Start error usually means issues with the immobilizer where it cant read they key info to start the car. With the TCM thats partially correct if its the older Siemens unit which has EGS51 stamped on it - then yes its a straight swap, no programming as long as the part numbers match from the replacement unit.

MB started to use the EGS52 units from about the year 2000 and mainly on the AMG vehicles at the time - this are programmable.

Example of a EGS51 unit - again please make sure part numbers match as these computers are used in many models of MB car - the reason why its important as the diff ratio is pre-programmed into them from factory so if its the wrong part number weird things will happen.

 

Start error usually means issues with the immobilizer where it cant read they key info to start the car. With the TCM thats partially correct if its the older Siemens unit which has EGS51 stamped on it - then yes its a straight swap, no programming as long as the part numbers match from the replacement unit.

MB started to use the EGS52 units from about the year 2000 and mainly on the AMG vehicles at the time - this are programmable.

Example of a EGS51 unit - again please make sure part numbers match as these computers are used in many models of MB car - the reason why its important as the diff ratio is pre-programmed into them from factory so if its the wrong part number weird things will happen.
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Thank you very much for your quick response! As for the error, I too was under the impression that it was an immobilized error. However I was surprised when the MB service advisor told me it was a TCM issue.
I willcheck if it TCM is EGS51 or EGS52. However if it is the latteris it only MB that can program the replaced TCM?

thank you!

 

An independent merc mechanic should be able to do it - just search for one in your area and call to confirm. most good independent workshops have the diagnostic tools to be able to do this.

I'm just weary this MB dealership will just be replacing parts without actually fixing the problem (car wont start). the car will still start with a faulty TCM. A common fault is oil wicks its way up into it from the transmission plug. The car may not shift gears correctly or even go into gear (act like its in neutral), but the motor will still run.

what most people do is take the TCM apart and clean it with electrical contact cleaner and let it dry out and this works 90% of the time, unless there is corrosion etc. the circuit board in the TCM is coated in an epoxy from memory so its protected to some degree.

 

Thank you! Appreciate your advise very much.
Yes, I will inquire around to see if something be can fix the issue.