sjcb

Thanks for your help in advance. appreciated, have to start with the back story to give you context so apologies for the long post.

I have a 2003 E500 since I purchased it I have had an issue with the front fan module. according to diag the AC keeps requesting the fan to go 100% , even without AC on. it stays on 100% for most of the time but not all the time. An auto electrician recommend I change the controller in dash , which did not work, then the fan module which did not fix it so have lived with the issue for a year or so. the car has also had random messages on dash regarding ESP and SBC occasionally however just go away randomly or with a clear on a scanner.

A few days ago I was driving and the car kind of went into a limp mode - similar to driving in winter mode, and the dash lit up with all sorts of ESP and other issues issues. when I pulled over and put the car in park, it would not let me put it into drive again. I turned the car off and back on and was able to drive home and scanned the car. (See PDF of scan)

So I did some further investigation reading forums and decided to pull out the ECU and the front SAM.fuse module and found they are a different part number to what was original in that model or the later ones that were compatible with that model. (see pics) , i checked both items and the wiring and there is no evidence of corrosion or water

Original ECU Number - A 113 153 10 91 - The one in my car = A113 153 34 79
Original SAM/fuse front - A 211 545 29 01 - the one in my car = A 211 545 39 01

My questions.

1. do both these items need to be programmed to my VIN. I am assuming that some programming was done as the car has been running for over 12 months with only the fan issue
2. can these 2 devices still be programmed without matching part numbers
3. would a scan via star diags pick up that these are the incorrect devices?

I feel having the incorrect part numbers may be contributing to some of the issues?

also the car was garaged for most of the last 12 months, however been outside of the last 2 months and we have had a fair amount of rain, so I have also read that water may also have contributed to the recent issue (limp mode)

Thanks again

CaliBenzDriver

You've got a lot of issues all mixed together (ECU, SAM, FAN, AC, TCU,..., misc P/N#) so it's hard to know where to stand.
The car was working for over a year and now it got into a limp-mode just the other day.

Can you deal with just that item as top of your list?
Your report has too many code listed for a running car...: clear and retest to get a useful report.

Don't discount a good battery voltage is essential to prevent basic faults. Charge then disconnect battery to reboot the whole car then scan again while providing DC power (engine or charger).

sjcb

Thanks @CaliBenzDriver will check battery voltage. both batteries were replaced a year ago. have cleared the codes and only have 1 left and need to take it for a longer duration road test.