GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Column/Ignition Lock Schematics

1

Verify the fault is present.

Does the system operate normally?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 2

2

Does the automatic transaxle shift lever operate normally?

Go to Step 3

Go to Symptoms - Automatic Transmission Shift Lock Control in Shift Lock Control

3

  1. Turn OFF the ignition.
  2. Disconnect the ignition lock solenoid.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the battery positive voltage and ground circuits of the ignition lock solenoid.
  5. Cycle the gear shift from Park to Drive.

Does the test lamp turn ON and OFF with each cycle?

Go to Step 10

Go to Step 4

4

Does the test lamp remain illuminated with each cycle?

Go to Step 7

Go to Step 5

5

Connect a test lamp between the ground circuit of the ignition lock solenoid and B+ voltage?

Does the test lamp illuminate?

Go to Step 6

Go to Step 8

6

Test the control circuit of the ignition lock solenoid for an open or short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 13

Go to Step 9

7

Test the control circuit of the ignition lock solenoid for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find correct the condition?

Go to Step 13

Go to Step 9

8

Repair the open in the ground circuit of the ignition lock solenoid. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 13

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9

Inspect for poor connections at the automatic transmission shift lock actuator. 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 13

Go to Step 11

10

Inspect for poor connections at the ignition lock 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 13

Go to Step 12

11

Replace the automatic transmission shift lock actuator. Refer to Transmission Control Replacement .

Did you complete the replacement?

Go to Step 13

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12

Replace the ignition lock solenoid. Refer to Park Pawl Actuator Replacement .

Did you complete the replacement?

Go to Step 13

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13

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2