GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

DEFINITION: The ignition lock cylinder will not allow the key to be turned to the LOCK position.

1

Did you review the Steering Wheel and Column Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Steering Wheel and Column

2

Verify that the lock system does not lock.

Does the lock system lock?

System OK

Go to Step 3

3

Rotate the steering wheel and attempt to turn the key to the LOCK position.

Are you able to turn the key to the LOCK position?

System OK

Go to Step 4

4

Does the vehicle have an automatic transmission?

Go to Step 5

Go to Step 7

5

  1. Place the automatic transmission shift lever in Park.
  2. Rotate the steering wheel and attempt to turn the key to the LOCK position.

Are you able to turn the key to the LOCK position?

System OK

Go to Step 6

6

Inspect the automatic transmission park lock cable for binding or damage.

Is the automatic transmission park lock cable binding or damaged?

Go to Step 10

Go to Step 7

7

Inspect the lock cylinder case for damage.

Is the lock cylinder case damaged?

Go to Step 11

Go to Step 8

8

Inspect the lock cylinder for damage.

Is the lock cylinder damaged?

Go to Step 12

Go to Step 9

9

Inspect the ignition switch for damage.

Is the ignition switch damaged?

Go to Step 13

Go to Step 2

10

Replace the automatic transmission park lock cable. Refer to Park Lock Cable Replacement in Shift Lock Control.

Did you complete the repair?

Go to Step 14

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11

Replace the lock cylinder case. Refer to Ignition Lock Cylinder Case Replacement .

Did you complete the repair?

Go to Step 14

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12

Replace the lock cylinder. Refer to Ignition Lock Cylinder Replacement .

Did you complete the repair?

Go to Step 14

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13

Replace the ignition switch. Refer to Ignition and Start Switch Replacement .

Did you complete the repair?

Go to Step 14

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14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2