GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

DEFINITION: The lock system does not allow the key to rotate out of the OFF position.

1

Did you review the Ignition Lock System Description and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Steering Wheel and Column

2

Verify that the lock system does not unlock.

Does the lock system operate normally?

System OK

Go to Step 3

3

Inspect for an incorrect, worn, or damaged key.

Is the key incorrect, worn, or damaged?

Go to Step 8

Go to Step 4

4

Inspect for a faulty lock cylinder.

Is the lock cylinder damaged?

Go to Step 9

Go to Step 5

5

Inspect the automatic transmission shift lock control adjustment.

Is the automatic transmission shift lock control adjusted incorrectly?

Go to Step 10

Go to Step 6

6

Inspect the lock module assembly for damage.

Is the lock module assembly damaged?

Go to Step 11

Go to Step 7

7

Inspect the ignition switch assembly for damage.

Is the ignition switch assembly damaged?

Go to Step 12

Go to Step 3

8

Replace the key. Refer to Key and Lock Cylinder Coding in General Information.

Did you complete the repair?

Go to Step 13

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9

Replace the lock cylinder. Refer to Ignition Lock Cylinder Replacement - On Vehicle .

Did you complete the repair?

Go to Step 13

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10

Adjust the automatic transmission shift lock control. Refer to Automatic Transmission Shift Lock Actuator Replacement .

Did you complete the repair?

Go to Step 13

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11

Tighten the lock module assembly. Refer to Fastener Tightening Specifications .

Did you complete the repair?

Go to Step 13

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12

Replace the ignition switch. Refer to Ignition Switch Replacement - On Vehicle .

Did you complete the repair?

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 3