Operation CHARM: Car repair manuals for everyone.

Drive Signal From A/T Gear Selector





When the selector lever on a car with automatic transmission is moved to a position other than P or N, battery positive voltage is supplied to pin 42 of the Motronic control module. The control module is then programmed for automatic transmission and opens the idle air control valve a little more to compensate for the increase in load.

Pin 42 is not connected on cars with a manual gearbox.