Malfunctions showing randomly

[TomaszC230evo]

Hi, i have bought a 2003 c230 sportcoupe evo automatic and i am having some electric problems. I got the battery check / load check (around 13.7volts engine running), battery seems perfectly fine.

I get a radio reset and then "Battery/Alternator Malfunction" and "Light Sensor Malfunction". Sometimes the trip computer shows "Abs not available" and "Esp not available". If i stop the car, switch off the engine, then switch it back on, the messages dissapear.

Complained back to the trader, but they didn't seem to be able to reproduce the error, funny!
I bought the car on the 30th august, drove the whole week to work, got the message every day! Finally when i picked the car up today, i didn't even manage to do a 100yards and got the "battery/alt" message!!!
He held the car since the 9th sept, had a car electrician to a look at the car for couple of days, but "could find anything".

Any advice?

 

[evdok]

Me thinks it sounds like the alternator!

 

[alibally]

Is it a 271 or a 111 engine?

 

[zerocool]

alternator regulator,there is a bulletin regarding water ingress damage depending on which engine though

 

[TomaszC230evo]

Hi guys, i have the 1.8 compressor engine (192hp).

 

[axesrus]

I had the same problem on a clk230..it should be reading 14.2v when engine running..its something to do with 3 things on the back of the alternator...when 2 pack up..it works on one only..and then finally gives up charging....I got mine refurbed...and hey presto...it went back to 14.2v charge with engine running

 

[TomaszC230evo]

all fixed...

Hi guys, just to say thanks for all your feedback and let you or anyone else interested in this;

as it appeared when i requested him to take the car to the Greenoaks in Ascot for a diagnosis, the previous owner had the car with them already, and guess what? yes, alternator needed replacement; the trader took the car back replaced the part and got the car back... just needed to take a peak into the owner's manual to reset the sunroof...

thanks again!

 

[Dieselman]

I had the same problem on a clk230..it should be reading 14.2v when engine running..its something to do with 3 things on the back of the alternator...when 2 pack up..it works on one only..and then finally gives up charging....I got mine refurbed...and hey presto...it went back to 14.2v charge with engine running

The diodes.

 

[pkripper]

Hi, I have the exact same fault, an independent Merc place said it was initially the battery and the alternator as the battery had been overcharged at some point. But when the guy drove the car and saw the faults mentioned (Light Sensor, ABS,ESP, battery/alt) he said it might be an iginition problem and didnt want to change the alternator if it is not faulty.

Is it a safe bet to go ahead and change the alternator? My car is a C200k sport coupe evo on an 03 plate.

 

[smiddyboy1]

Hi, I have the exact same fault, an independent Merc place said it was initially the battery and the alternator as the battery had been overcharged at some point. But when the guy drove the car and saw the faults mentioned (Light Sensor, ABS,ESP, battery/alt) he said it might be an iginition problem and didnt want to change the alternator if it is not faulty.

Is it a safe bet to go ahead and change the alternator? My car is a C200k sport coupe evo on an 03 plate.

Alternator & Battery? you dont have the luck with you - Girlfriends car had the same, initialy the battery during the cold weather when alternator seemed fine (14.2 volts when running) then decided this week to give up.

Light sensor, ABS, ESP, BAS etc are all common with voltage drops - when the battery / alternator is on their last legs... especially the light sensor.

Dont know so much about the ignition problem, but for £5 you can pop into maplin electronic and buy a multimeter and check the voltage, 12volts car not running and 14.2 volts (ish) when running, and decide from there which way forward.

BTW: Car is also a C200K, around £470 for the alternator and £110 for the battery.