GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Power Door Systems Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Power Door Systems

2

Verify that the endgate/liftgate lock cylinder switch is inoperative.

Does the endgate/liftgate lock cylinder switch operate normally?

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

Go to Step 3

3

  1. Disconnect the endgate/liftgate lock cylinder switch connector.
  2. Connect a test lamp between the switch terminal D CKT 840 (ORN) and ground.

Does the test lamp light?

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Go to Step 4

Go to Step 6

4

Connect a 3A fused jumper wire between terminal D, CKT 840 (ORN) and terminal A, CKT 195 (LT BLU) of the endgate/liftgate lock cylinder switch connector.

Do the doors LOCK?

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Go to Step 5

Go to Step 7

5

Connect a 3A fused jumper wire between terminal D, CKT 840 (ORN) and terminal B, CKT 194 (WHT) of the endgate/liftgate lock cylinder switch connector.

Do the doors UNLOCK?

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Go to Step 9

Go to Step 8

6

Repair an open in CKT 840 (ORN). Refer to Wiring Repairs in wiring systems.

Is the repair complete?

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Go to Step 10

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7

Repair the open in CKT 195 (LT BLU). Refer to Wiring Repairs in wiring systems.

Is the repair complete?

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Go to Step 10

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8

Repair the open in CKT 194 (WHT). Refer to Wiring Repairs in wiring systems.

Is the repair complete?

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Go to Step 10

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9

Replace the endgate/liftgate lock cylinder switch. Refer to Endgate Lock Cylinder Replacement or Liftgate Lock Cylinder Replacement in body rear end.

Is the repair complete?

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Go to Step 10

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10

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3