Transmission Mode Switch: Testing and Inspection

PROGRAM BUTTON
The program button switches one pin at a time to ground. The corresponding output pin is switched to ground in the control unit until another program has been selected or the vehicle is restarted (holding circuit). Check the program button by means of the universal adapter with the control unit connected and ignition switched "ON", (measure between Pin 28 (-) and the specified pins; "0" corresponds to approx. 0 V, "+" corresponds to approx. 12 V).





If the values are not plausible, check ground connection of the program button and repair if necessary, If OK, remove program button, refer to block diagram and switch views and repair if necessary. If OK, check wire and connector, repair if necessary. The holding circuit in the control unit is defective if the current symbol lights in the program button only when the relevant program is depressed.