I don't understand how the locking steering wheel could affect the ignition switch mounted on the dash. Steering wheel switches have a mechanical locking device but not those mounted on the dash.

I looked at the Power Distribution Diagram for the ignition switch and see a simple 3 pole, 4 position switch. So I went looking for switches. Found the following switches that appear to be a match for our switches. Note the 7 pins on the switch. Smarts are in the FOB for door locks and ignition switch appears to be dumb and very cheap.



Beck Arnley IGNITION SWITCH mercedes benz SLK320 2004 on eBay!