Speed sensor 2012 S550 4matic front right
Thread Starter
Junior Member
Joined: May 2013
Posts: 16
Likes: 2
From: East Tennessee, Northern California
1984 380SE, 1986 560SEC, 1988 560SEC, 2005 S430, 2005 SL500, 2012 S550 4matic
Speed sensor 2012 S550 4matic front right
So, I have a 2012 S550 4matic. I replaced the right front passenger side air strut. Now I have the ESP ABS inoperative warning light. The suspension is stuck in sport mode. Code says right front speed sensor. I have replaced the sensor and still have the problem. I now believe the problem is the tone/reluctor ring. I am not able to find what I feel is reliable info. It seems the tone/reluctor ring is in the pressed bearing? I would like to buy a wheel hub bearing assembly and just swap it out, but the assembly I'm able to find is for base model and not for 4matic. Am I correct in my assumptions? Any info and help is appreciated!
Super Member
Joined: Jul 2014
Posts: 992
Likes: 245
From: Tucson, AZ
'20 X5 M50i; '17 Ram 3500; Golf Cart; Bikes; Scooters
A lot of posts here state that non-OEM sensors will have errors. Did you use MB sensors or something else?
If not OEM, get one from MB and see if that fixes your issue. Let us know what happens.
If not OEM, get one from MB and see if that fixes your issue. Let us know what happens.
Thread Starter
Junior Member
Joined: May 2013
Posts: 16
Likes: 2
From: East Tennessee, Northern California
1984 380SE, 1986 560SEC, 1988 560SEC, 2005 S430, 2005 SL500, 2012 S550 4matic
I did use OEM sensor as a replacement. Same error code on old and new sensor. I believe when I split the arms to install the new air strut, the shock probably caused the tone/reluctor ring to be damaged. I'm just having a hard time finding specific info for my model year (2012). Apparently the tone rings are a bit different design from year to year. Looks like for my car, the ring may be in the wheel bearing which has to be pressed out old and in new. I was hoping to find a wheel hub assembly that already has the bearing pressed in and just do the swap myself. But, all I am able to find (google) is this assembly for a base model and not for the 4matic. Thanks so much for the help.
Member
Joined: Jan 2011
Posts: 212
Likes: 70
2003 S55 (SOLD) , 2012 S550
I had the same error on both fronts before. If you are running OEM Brake Pads then take off the wheels and sensor and pressure clean the sensor wheel. On my car both sides where caked up with brake dust and after cleaning the error never came back. When the pads were due i also switched to Akebono and dust is no longer an issue.
Good luck.
Good luck.
Thread Starter
Junior Member
Joined: May 2013
Posts: 16
Likes: 2
From: East Tennessee, Northern California
1984 380SE, 1986 560SEC, 1988 560SEC, 2005 S430, 2005 SL500, 2012 S550 4matic
Thank you! Great idea. I will try that. Almost time for brake pads anyway. Thank you guys for the responses!
Super Member
Joined: Jul 2014
Posts: 992
Likes: 245
From: Tucson, AZ
'20 X5 M50i; '17 Ram 3500; Golf Cart; Bikes; Scooters
Akebono Euro pads front and rear. Amazon has best prices.
Clean the wheels while doing the pads and you will only need to rinse the them the future. Huge difference.
