For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: Transmission shift lever does not lock in the park position with the ignition ON and the brake pedal not depressed
1 |

1. Connect a test lamp between the voltage supply circuit at the stoplamp/auto trans shift lock control switch and a good ground.
2. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

--

Go to Step 2

Go to Step 7

2 | Connect a test lamp between the auto trans shift lock solenoid supply voltage circuit at the stoplamp/auto trans shift lock control switch and a good ground. Does the test lamp illuminate? | -- | Go to Step 3 | Go to Step 11
3 | Connect a test lamp between the auto trans shift lock solenoid supply voltage circuit at the auto trans shift lock control solenoid and a good ground. Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 8
4 | Connect a test lamp between the neutral safety switch signal circuit at the auto trans shift lock control solenoid and battery positive voltage (B+). Does the test lamp illuminate? | -- | Go to Step 13 | Go to Step 5
5 | Connect a test lamp between the neutral safety switch signal circuit at the transmission range switch and battery positive voltage (B+). Does the test lamp illuminate? | -- | Go to Step 6 | Go to Step 9
6 | Connect a test lamp between the transmission range switch ground circuit at the transmission range switch connector and battery positive voltage (B+). Does the test lamp illuminate? | -- | Go to Step 15 | Go to Step 10
7 | Repair the open or high resistance in the stoplamp/auto trans shift lock control voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 17 | --
8 | Repair the open or high resistance in the auto trans shift lock solenoid supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 17 | --
9 | Repair the open or high resistance in the auto trans shift lock solenoid neutral safety switch signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 17 | --
10 | Repair the open or high resistance in the transmission range switch ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 17 | --
11 |

1. Inspect for proper stoplamp/auto trans shift lock switch adjustment. Refer to Stop Lamp Switch Adjustment in Hydraulic Brakes.
2. Inspect for poor connections at the stoplamp/auto trans shift lock control switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 12

12 | Replace the stoplamp/auto trans shift lock control switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes. Did you complete the repair? | -- | Go to Step 17 | --
13 | Inspect for poor connections at the auto trans shift lock control solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 14
14 | Replace the auto trans shift lock control solenoid. Refer to Automatic Transmission Shift Lock Control Actuator Replacement - On Vehicle in Steering Wheel and Column-Tilt. Did you complete the repair? | -- | Go to Step 17 | --
15 | Inspect for poor connections at the transmission range switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 16
16 | Replace the transmission range switch. Refer to Park/Neutral Position Switch Replacement Did you complete the repair? | -- | Go to Step 17 | --
17 | Operate the system in order to verify the repair? Did you find and correct the condition? | -- | System OK | Go to Step 1