CLA 250, what's going on?!?!

[Inderpland]

Bought a CLA 250 a few years ago and, boy, did I get a real lemon. But that's a story for another day. One of the many problems I've had are the tyre pressure sensors for the run-flats. Yet again (and of course always when faaar away from the nearest authorized garage) a sensor for one of the run-flats have become faulty/broken and when that happens the whole alarm panel light up; tyre pressure, engine malfunction, ABS, automatic parking brake alarm and stops working, power steering stops working.

I've tried asking the few that talk any English at the dealership/garage how come all this happens just because a tyre pressure sensor breaks but have not gotten any answer.

Does anyone on this forum have any idea why this happens?

[FarangRimPing]

Not really answering your question but my wife has a 2019 GLA250 and it has been perfect, except for the wheel sensors! Luckily, most failed early on so the replacements were free. The dealership is really on the ball and the replacements were done immediately after we drove the car there without an appointment. I THINK it was a bad batch manufactured at that time as the replacement sensors seem fine. BTW, we recently replaced the original run flats with Michelins and I'm happy that we did.

 

Edited yesterday at 01:54 AM by FarangRimPing

[The Theory]

23 hours ago, Inderpland said:

when that happens the whole alarm panel light up; tyre pressure, engine malfunction, ABS, automatic parking brake alarm and stops working, power steering stops working.

IMO 

the tyre sensor could be ok, but a common harness could be the problem (if all those wires go through 1 harness). 

[Lacessit]

23 hours ago, Inderpland said:

Bought a CLA 250 a few years ago and, boy, did I get a real lemon. But that's a story for another day. One of the many problems I've had are the tyre pressure sensors for the run-flats. Yet again (and of course always when faaar away from the nearest authorized garage) a sensor for one of the run-flats have become faulty/broken and when that happens the whole alarm panel light up; tyre pressure, engine malfunction, ABS, automatic parking brake alarm and stops working, power steering stops working.

I've tried asking the few that talk any English at the dealership/garage how come all this happens just because a tyre pressure sensor breaks but have not gotten any answer.

Does anyone on this forum have any idea why this happens?

It happens because Mercedes no longer makes quality vehicles. The Japanese and Koreans are better quality for a cheaper price.

 

The glory days of Mercedes were back in the 1980's, since then the Stuttgart bean counters have taken over from the engineers. Trading on former reputation.

 

Perhaps the OP has already noted service and repair costs are 2-3 times higher than the Asian brands.

[HauptmannUK]

I part own a car sales and service business in the UK (established many many years ago by my grandfather). For the past 25 years we have specialised in MB and BMW.

The sensors used in MB's direct TPMS are supplied by Hamaton, a Chinese company (also with manufacturing in UK, USA and Germany). These sensors have a life of around five years, so they must be considered 'consumables'. We supply and fit Hamaton-branded aftermarket sensors (identical to the MB-branded part, but much cheaper).  They automatically calibrate to the head unit after about ten minutes of driving.

One of the quirks of recent MB fault monitoring software is that it tends to throw up additional warnings that are not obviously connected to the actual fault. For example, one common issue for us is a fault with the electric handbrake that throws up simultaneous ABS, EGR and ESP warnings. Owners call in saying they have an EGR fault whereas its actually a seized handbrake motor.....Very illogical. Most MB software is written in India these days - maybe that has something to do with it.....