Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

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