balamerica

Hi Experts,

My car is having a misfire after it remained parked in a snowstorm. It was running perfectly fine when it was parked. The codes are P0306, P2050-001, P2050-032, P2055-001, P2055-032. I have replaced the spark plugs for #5 and #6 and swapped the coil for #6 with #2, but still getting the same code(s). From the engine noise, it feels as if the complete driver side bank (cylinders 5-8) are misfiring and I think it could be the ECU or a bad connection at the ECU. Can you please help me with the location of the ECU on this car and other expert tips to troubleshoot the issue. I could not locate it in the engine compartment. Thanks a lot for your help !!

marc hanna

Could be a lot of things, I would take it to someone who can read the proprietary codes.

If I were to hazard a guess, based on the age of the vehicle, that it's emissions related, and affects the one bank, that it is a plugged catalytic converter.

balamerica

Thanks a lot, Marc. I have read the above codes using iCarsoft MBII i980 scanner. I checked the temperature at the exhaust outlets (cover) and it was close to 200 degrees F on left (passenger) side (cylinders 1-4) whereas on all of them on the 5-8 cylinder side it was about 130 degrees F only. Though it is a 2006, but It only has 61K miles on it. It was running perfectly fine before it was parked in my driveway on the day of the snowstorm. Seems like the codes P2050 and P2055 are for the REDUCTANT INJECTOR CIRCUIT being high and low. Could it be that the sensor on the catalytic converter got damaged/shorted or something. I was just thinking about cleaning the connectors at the ECU (and may be for the REDUCTANT INJECTOR CIRCUIT). Do you perchance have access to the repair manual to identify the ECU location?
Thanks a lot for the prompt response.

Foondar

I found this difficult to find an answer to, I have searched many posts but no one ever comes out and says 'there it is, right there' Good luck, I'd like to know too.

AsianR350

Is this ECM (ECU) location that you guys are looking for?
https://mbworld.org/forums/r-class-w...werchiped.html

balamerica

Thanks for pointing me to the nice post. I think R350 and R500 are different as I had already removed the air cleaner to get access to the coils, but there was no ECM/ECU under it or on top of the intake manifold. So far i have no success in locating it. I'm planning to put it on ramps and look from underneath if i could find anything next to the firewall as the main cable goes back behind the insulation. I will post pictures of it if i get successful.

Thanks everyone !!

marc hanna

The ECM may be fitted using a bracket somewhere else inside the engine compartment, but it will look the same as the one in the post.

See link for part diagrams and rough orientation:
http://www.mbpartsworld.com/showAsse...ntrol%20module