Operation CHARM: Car repair manuals for everyone.

Shift Mode Selector System Performance Test

Connect Scan tool, ignition On/engine Off. Select general information from TCM menu. (Saturn Scan Tool referenced. Check with your scan tool manufacturer for compatibility)

- Scan tool should indicate position of switch.


- Tool display should change when going from Perf to Norm modes.


- The PCM supplies 12 volts to terminal J3E3 (Circuit 1224B). When Perf is selected, the switch will ground circuit 1224B.


- If the Scan tool always reads Perf. regardless of switch position, check for a grounded circuit 1224B. If switch always indicate Norm, check for an open in circuit 1224B