Originally Posted by 02MysteryMachine
90% of the time there's just a wire that runs from the headunit to the e-brake wiring. I believe its a blue wire. You just need to trace the wire from the headunit to the ebrake wires n snip it n tap it off....just my two cents
I have the 940xbt also. The e brake wire is green. Also on this model you can not just snip it and ground it out like older models.
I got a quote from FOSS audio for $50 to do it. Not a bad price if you don't know what your doing/risk messing something up.