I was wondering if a scan tool will work without an actual key, but with keyless go. I went to get my car scanned, but didnt have an actual key. I use my keyless go and dont carry the key with me (2003 CL600, with keyless go card). The computer said that it could not communicate with the car's computer and I was wondering if it was because I didnt have the key in the ignition. The car was in the "on" position with the keyless go though. Any thoughts?


Thanks,

Jin

You do not need a key in the ignition for the mercedes scan tool to communicate with the vehicle as long as you have pushed the start button and caused the car to be in "key-on" mode.

To add a little bit to MBTECH2003's post I will define the
"Key-on" mode he is describing. I am doing this as it took
two months of owning the vehicle before I figured it out.
With the keyless go in hand, press the start button on
the shifter. Make sure you dont put your foot on the brake,
so it pretty much just starts the electronics of the car, but
does not ignite the engine.