Hello I have a 2000 Mercedes S-500. I need to replace the transmission control unit. It has water damage. I bought a used on ebay with same part numbers, but I was told it has to be a brand new unit and get programed to my car with mb star. Is that correct?

I was looking into the ktag cloning but not sure if it works on the TCM.

With the used tcm installed the car actually starts up so I know the original module is bad. However I am having other problems such airamatic pump not engaging and park lock on the shifter. Thanks!

 

a Tcu has no effect on starting and does not need programming .

if the car had water damage then other parts are likely damaged such as the Ecu . That does need to be matched to the car (you can only use a used one if you swap the ecu, shifter, key and ignition switch from a donor car)

 

I'm curious how you arrived at the TCM as being the fault - your symptoms suggest other problems and throwing a TCM in this car may not help at all...

 

Classic: Get an S600, have problems, throw parts at it!
SDS!!!!

 

OP has a 2000 S500.

Still no answer as to why he thinks the TCU is responsible for his problems.

 

Hey guys when I put in the orginal tcm the car does not start. It is starting fine with the used one from ebay. I believe it has something to do with the car cannot tell what gear it's in. I got no check engine lights engine computer is fine. Car is running great. I just purchased a brand new battery.

Problems now I'm getting airamatic visit workshop, ESP error, and BAS errors. The rear air bag shocks are completely slammed on the ground now though.. can not drive.. I jumped the air pump relay O and pump does come on. But no change in ride height. Also the shifter lock does not disengage when I press on the brake I have to use the bump on the top method since this car has no release button.

If you guys are certain a used tcm is no problem I'm going to go for mb star 3 or the car soft scanner and start from there.

Also my airbag light is on! Lol

 

carsoft won’t help you , needs sds.

esp and bas always come on when resurrecting a dead car. Simply driving it and turning the steering wheel lock to lock should clear those errors . Your airmatic is faulty because of whatever water damage harmed other components . Airbag light is either water damage or the passenger seat occupancy sensor , buy a passenger seat emulator to rule it out

 

Got the icarsoft scanner today.



Car is still bottomed out in the rear and airmatic pump doesnt want to turn on. TCM seems fine. I'm leaning towards the rear axle level sensor... going to get under the car and check it

 

It is not too unusual for the linkage for the rear axle sensor to fail, usually due to rust.

 

Bingo looks like the rear linkage bar is gone between the leveling sensor and the sway bar. Both sides just have ball joint part bolted to them.

You guys have a part number? I'm looking around. it's a year 2000 Mercedes S500. thanks!