GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

DEFINITION: The endgate lock cylinder switch does not operate. The remote release function on the rear wiper/washer and endgate window release switch does operate correctly.

1

Did you review the release system operation and perform the necessary inspections?

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Go to Step 2

Go to Symptoms

2

Verify that the endgate window release is inoperative with the endgate lock cylinder switch.

Does the endgate window release operate normally?

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

Go to Step 3

3

    • Access the endgate lock cylinder switch.
    • Disconnect the endgate lock cylinder switch connector.
    • Connect a digital multimeter (DMM) from ground to CKT 840 (ORN) cavity D of the endgate lock cylinder switch. Refer to Circuit Testing in wiring systems.

Is battery voltage present?

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Go to Step 4

Go to Step 7

4

  1. Close the lift window if open?
  2. Ensure that the right front door is unlocked.
  3. Momentarily connect a 3A fused jumper wire between terminals C and D of endgate lock cylinder switch connector. Refer to Circuit Testing in wiring systems.

Did the endgate window release actuator operate?

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Go to Step 10

Go to Step 5

5

  1. Disconnect the RH door lock cylinder switch connector.
  2. Connect a DMM from ground to CKT 1221 (BLK/WHT) cavity B of the RH door lock cylinder switch connector. Refer to Circuit Testing in wiring systems.
  3. Activate the endgate lock cylinder switch.

Is battery voltage present?

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Go to Step 6

Go to Step 8

6

  1. Close the lift window
  2. At the RH door lock cylinder switch connect a fused jumper wire from CKT 1221 (WHT/BLK) cavity B to CKT 56 (BLK/WHT) cavity D. Refer to Circuit Testing in wiring systems.
  3. Activate the endgate lock cylinder switch.

Did the endgate window release actuator operate?

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Go to Step 11

Go to Step 9

7

Repair the open or high resistance in CKT 840 (ORN) Refer to Wiring Repairs in wiring systems.

Is the repair complete?

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Go to Step 12

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8

  1. Repair the open or high resistance in CKT 1221 (WHT/BLK) Refer to Wiring Repairs in wiring systems.
  2. Connect the RH door lock cylinder switch connector.
  3. Return the door access panel to normal.

Is the repair complete?

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Go to Step 12

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9

Repair the open or high resistance in CKT 56 (BLK/WHT) Refer to Wiring Repairs in wiring systems.

Is the repair complete?

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Go to Step 12

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10

Replace the endgate lock cylinder switch. Refer to Endgate Lock Cylinder Replacement .

Is the repair complete?

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Go to Step 12

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11

Replace the RH door lock cylinder switch. Refer to Door Lock Cylinder Replacement in doors.

Is the repair complete?

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Go to Step 12

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12

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3