If the key and the EIS don’t match up, “Turn and Start” is deactivated.
Three control units (EIS, ESL and ECU) must all agree the key is correct before the “Turn and Start” function is authorized. Your key has a sequential code, unique to your vehicle, and when inserted into the ignition, your car runs a series of tests, to make sure it’s the right key. Faulty Mercedes EIS ESL Key Replacement Electronic Ignition Switch Replacementĭo you have a Faulty Mercedes EIS ESL? The Mercedes EIS ESL Electronic Ignition Switch and Electronic Steering Lock system exists to make sure your car isn’t stolen.
