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Look past the title - I have two x164s, which the wife has been driving off and on over the last period of craziness.
Last week, one of them triggered the ABS/ESP warnings, had very hard low speed steering (low speed steering valve switches off with ABS/ESP disabled) and would not shift out of Park. This was traced to an implausible signal from a Left Rear Speed sensor. 133k miles. Eventually the condition cleared she was able to motor off. Codes stored not current for ABS, ESP, and this is the fault memory:
This week, the other one's battery was flat so I let it charge overnight. Then, reportedly, it triggered ABS/ESP warnings with very hard low speed steering and reluctant to shift out of Park. Also traced to an implausible signal from Left Rear Speed sensor. 199k miles. Same behavior. Codes stored not current for ABS, ESP, and this is the fault memory:
Now in my rational mind, the odds of this occurring naturally is very remote. The only two commonalities here are both cars are very very sparingly driven.
Is this a typical low battery shenanigans intermittent fault? I have OEM speed sensors on order and the job's easy but I thought I'd throw this one to the crowd before breaking a sweat.
AS you know low voltage is not good for many control units and sensors. So I would say yes to your question and would check out both cars charging system
Both charge at about 14 volts and the latter one's battery is original, so that def could be it.
I've found other posts wrt wheel sensors and left rear failing first, so I gotta believe it's low battery low f.uc.kery.
I guess my question is; with a barely driven low battery x164 is LR speed sensor loss code usual/common?
Would love to sticky what codes happen in what order with a dying battery in an x164...if NASA could figure out a way around a Main Bus B undervolt surely we can map a course for a depleted/dying battery.
So - I do not think it’s a battery low caused failure.
I replaced both rear wheel speed sensors on the one car today, after having replaced the main and aux battery. The battery in it was 10 yrs old, but done.
It still threw codes with new batteries so off the wheels came and 15 minutes later I was done.
I am beginning to suspect it may have something to do with the overheat caution - either the brakes are dragging, or dear wifey was driving around with the parking brake on - both of which will generate enough heat to cook a sensor.
I will drive both cars this week to see if the problem persists.
So - I do not think it’s a battery low caused failure.
I replaced both rear wheel speed sensors on the one car today, after having replaced the main and aux battery. The battery in it was 10 yrs old, but done.
It still threw codes with new batteries so off the wheels came and 15 minutes later I was done.
I am beginning to suspect it may have something to do with the overheat caution - either the brakes are dragging, or dear wifey was driving around with the parking brake on - both of which will generate enough heat to cook a sensor.
I will drive both cars this week to see if the problem persists.
I had similar problem. I replaced all sensors and problem resolved.
Replace all 4 wheel speed sensors with Genuine Mercedes parts. Then perform a software update on the ESP control module. This is a very common problem on all X164, W164 and W251.
Common problem, ok - is there a commonly accepted root cause?
So far so good with the higher mileage one, replaced both rear sensors with oem equivalent (ATE) and no more error codes.
The lower mileage one persists in throwing random ESP/ABS off events.
07-08-2020, 07:51 AM
