Mercedes EIS/EZS Repair specialists - EIS testing 

The Mercedes DAS system mainly works around the EIS (Electronic Ignition Switch) so any malfunction or fault may cause the system to not work. 


The EIS holds vital Key data and links to the ECU and ESL (Electronic Steering Lock) and also acts as a central gateway to other vehicle electrics, Meaning eis and key faults could seem to cause other system faults.


EIS Faults -

  • Not allowing the key to turn
  • Not releasing the ESL (Electronic Steering Lock) when the key is Inserted
  • Intermittent failure of internal components causing intermittent faults
  • Complete failure of internal components
  • DATA corruption causing failure
  • Dirt ingress causing failure
  • Incorrect programming by an incompetent garage/mechanic


Many EIS's can be easily fixed, with replacement parts or a service exchange unit - If a unit cannot be repaired or replaced we can supply a new unit which is fully plug and play requiring no other programming.


Please use the contact form or send us an email -