I have a 2008 S550 that was just returned from a wheel bearing replacement situation. My wife picked up the car and was told that they could not get the ABS & ESP dash indicator light to turn off. I have left it sit with the key off overnight, but they return when I turn the car on in the morning. I have checked the output of the alternator and it is 14.4 after sitting all night. I replaced the starter battery in Feb. this year and the systems battery last summer. I am a little afraid of disconnecting the batteries to see if the system will reset as it may require to be reprogramed. The repair shop supposably did not do anything electrical only R&R the front wheels. Can someone weigh in on this, hate to take it to a Dealer as in the past they want to charge me for their lack of basic knowledge, (4 hours to figure out the systems battery was bad so the control system was dead) appreciate the help lets share the knowledge with your response so others can learn.

 

those cars are known to have issues with the wheel speed sensor harnesses. In your case you shouldn't need to reset anything. also if you have the wrong tire sizes, it can cause an esp light also.

 

Chassis 221
Appreciate your input, thinking about it now it makes sense driving from Calif. to get to Tenn. in heavy rain the ABS light came on in two occasions, but canceled after the storm and shutting down the car for a while. The tires are different as it does have stagger and it was found that while the work was being done the rear tires were up front and etc. Spent 5 hours in Palm Desert having the rumbling sound checked out at a national tire store whom I had purchased the tires from at a No-Calif. location.


They didn't find anything wrong but did manage to put the tires back on wrong. I had earlier in the day had the car checked out at an independent M/B center in Palm Springs that told me I had a problem with the tires. The noise continued until the bearings were changed out, but the ABS and ESP lights are on. Going to an independent shop this AM to put it on their computer.


I should mention to all of those who are reading this post, last year I had a 4 wheel alignment did still didn't feel right so I jacked it up and found slop in the wheel bearings don't know how you can do an alignment with loose bearings. I replaced the bearings as they did not look good and one of those new bearings had surface flaking, no scoring, but pieces that came off so I had those replaced this week.


Last year I was in Louisville (Derby Day) and replaced the rear tires, back tracked 15 miles to get the right size, then without checking (my fault) we left only to discover that they sold and installed the wrong size, front tires size instead of rear, you have to check what these guys are doing, make sure they get it right.

 

A follow up for those that might have interest, the independent shop did a print out on what was stored in the cars memory. Then erased it, drove the car and printed out the new data, reoccurring fault was as Chassis 221 had stated, wheel speed sensor, the harness on the front left side has failed. Parts are ordered and I will do the work myself, don't want chance it with anyone else. I have never in 60+ years seen a bearing fail like mine, they didn't return the race or the outer bearing and race, so my conclusion is incomplete. I do not know yet why the harness would fail while in their care, they should not have been close enough to touch it. Perhaps it is age, this car has 70,000 miles, I think too young for this kind of problem.

 

Didn't have time to install the harness myself as I had to leave town. So I had the last shop put in but it didn't change anything. I was told by separate email that it could be the reluctor, and if that is the case beating on the hub without supporting it would allow the reluctor surface to be destroyed. I was told in this email that the part was only $18.00, the dealer out here (now in Calif. for 2 weeks) who didn't know what a reluctor was, then after research said it was part of the $300.00+ hub. Does anyone have a part number for a reluctor for this car?, maybe it is a separate part! By the way keeping with tradition, my son reports upon picking the car up for me that my floor mat is covered with grease, that makes 6 screw ups out of 7 shop visits.

 

I'm not totally sure which set up is on your car, but some cars have a magnet in the wheel bearing race. which picks up the wheel speed.If the bearing is installed wrong, you could still have an issue. there is only a magnet on the one side of the bearing, you have to check it before installing it. or the reluctor wheel or tone ring will be on the axle CV joint.(looks like gear teeth) I have seen just a few weeks ago a 2009-2011 S class that had a constant issue with ESP lights. all 4 wheel speed harnesses were changed out. and also an ESP control unit installed. customer said the ESP light would still come on.I then found error codes for the left rear wheel speed sensor. I swapped the left and right rear axles and the problem moved to the right rear axle. I removed the rear axles and found the reluctor wheel had gotten a gouge from a stone or something. after installing a new axle the problem went away. This is not to common for this to happen. your situation could be different. I don't think you can just get a reluctor wheel on the CV joint from Benz as a separate part. and usually you cant just get the CV joint either, you usually need to buy the whole axle. If I was you I would take it to a Benz dealer. Ive seen many different issues with ESP lights. could be a broken wire somewhere.

 

Chassis221;
Thank you once again for chiming in, you input is appreciated. My, it is actually my wife's car, I told her it will make her look 20 years younger with the all black, wheels, grille and etc. AMG package, but I take care of it. This car is a RWD so it has std. 2wd front hubs, I was on a independent MB shop's computer and may have found a part number, 221330025, which may or may not be good, I will go back to the dealer this afternoon (PST) and see if I can get them to check out the number. My parts drawing shows a part that could be a reluctor or a seal as #30 but it is included under a symbol linking it together with the hub as #20 combined. This is not my hobby car but I seem to be making a career out of it, whether I like it or not.

 

chassis221;
Met with the parts manager at our MB Dealer today and he verified that part # 2213300225 is correct for the bearing with a built in reluctor. Leaving for Tennessee where the S-550 is Wed. and will have the install shop order it and install same. It seems that Dealers want to sell a complete hub with bearings instead of bearings only. Out of all the MB Dealers in the San Francisco bay area there is stock for this bearing in only one location. Thank you again for your input, I hope our exchange saves others a great deal of grief if they have the same problem.

 

I returned to Tenn. to solve the ABS-ESP light problem and took the wheel hub assembly apart myself. What I found was even though I was invoiced for two replacement bearing assemblies, but only received the inner bearing. The old scared up outer race was still in place and the inner bearing would not come off the spindle holding the seal behind. The seal is actually a reluctor, if you lay it on a steel flat surface it will stick. To reassemble the wheel/hub I used the stuck inner bearing to center things so I could try to start the seal into the hub. No way could you push the seal flush to the hub back surface to allow correct impulse reading by the pickup. I really couldn't tell them I had been inside to inspect what had been done. Visited the Tire Store to talk with the Manager who was not in, but did chat with the floor manager and the "Tech" that did the work. I was informed by him that he replaced all the bearings, setup a meeting with the Store Manager for the next day. I had learned prior to meeting that the Chain Corp. will fine the Store Manager $1000.00 for proven complaints. I did allow my copy of a consumer complaint form slip from my package to the counter and told them that if I had to have Mercedes fix it and I was going to have to come after them. My meeting with the Store Manager the next day went very well, I was allowed to witness the teardown, point out the problems, received full reimbursement for the harness expenses and helped them get the right outer bearing. Bearing/auto parts stores will show a A12 while a Timkin 28740 or Centric 41035007 or a National ? 32205 are what is needed. The inner bearing is a SKF, Timkin and others 32008, the seal/reluctor is a Napa # 0259971647. It is also available at Mercedes (# ?) for $18.00 retail, reference # 30 on their exploded parts view for the W221 RWD front spindle.