Circuit Description
When the transmission lever is in the P (Park) position and the brake pedal at rest, voltage is supplied from the ALT fuse through the PNK/BLK (39) wire to the brake switch. It is also supplied from the switch through the PPL (420) wire to the brake/transmission shift interlock relay contacts and from the TURN-B/U fuse through the DK BLU (75) wire to the backup light switch. Voltage is also supplied from the switch through the PPL (1627) wire to the brake/transmission shift interlock relay coil. Voltage to the brake/transmission shift interlock solenoid is through the DK GRN/WHT (1135) wire. The shift interlock solenoid can be overridden manually by setting the parking brake, placing the ignition switch in the OFF position, and moving the selector lever to the N (Neutral) position. The vehicle can then be started. Relay coil ground is through the BLK (150) wire at the instrument panel ground.
When the brake pedal is depressed, the TCC brake switch contacts open, interrupting the voltage supply to the brake/transmission shift interlock relay. The brake/transmission shift interlock solenoid collapses, allowing the transmission shift lever to be moved from the P (Park) position. When the transmission shift lever is not in the P (Park) position and the brake pedal is not at rest, voltage supply to the relay is interrupted. Also, the brake/ transmission shift interlock solenoid coil collapses, allowing the shift lever to be moved normally between R (Reverse) and D (Drive).
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Is the test lamp ON? | -- | Go to Step 3 | Go to Step 7 |
2 | Connect a test lamp from the PPL (1627) wire at the backup light switch connector to the ground. Is the test lamp ON? | -- | Go to Step 9 | Go to Step 10 |
3 | Connect a self-powered test lamp from the BLK (150) wire at the brake/transmission shift interlock relay connector to the ground. Is the test lamp ON? | -- | Go to Step 4 | Go to Step 11 |
4 | Connect a test lamp between the DK GRN (1630) wire at the brake/transmission shift interlock solenoid connector and the ground. Is the test lamp ON? | -- | Go to Step 12 | Go to Step 5 |
5 | Connect a test lamp between the DK GRN/WHT (1135) wire at the brake/transmission shift interlock solenoid connector and the ground. Is the test lamp ON? | -- | Go to Step 6 | Go to Step 13 |
6 | Connect a test lamp between the DK GRN/WHT (1135) wire and the BLK (150) at the brake/transmission shift interlock solenoid connector and the ground. Is the test lamp ON? | -- | Go to Step 14 | Go to Step 15 |
7 | Check the backup light switch adjustment. Is the adjustment correct? | -- | Go to Step 2 | Go to Step 8 |
8 | Adjust the backup light switch adjustment. Is the repair complete? | -- | Go to Step 1 | -- |
9 | Locate and repair the open in the PPL (1627) wire between the backup light switch connector and the brake/transmission shift interlock relay connector. Is the repair complete? | -- | System OK | -- |
10 | Replace the backup light switch or repair the open in the BLU (75) wire. Is the repair complete? | -- | System OK | -- |
11 | Locate and repair the open in the BLK (150) wire between the brake/transmission shift interlock relay connector and the splice S299 and I/P ground G202. Is the repair complete? | -- | System OK | -- |
12 | Replace the brake/transmission shift interlock relay. Is the repair complete? | -- | System OK | -- |
13 | Locate and repair the open in the DK GRN/WHT (1135) wire between the brake/transmission shift interlock solenoid connector and the brake/transmission shift interlock relay connector. Is the repair complete? | -- | System OK | -- |
14 | Replace the brake/transmission shift interlock solenoid. Is the repair complete? | -- | System OK | -- |
15 | Locate and repair the open in the BLK (150) wire between the brake/transmission shift interlock solenoid connector and the splice S299. Is the repair complete? | -- | System OK | -- |
