ESP warning light- inoperable!

[HelenT]

Hi,
I’m new to this site so apologies in advance if I am posting in the wrong place.
I have a 2013 SL350 auto.
About a mile 1/2 from home the EPS (traction control?) warning light came on, also saying inoperable. The power suddenly dropped off and then engine starting surging. I managed to limp home in it, not allowing me to do more than 10pm.
Can anyone tell me what might be wrong with it. I have not chanced going out in it but I have turned it around in my drive and it did behave as normal without the warning light coming on again. I can’t get hold of my mechanic but it is due to go in tow Mercedes dealership for servicing on 10th May.

 

[markjay]

Welcome.

If the car has been previously serviced by a Mercedes Benz dealer in the past 12 months, then you are entitled to free Mobilo roadside assistance service.

If you call them, they'll dispatch a mechanic with MB diagnostic equipment who will read the fault codes and will be able to advise what the issue is.

The telephone number for MB assistance can be found on a sticker on the door sill on the driver side. You may need to tell them that due to the issue you experienced, you are reluctant to use the car until it is checked and confirmed to be safe to drive.

(Mobilo cover includes towing the car to the nearest MB dealer, though it your case this will probably not be required)

 

[HelenT]

Hey Markjay!
Thanks for your prompt reply! Sounds like good advice to me, I will give it a go - Thank you!!

 

[BlackC55]

Its probably a wheel speed sensor issue.

 

[HelenT]

Ah ok, will let you both know the outcome- thanks BlackC55

 

[geoffus]

Yes similar symptoms when a wheel sensor packs up, if it is, it's a fairly cheap fix.

 

[markjay]

Yes similar symptoms when a wheel sensor packs up, if it is, it's a fairly cheap fix.

Would a failed wheel sensor put the car in limp mode? And would the fault be intermittent? As far as I know it only disables ABS/ESP, and once this happens the fault remains. What have others experienced?

 

[geoffus]

On the wifes car it put the car into limp mode, the steering went heavy and the ABS/EBS light came on.
The car went really slow and wouldn't change gear past 4th I think, other lights came up but can't remember which ones.
I managed to get home and then reset the EML with Icarsoft, the car then ran normal again till I reached around 25mph and it then went back to limp mode. After several attempts it was found to be the magnetic bearing on the nearside wheel, the impules were not picked up by the wheel sensor, the symptoms are the same as the sensor packing up.

 

[HelenT]

On the wifes car it put the car into limp mode, the steering went heavy and the ABS/EBS light came on.
The car went really slow and wouldn't change gear past 4th I think, other lights came up but can't remember which ones.
I managed to get home and then reset the EML with Icarsoft, the car then ran normal again till I reached around 25mph and it then went back to limp mode. After several attempts it was found to be the magnetic bearing on the nearside wheel, the impules were not picked up by the wheel sensor, the symptoms are the same as the sensor packing up.

Interesting Geoffus, it has reminded me that I’m sure I got a non urgent advisory that had something to do with, I think the shock absorbers, or maybe the bearings on something or other on last years service
I have had several other commitments today but will call MB Roadside assistance in the morning now. Thanks all!

 

[leef44]

Would a failed wheel sensor put the car in limp mode? And would the fault be intermittent? As far as I know it only disables ABS/ESP, and once this happens the fault remains. What have others experienced?

When my wheel speed sensor failed, it did not go into limp mode. It stayed on, not intermittent. It disabled ABS, ESP, cruise control and brake hold.

It was like driving in the old days

 

[leef44]

Welcome.

If the car has been previously serviced by a Mercedes Benz dealer in the past 12 months, then you are entitled to free Mobilo roadside assistance service.

If you call them, they'll dispatch a mechanic with MB diagnostic equipment who will read the fault codes and will be able to advise what the issue is.

The telephone number for MB assistance can be found on a sticker on the door sill on the driver side. You may need to tell them that due to the issue you experienced, you are reluctant to use the car until it is checked and confirmed to be safe to drive.

(Mobilo cover includes towing the car to the nearest MB dealer, though it your case this will probably not be required)

I thought you only get Mobilo roadside if you are in their service package. I didn't know this.

 

[markjay]

I thought you only get Mobilo roadside if you are in their service package. I didn't know this.

Mobilo roadside assistance is automatically included with every dealer service, and valid for 12 months - it does not matter how the service was booked, via an MB Service Care Plan or not (unless they have changed it very recently, which I don't believe they did).

 

[HelenT]

So here’s the outcome….
“Symptom
WARNLITE
Comments
Customer reports EML light and ESPlights on and lack of engine power. Only EML light on during attendance.
Engine started but run uneven. Noticable smell of engine crankcase fumes. C/o Xentry diagnostic test. Fault code in ME module.
P220101 The NOx sensor 1 has a malfunction. There is a general electrical fault.
P227900 A leak was detected in the intake system.
P061A28 The torque control of the control unit has a malfunction. The signal offset is outside the permissible range.
Process fault codes. Throttle valve guided test ok.
Engine visual check for induction system leaks ok except for engine dip stick not fully home therefore no air tight seal. Fit correctly.
Customer reports EML light has been on for a while and has been told the fault is an exhaust sensor. Engine now runs smoothly.
Erase fault codes and recheck. All clear.
Vehicle is book in with local MB Brooklands for due service.”

Not totally convinced re the replacement of the dipstick correcting the problem, as I know for sure that the dipstick has been correctly placed previously and the EML light was still coming on and misfiring was the symptom, which has been like this since last B service but only intermittently.

Anyway, I queried the reason for the ESP warning coming on, the RAC mechanic said that the dipstick not being in properly could be enough to cause this to come on also

I had a bit of a run out in it and it does now seem to be running fine again

 

[BlackC55]

It needs a NOX sensor.

 

[HelenT]

It needs a NOX sensor.

Ok, thanks BlackC55

 

[BlackC55]

You may need something else for the ESP issue btw.

 

[HelenT]

I’m back, with the same problem. It has just been serviced and brooklands were unable to find anything untoward. All faults were cleared. 2 days later I drove onto a roundabout and it went into ‘limp mode’
I’m getting very concerned and disappointed that after 4 different diagnostic runs nothing tangible has been found. This kind of thing could be potentially very dangerous. I drive the car using and relying on its capability, as in I could possibly have someone plough into the side of me in an instant like that. I think it’s really poor that the issue cannot be pinpointed. Should I now take it back to brooklands for further investigations?

 

[BlackC55]

Is that engine limp mode?

 

[HelenT]

Is that engine limp mode?

Yes, when it drops speed and will only go at 10 miles ph, in a strange kind of surging manor.