Test Description

WARNING: This page is about a different car, the 2002 GMC Cab & Chassis Sierra and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The numbers listed below refer to step numbers in the diagnostic procedure:

5

By disconnecting the TR switch, the ground path of all TR switch circuits would be removed and the PCM would recognize all circuits as open. The scan tool will display "HI" for all range signals.

6

This step tests TR switch wiring for an open or the lack of the signal voltage from the PCM.

7

This step tests TR switch wiring and the PCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal "A" should change to "LOW".

8

This step tests TR switch wiring and the PCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal "B" should change to "LOW".

9

This step tests TR switch wiring and the PCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal "C" should change to "LOW".