(W220) Engine Diagnostic light on

[LTD]

Well, I suppose it had to happen some day .......

I got my first warning light on the W220 - the yellow Engine Diagnostic indicator.

Handbook suggests 'fuel system, ignition system, exhaust system problem - consult dealer'

So I'll be phoning the Indy to see if he can look at it tomorrow.

What I have noticed is the following :

• It came on whilst sitting in traffic.
• Noted that the engine temperature had risen from 80C to just under 100C
• Engine temperature dropped when the car had a run on the open road - still pulls like a train and no apparent misfiring.
• Radiator fan does not seem to be operating

Could it be a temp sensor in the cooling system ? Blown fuse ?

It'll go the the Indy tomorrow anyway but does anyone have any ideas to share ?

 

[jaymanek]

could be a thousand things.. get it plugged in and see what it says!

 

[LTD]

could be a thousand things.. get it plugged in and see what it says!

Hopefully it's just one thing wrong !!!!

It's booked in for Tuesday next week so I'll know then once they run the diagnostics.

 

[st4]

Well, I suppose it had to happen some day .......

I got my first warning light on the W220 - the yellow Engine Diagnostic indicator.

Handbook suggests 'fuel system, ignition system, exhaust system problem - consult dealer'

So I'll be phoning the Indy to see if he can look at it tomorrow.

What I have noticed is the following :

• It came on whilst sitting in traffic.
• Noted that the engine temperature had risen from 80C to just under 100C
• Engine temperature dropped when the car had a run on the open road - still pulls like a train and no apparent misfiring.
• Radiator fan does not seem to be operating

Could it be a temp sensor in the cooling system ? Blown fuse ?

It'll go the the Indy tomorrow anyway but does anyone have any ideas to share ?

Money is on thermostat going kaput or a temp sensor and that could knock out the radiator fan. Although if the fan is ****ed then it will overheat.

Although what I really suspect is you've finally managed to break it after 1 year of solid hard abuse of driving it as fast as you possibly could wherever you went.

 

[LTD]

Solved courtesy of IBW and Star.

The light was caused by the Crankshaft Hall Sensor reporting something was not right.

Reset, restarted and retested clear.

Testing drive home in nose to tail traffic - no lights returned.

Big thanks to Ian !!!!!

 

[tonyho8]

Hello,
Last month (September) I purchased a used C200k (2001) which had already done 77000 miles from a private seller. I immediately took it to Halfords Autocentre (UK) for a major service to make sure the car is drivable for the long-term.

Since purchasing the car last month, I've only driven 30 miles, mostly during the weekends to visit my parents in the same town as I don't use the car during the working week.

Yesterday, I drove to a restaurant to have dinner with my parents and the car travelled well as per usual. However, after coming home from dinner, I noticed that the Engine Diagnostic Indicator lamp lit up. There were no driving issues despite the lamp lighting up during the drive.

I checked the driving manual and it explains that it could be an issue with the injection system, ignition system or exhaust system

Can someone recommend what I should do to determine whether there is a major issue? Should do I take it back to Halfords AutoCentre for them to review this issue since they were the ones that carried out the major service last month? Or do you recommend that I take it to a Mercedes-Benz dealer to have this investigated and fixed?

Your feedback and guidance would be much appreciated

Thanks and regards,

Tony

 

[LTD]

I'd head to a decent Indy with STAR diagnostics.

 

[GlenQ]

Hello,
Last month (September) I purchased a used C200k (2001) which had already done 77000 miles from a private seller. I immediately took it to Halfords Autocentre (UK) for a major service to make sure the car is drivable for the long-term.

Since purchasing the car last month, I've only driven 30 miles, mostly during the weekends to visit my parents in the same town as I don't use the car during the working week.

Yesterday, I drove to a restaurant to have dinner with my parents and the car travelled well as per usual. However, after coming home from dinner, I noticed that the Engine Diagnostic Indicator lamp lit up. There were no driving issues despite the lamp lighting up during the drive.

I checked the driving manual and it explains that it could be an issue with the injection system, ignition system or exhaust system

Can someone recommend what I should do to determine whether there is a major issue? Should do I take it back to Halfords AutoCentre for them to review this issue since they were the ones that carried out the major service last month? Or do you recommend that I take it to a Mercedes-Benz dealer to have this investigated and fixed?

Your feedback and guidance would be much appreciated

Thanks and regards,

Tony

Two hijacked threads on two forums, this one with a solution. Take it in to have the fault codes read!!

 

[trapperjohn]

+1 with LTD. It how the mechanic uses the information from STAR to correct the fault. Experience with Mercedes goes a long way to decyphering the codes and replacing the correct parts.
You could end up being Halford's best customer if you are not careful.

 

[tonyho8]

Hi everyone,

Thanks for the previous feedback and advice in addressing the reasons behind why my Engine Diagnostic Indicator/Check Engine Light lit up.

Since then I have driven the car only for 5 miles (to and from my parents place) and yesterday I received my OBD2 reader which I purchased online.
FYI my local MB dealer wanted to charge me 150 UK pounds to investigate the problem whereas other garage mechanics wanted to charge me 45 UK pounds
Hence I felt it was appropriate for me to purchase a OBD2 reader at 40 UK pounds to investigate the matter myself before taking the car to a garage.

I quickly connected the OBD2 reader to my car and it gave me a single DTC code - P0101 "Mass or Volume Air Flow A Circuit Range / Performance"

The OBD2 reader also allowed me to collect and record "live data" (total of 60 frames) whilst the engine was running and the following are the results of 1 out of 60 frames

DTC_CNT = 1
FUELSYS1 = CL_FAULT
FUELSYS2 = N/A
LOAD_PCT (%) = between 18.0 and 23.1
ETC = between 72 and 84
SHRTFT1 (%) = between -5.5 and -1.6
LONGFT1 = 0.0
RPM (/min) = between 740 and 761
VSS (km/h) = 0
SPARKADV = between 14 and 15
IAT = between 27 and 29
MAF (g/s) = 3.42 and 3.74
TP (%) = 4.3
AIR_STAT = no results
O2S_B1S12--B2S----
O2B1S1 (V) = between 0.110 and 0.570
SHRTFTB1S1 (%) = between -0.8 and 0.8
O2B1S2 (V) = 0.455
OBD = EOBD

I have not taken the car back to my nearest garage (Halfords Autocentre) to be fixed ever since I posted my previous message here as I was keen to read the code to investigate the root cause first.
Please note that I took my car to Halfords Autocentre for a typical annual service before the Engine Diagnostic Indicator/Check Engine Light lit up last month. Also, I purchased an additive from Halfords called "Slick 50" for which I asked Halfords Autocentre to add to my car during the annual service.

Before I go back to the same garage next weekend, can anyone on this forum advise me whether the issue I described above is severe based on the data I've provided?
What should I be asking the garage people to look into? and what sort of cost am I expected to pay? This issue appeared after my car underwent the annual service. Is this a matter of the garage people not doing a thorough job?

Your feedback and guidance would be much appreciated

Thanks and regards,

Tony

 

[LTD]

Those numbers will probably be meaningless to all but an experienced mechanic.

As I said before, you should have gone to an Independent with a STAR system. For a little more cash you would have had the benefit of an experienced mechanic and you would probably know the answer to the problem by now.

All your OBD2 reader has done is verified the car's onboard fault detection.

Go to a Mercedes Independent. Get your car fixed properly as it will save you a lot of money and grief in the future.