The ignition switch on your Mercedes is coded to the vehicle, so you will have to reprogram the system for the computer to recognize it. The switch itself is easy to remove but you must first remove the steering wheel, steering column tube module and the trim around the gauge cluster. Please see our articles on these procedures for additional assistance. Remember before removing the airbag and steering wheel to disconnect the ground cable and wait 30 minutes for the electricity to dissipate from the system.
Applies to:C350 (2007-14), C180 (2007-14), C200 (2007-14), C230 (2007-14), C250 (2007-14), C280 (2007-14), C300 (2007-14), C320 (2007-14)
Time: 2 hours
Tab: $370 Talent: 2
Tools: 2 flathead screwdriver drivers
Parts Required: Ignition switch
Hot Tip: Be sure to disconnect the battery and wait 30 minutes
Performance Gain: Car starts Complementary
Modification: Replace steering wheel with upgraded model
Benz W204 EIS Replacement Procedures:
The switch itself is easy to remove but you must first remove the steering wheel (red arrow) steering column tube module (yellow arrow) and the trim around the gauge cluster (green arrow).Please see my article on these procedures for additional assistance.
Mercedes Benz W204 Steering Wheel Airbag Removal Guide
How to Remove Instrument Cluster for Mercedes Benz W204
Remember before removing the airbag and steering wheel to disconnect the ground cable and wait 30 minutes for the electricity to dissipate from the system.
With everything removed you can get access to the switch module from behind the dash (red arrow),but first you need to remove the trim piece the front (yellow arrow).
While Mercedes sells a special tool for removing the trim piece (red arrow) you can do it with two thin flathead screwdrivers.There are plastic notches on the inside to the trim piece;insert the two screwdriver until they are seated against the notches and then turn the piece counter clockwise.Make sure the screwdriver are seated well so you do not risk scratching the trim piece.
Remove the module by reaching in and pushing down on the module with your left hand (red arrow) while pressing in from the front (yellow arrow) with your right hand.
Slightly turn the unit and press in the tabs on the electrical connections (yellow arrows) and separate the connections from the module.
If you have an automatic transmission you will need to remove the lock out cable.Turn the unit so you have access to the cable on the top.Squeeze in the two clips (red arrows) and slide the cable forward (yellow arrow)
You can now slide the lock out tab up and out from the ignition module (red arrow)
Installation of the new unit is the reverse of removal.Remember you will need to have the vehicle programmed to accept access to the new EIS (ignition switch module).
Done!