GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Door Lock/Indicator Schematics

Connector End View Reference: Vehicle Access Connector End Views

DEFINITION: This test assumes that all DTCs have been diagnosed.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Close all of the vehicle doors.
  3. Turn on the ignition switch, with the engine OFF.
  4. Operate the door lock switch to lock and unlock position.

While operating the door lock switch, are DTC U1162 and U1163 set simultaneously?

Go to Step 8

Go to Step 3

3

  1. With a scan tool, observe the Door Lock Switch parameter in the driver door switch assembly (DDSA) data list.
  2. Operate the driver door lock switch to both the Lock and Unlock positions.
  3. With a scan tool, observe the Door Lock Switch parameter in the front passenger door module (PDM) data list.
  4. Operate the front passenger door lock switch to lock and unlock position.

Do the two switch parameters change to Lock and Unlock status?

Go to Step 7

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the inoperative door lock switch signal circuit for a short to ground.
  3. Connect a 3-amp fused jumper between the harness connector of door lock switch lockout signal circuit and ground circuit.
  4. With engine OFF, turn the ignition on.
  5. With the scan tool, observe the appropriate Door Lock Switch parameter.
  6. Turn OFF the ignition switch.
  7. Disconnect the 3-amp jumper at the door lock lockout signal circuit.
  8. Connect a 3-amp fused jumper between the harness connector of door lock switch unlock signal circuit and ground circuit.
  9. With engine OFF, turn the ignition on.
  10. With the scan tool, observe the appropriate Door Lock Switch parameter.

Do the Door Lock Switch parameters change to Lock and Unlock status?

Go to Step 5

Go to Step 6

5

  1. Turn OFF the ignition switch.
  2. Connect a 3-amp fused jumper to the position between of door lock switch lockout signal circuit and the ground circuit of door lock switch harness connector.
  3. With engine OFF, turn the ignition on.
  4. With the scan tool, observe the appropriate Door Lock Switch parameter.

Do the Door Lock Switch parameters change to Unlock status as expected?

Go to Step 9

Go to Step 13

6

Important:: If a power door lock switch signal circuit is found to be shorted to battery voltage, the lock switch may need to be replaced.

Inspect the Lock and Unlock signal circuits of the inoperative door lock switch for opens, shorts to each other, or short to battery. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 18

Go to Step 10

7

Inspect the door lock actuator unlock and lock control circuits of the inoperative rear door lock actuator for an open, short to ground, or short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 18

Go to Step 11

8

Inspect the lock and unlock control circuits of both rear door lock actuators for a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 18

Go to Step 12

9

Inspect for poor connections at the appropriate door lock switch harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 18

Go to Step 14

10

Inspect for poor connections at the appropriate harness connector of, either the PDM, or, if the inoperative lock is the driver door lock, the driver door switch assembly (DDSA). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 18

Go to Step 15

11

Inspect the poor connections at the appropriate door control module harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 18

Go to Step 16

12

Inspect for poor connections at the harness connector of inoperative door lock actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 18

Go to Step 17

13

Locate and repair open circuit or high resistance in appropriate door lock switch ground circuits. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 18

--

14

Replace the appropriate door lock switch. Refer to Door Lock and Side Window Switch Replacement - Driver Side or Door Lock Switch Replacement .

Did you complete the replacement?

Go to Step 18

--

15

Replace the PDM, or replace the DDSA, if the inoperative lock is the driver door lock. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 18

--

16

Replace the door control module. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 18

--

17

Replace the inoperative door lock actuator. Refer to Rear Side Door Latch Replacement .

Did you complete the replacement?

Go to Step 18

--

18

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2