ABS, EPS light on 2005 500E 4 matic

ABS, EPS light came on and the dealer/repair guy says its due to faulty steering rack valve and estimate of $1040 to repair.

6 months ago I had complained of same and the dealer/repair guy said it had to do with faulty brake switch part of a warranty problem. He fixed it but its back again. Now he says its do with faulty steering rack valve. I am not sure these things are connected but it seems thats the error code that pops.

EPS/ABS light does not come on all the time. It comes occasionally and the steering wheel seems like it has no power assist.

Any help here?

Let me give you an update.

  1. The dealer said its to do with battery since message comes on saying “multi function mal function due to low battery”. So I asked them to replace it before replacing the rack valve.
  2. They did not listen to it and replaced with battery and with rack valve and a bill for $1400.
  3. I went to collect car and the same lights ABS, EPS and tightness in steering come on. So problem not solved but hit with big bill.
  4. Dealer is redfaced and says will work on it.

What is going on? Can you suggest?

Did you authorize valve replace?
Why are they red faced if you told them to do it?

We need the exact fault codes. There are TONS of fault codes which can cause the ABS an ESP light to come on. I believe you meant ESP and not EPS, correct?

It sounds like your car has speed sensitive power steering, and it’s apparently not working correctly

yes, there is a separate valve/solenoid on Benz racks that have this feature

The faulty brake light switch causing the warning lights to come on is a very common scenario.

And it’s entirely possible that each time the warning lights have come on, it’s been due to a different component

Another common culprit is the steering angle sensor . . . that would most likely cause both the ESP and ABS warning lights to come on

No Mercedes experience, but when both the ABS and stability system warning lights turn on on some other cars, that can mean the computer has detected an engine performance problem. It turns those systems off (and turns the warning lights on) so you know those systems aren’t working. In addition to an engine performance problem, this could be caused by something as simple as a faulty battery, alternator, or wheel speed sensor. As mentioned above to get to the bottom of this you’d need to post the actual diagnostics codes here. A power steering problem could cause this as well. If the dealership believes the problem is in the steering, about all I can add is that — having the actual car in their shop and presumably having lots of Mercedes diagnostic experience — they are in the best position to make that determination. As long as they keep working the problem until you are satisfied w/the result, that’s all you can ask.

I did authorize the steering rack valve replacement but only on condition that they first replace battery and check. REason is that ABS , ESP and tightness in steering always happens at same time. And then it goes away all together. The message on the screen use to be some functions are malfunctioning due to low battery. IN the past I have checked battery and it was fine. Now these guys replaced it and replaced valve without checking after battery and when I go to pick up car the same squence happens.

I would presume because they did an expensive repair that didn’t solve the problem. As for telling them to perform the work, the OP authorized the shop to replace the battery and see if that solved the problem. They went ahead and replaced the valve on their own and the problem is still there.

They kept the car for a week with a free loaner to me and now they report no issues, Its all been solved. Jerks. They replaced a rack valve when they should not have. Battery would have sufficed. Now I cant do much.

How do you know that the technician didn’t replace the battery and found that the steering problem continued, then performed the steering repair?

According to the OP, the tech performed the steering repair first, then replaced the battery when that didn’t correct the problem. If that’s the case he has a right to be upset.

This is what happened. When the car was delivered to me after repairs 10 days ago it flashed the same message ABS, EPS warning and steering valve got tight. The service manager mumbled some one must have left the lights on and battery may have lost charge. To which I asked him the pointed question - if battery is the issue then why change rack valve? He said dont worry take the same MB loaner and leave the car with us and we will check everything out. So for the past week they have had my car to test and I have had a brand new loaner. Today they called me saying car is fine and no such message etc. No explanation as to why? I think the Tech screwed up and the service manager is covering up.