Error codes - W203

[zone1london]

Hi,

I picked up a bargain, but I've just found some error codes.

Would appreciate some advise as I'm new to Mercedes. I took it to an independent so called specialist the day after I bought it, and they totally ripped me off and gave me a crazy diagnostic without proof of the codes actually existed. They wanted me to spend over £2000 with them...

Any help would be greatly appreciated.

Thanks in advance.

Danny

Fault log report generated by Torque for Android
===============================================

Current Fault Log
------------------
P0102: Mass or Volume Air Flow Circuit Low Input (I'm replacing the MAF)
P0620: Generator Control Circuit - (Is this the alternator? It was replaced just before I took it, with a supposedly new unit).
P0562: System Voltage Low - (Battery?)
P0172: System too Rich - Bank 1 - (I had a TerraClean run on this car. It spent a long time on the injector sequence of cleaning. Could it be a faulty injector, which could be replaced?

Pending Fault Log
------------------
ECU reports no pending faults

Historic Fault Log
------------------
ECU reports no historic faults
Other discovered fault codes
(possibly pending, current or manufacturer specific)
----------------------------------------------------
P2009: Intake Manf Runner Control Circuit Low bank1 a)
P200A: Unknown code - More information may be available on the web
P2062: Reductant Supply Control Circuit/Open
P2029: Fuel Fired Heater Disabled
P2027: EVAP Fuel Vapor Temperature Sensor Circuit High Voltage

 

[AndyPCD]

Are you actually having any problems with the car. Orvwas the fault code read just for peace of mind.

 

[derekpayne]

What I would do is clear all the faults as it sounds like repairs may have been carried out without the memory being cleared, then drive the car for sometime and see what codes appear if any then tackle any codes then

 

[zone1london]

Are you actually having any problems with the car. Orvwas the fault code read just for peace of mind.

Hi,

Apart from some questionable fuel consumption, no, I'm not having any major noticeable problems. But, if I floor the accelerator, there is a long lag of nothing happening. This is noticeably so from a standing start which I did as a test. It pulls strongly from a gradual but heavy start. I'm assuming this is mass air flow or throttle valve related? If not, accelerator potentiometer? The vast majority of the driving that I've done is on B roads and in the city. I don't have a previous reference point for this model of car.

I forgot to mention, the alternator was replaced just before I picked it up. I slammed on the brakes once, and I think the rear brakes locked up. I've read in various places that the ESP / sensors can sometimes be fried if diconnecting the battery in the improper manner. I'll need to get a Star Diagnostic done when I'm back, as this could be a deal breaker. I'd like to keep the car, but ESP / ABS replacements start getting very expensive. The brake fluid level appears to be slightly over the MAX limit, but I had the front pads and discs were replaced. Correct me if I'm wrong, but the wheels should not lock up either way, right?

I'm doing a 400 mile round trip tomorrow through the course of the week. Maybe I'll clear the codes and see what happens...

I'm thinking the injector on bank 1 could be an issue, as prior to the TerraClean, I had the Check Engine Light come on a couple of times during some city driving. I've not seen it since. I think the fuel consumption is being affected, as I'm averaging about 3 miles lower than I used to on similar runs. It should be the opposite. It does feel a little smoother compared to before. But I'll see how it goes on the long run up the M1 with the replaced mass air flow.

I changed fuel to try out the Shell V Power, I haven't noticed anything significant, but then, I've not had a chance to take it for a good motorway blast. The engine sounds a little different changing to a thinner engine oil. I think it had 5W30, and I don't know when it was last changed. I've put Mobil 1 0W40 in it now. A slight, but consistent ticking noise is coming from somewhere as a result.

The engine idle point when I turn the wheel lock to lock goes down a fair bit and when I tested the A/C and heater at full blast at the same time, the engine did get noticeably lower. So the generator low voltage issues I'm thinking could be the internal regulator? Mercedes told me that they'd probably have to go through the process of elimination by changing one part and another to see if they clear each other out. It's not what I expected to hear, if their Star Diagnostic is supposed to be superior at fault finding. So it's the reason why I've held back on taking it in to them, so far.

Any further hunches or tips to a Mercedes newbie would be appreciated.

Cheers,

Dan