Wrong ABS sensor damaged ABS ring

[Steve260E]

Hello, I recently fitted a new genuine MB ABS sensor to my 2006 CLS C219 320CDI and found that the ABS/ESP light remained on, upon further inspection the ABS ring had corroded and had become detatched, yesterday I fitted the new ABS ring and all seemed to go well, upon the first test drive the ABS/ESP light went out momentarily but came back on within seconds, took a speed reading from icarsoft at problematic sensor and once again it was reading 0mph when the others were reading correctly.

Took the sensor out to inspect and it appears that the sensor is slighty longer than the original by about 2-3mm and as a result it has fouled on the new magnetic ring and gouged away the rubber part, you can clearly see the wear on the end.

Has anyone had anything similar to this? This sensor in particular was listed as compatible with a 2006 C219 CLS with part no: A2115401217

 

[Jobsworth]

Did you make sure you removed every bit of the original magnetic ring before fitting the new one? If there’s a bit left underneath this can happen

 

[pmcgsmurf]

You don't say what the part number of the new sensor is or where you got this.

I'm assuming a Mercedes dealer, I'd take both parts in and show them to parts department or if mail order send them side by side pictures.

If you've bought from an online factor and got a "compatible" part this can be one of the risks.

 

[Steve260E]

All the old magnetic ring was fully removed yes thanks, both the drive shaft end and the inside of the hub were thoroughly cleaned before refitting.

I've just noticed that the part number of the new sensor is A2115401217, part number of the original sensor is A2115402417......it appears that I haven't carried out my usual due diligence when fitting replacement parts and despite both part numbers cross referencing as the same they obviously are not hence the slightly longer sensor, silly me!

Thanks for your advice, luckily I have a new spare ABS ring to go on, stripping the rear hub again is going to be torture!

 

[pmcgsmurf]

A 211 540 24 17 ROTATIONAL SPEED SENSOR REAR AXLE,LEFT AND RIGHT
Replaced by: A 211 540 30 17

 

[PolishGeorge85]

Front or rear sensor have you done... there must be a reason why this part number are different. And only one thing that comes to my mind is that part is correct for the car but wrong END of your car.

 

[Steve260E]

Its the rear sensor in question, mixing front and rear sensors is impossible as they are a completely different type of connector, as pmcgsmurf pointed out the part number although very close was wrong and infact needed to be the revised sensor A 211 540 30 17

 

[OneForTheRoad]

I'm a bit surprised the longer sensor bolted down ok . ??

 

[Steve260E]

I'm a bit surprised the longer sensor bolted down ok . ??

Yes that surprised me too but it did indeed bolt down flush