Some Possible EIS/ ESL failure Symptoms

Possible symptoms of a failed Mercedes-Benz include:

• Key does not turn in the ignition due to failed EIS

• Key doesn’t turn during cold weather

• Key may turn, but the instrument cluster lights don’t turn on

• Unable To Turn The Key, Unable To Start The Car

• Can turn the key but car won’t start

• Mercedes key intermittently works

• Push start button no longer works

Symptoms of Bad CAS Module

• Malfunction message on the iDrive screen

• Key not recognized

• The car will turn over but not start.

• Vehicle Will Not Start  - A defective CAS module that has been damaged from water or due to low or overvoltage will prevent the vehicle from starting. Replacing the CAS module and programming is necessary to fix this problem.

• Mismatched Key - The code in the CAS module may get out of sync with the code stored in the DME / DDE module.