MbNeedshelp

The ECU in my beautiful 2001 S500 was stolen. I have another 2001 s500 in bad shape, that I removed the ecu and what I thought is the immobilizer (where the key fits in and turns) and used the key that went with it, swapped it all out to try and start nicer car that had the ECU stolen and the key turns, but none of the normal lights come on in the instrument cluster and car wont start... What am I missing? I was told swapping all three parts (Key "trasnsponder", immobilizer and ecu as a set) would start my other car. Please help, my bad S500 basically is a parts car being it has so many problems, but it starts and drives.

Please Help.

tusabes

You need to change the shifter too from the donor car

Ecu , key , shifter , and ignition switch must all be swapped as a matched set

MbNeedshelp

Thank you so much for responding. Can you instruct me in where and how to change out the shifter ?

MbNeedshelp

Do you mean the actual shifter, where you put in gear, or the steering column module ?

tusabes

The actual shifter box in the center console

There's tons of YouTube videos how to change it

MbNeedshelp

I ended up taking the car the dealer. I was told by a MB shop they tried that and as they put it "it didn't turn so well" Thank you for your help.

MbNeedshelp

I had to purchase a new ecu and now the dealer can not get the ignition to power up. they are telling me that it keeps blowing fuses in the fwd and rear fuse boxes. they also said it seems the car has water intrusion which is why the fuses keep blowing. now they are telling me the key will not even turn , which it was when i took it there. please anyone help. dont know what to do now

MbNeedshelp

I initially installed an ecu , key switch with matching key from a parts car i have but it would not have any action in the instrument cluster. the cluster would come on when i opened the car so I'm very confused !

tusabes

If it's a water damaged car it will likely never function right unless you get all SAM and wiring harnesses From a good donor car

Jack_88

What made them suspect water intrusion? Was there damp or visible water damage? Germans love putting modules down low, so a lot is susceptible to pooling water.

MbNeedshelp

I inspected the car carefully and found no evidence of water, and one thing the dealer said puzzled me, the key always turned and now they are telling me the key will not turn ? I don't want think they are trying to rip me off but dang there's jut too many issues all of a sudden !

Jack_88

I had a Chrysler dealer sabotage my car and run me about $2000 by the time the dust settled. I couldn't prove it, they'd have just said I caused the damage I found(screwdriver shaped hole in the motor side of the radiator.) So, I would say at least some suspicion is healthy unless you know the dealer well. I've also heard of dealers breaking things on accident and saying it was a preexisting condition to try to dodge liability.

MbNeedshelp

Seems as though the car has been in a flood ? I have not seen it since the dealer gave me the bad news. I asked them to stop all work and asked them to push it out so I could have it towed it home where I have a "donor" car waiting to be cannibalized.

tusabes

the car was not driven in a flood ,but a simple rainfall can cause the interior electronics to get flooded due to a defect

See the First post here , it's a very common problem and was the subject of a class action lawsuit but the time to file a claim is now over
https://mbworld.org/forums/s-class-w...ins-clean.html

MbNeedshelp

Thank you so much for the heads up. Can I use a the good dry units from a donor car to replace the wet ones without any worries abt VIN # compatibility uses ?

tusabes

Yes you can as long as they are the same part numbers

You should be using every part from the donor car - ecu key shifter ignition switch , front and rear SAMs and wiring harness running along passenger floor

They are likely all damaged in the water damaged car and everything needs to be swapped over