For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
1 | Did you review the Automatic Transmission Shift Lock Control Circuit Description and the Automatic Transmission Shift Lock Control Description ? | Go to Step 2 | Go to Automatic Transmission Shift Lock Control System Check
2 |

1. Turn the ignition switch to the ON position.
2. Depress the brake pedal.
3. Attempt to move the manual selector from the P position.

Can you move the manual selector from the P position?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3 |

1. Disconnect the shift lock relay.
2. Turn the ignition switch to the ON position.
3. Depress the brake pedal.
4. Probe the shift lock relay connector with a test lamp from cavity 3 to ground.

Does the test lamp light?

Go to Step 9

Go to Step 4

4 |

1. Backprobe the stoplamp switch connector with a test lamp from cavity 3 to ground.
2. Press and hold the brake pedal.

Does the test lamp light?

Go to Step 5

Go to Step 6

5 | Repair the open in the GRN/WHT wire between the stoplamp switch and the shift lock relay. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 24 | --
6 | Backprobe the stoplamp switch connector with a test lamp from cavity 1 to ground. Does the test lamp light? | Go to Step 8 | Go to Step 7
7 | Repair the open in the GRN wire between the stoplamp switch and S241. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 24 | --
8 | Adjust or replace the stoplamp switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes. Is the repair complete? | Go to Step 24 | --
9 | Probe the shift lock relay connector with a test lamp from cavity 4 to B+. Does the test lamp light? | Go to Step 11 | Go to Step 10
10 | Repair the open in the BLK wire between the shift lock relay and G105. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 24 | --
11 | Probe the shift lock relay connector with a test lamp from cavity 2 to ground. Does the test lamp light? | Go to Step 17 | Go to Step 12
12 | Backprobe the transmission range switch connector with a test lamp from cavity 7 to ground. Does the test lamp light? | Go to Step 13 | Go to Step 14
13 | Repair the open in the ORN/GRN wire between the transmission range switch and the shift lock relay. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 24 | --
14 | Backprobe the transmission range switch connector with a test lamp from cavity 6 to ground. Does the test lamp light? | Go to Step 16 | Go to Step 15
15 | Repair the open in the YEL wire between the transmission range switch and S211. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 24 | --
16 | Replace the transmission range switch. Refer to Transmission Range Switch Replacement in Automatic Transmission. Is the repair complete? | Go to Step 24 | --
17 |

1. Connect the shift lock relay.
2. Backprobe the shift lock relay connector with a test lamp from cavity 1 to ground.
3. Press and hold the brake pedal.

Does the test lamp light?

Go to Step 19

Go to Step 18

18 | Replace the shift lock relay. Is the repair complete? | Go to Step 24 | --
19 |

1. Disconnect the shift lock relay and the shift lock solenoid connectors.
2. Test for continuity using a J 39200 DMM from the shift lock relay connector cavity 1 to the shift lock solenoid connector cavity 3.

Is continuity present?

Go to Step 21

Go to Step 20

20 | Repair the open in the BLU/GRN wire between the shift lock relay and the shift lock solenoid. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 24 | --
21 | Connect a test lamp from the shift lock solenoid connector cavity 6 to B+. Does the test lamp light? | Go to Step 23 | Go to Step 22
22 | Repair the open in the BLK ground wire between the shift lock solenoid and G200. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 24 | --
23 | Replace the shift lock solenoid. Refer to Brake Transmission Shift Interlock Solenoid Replacement in Automatic Transmission. Is the repair complete? | Go to Step 24 | --
24 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3