GM Service Manual Online
For 1990-2009 cars only

Diagnostic Aids

Central Door Lock and Deadbolt functions are controlled by the rear integration module (RIM), the individual door modules and lock actuators, the driver door key lock cylinder, which is mounted in the driver door, and the key cylinder lock switch, which is contained within the driver door lock actuator. For more information on these components and features, refer to Power Door Latch Description and Operation .

Test Description

The following numbers are corresponding to the steps in the diagnostic table.

  1. This step verifies that the keyless entry remote transmitter is functional for the test procedures that follow in steps 7 and 8. The remote transmitter must be used in place of the driver door key cylinder when it is the driver door deadbolt motor being tested in step 8.

  1. This step determines if the deadbolt motor has failed.

    If it is a passenger door deadbolt being tested in this step, either the driver door key cylinder, or the keyless entry remote transmitter may be used to activate the deadbolt. However, if it is the driver door deadbolt being tested in this step, the driver door key cylinder cannot be used to activate the deadbolt because the lock actuator connector containing the key cylinder input circuit has been disconnected in step 7.

    Care must be taken when observing the test lamp and attempting to activate the deadbolt motor from either the remote transmitter, or the driver door key cylinder. If you are using the remote transmitter, press the transmitter Lock button twice within 3 seconds; the test lamp should flash once. If you are using the driver door key cylinder, either turn the key to the lock position and hold it there for 3 seconds or longer, or, turn it to the lock position twice within 3 seconds; the test lamp should flash once. Repeating either of these activations, however, will not produce another flash of the test lamp until the door has been commanded to undeadbolt. For either method of activation, remember that the door must be commanded to undeadbolt between each deadbolt command in order for the test to be accurate. Failure to follow these guidelines may result in misdiagnosis and the unnecessary replacement of parts.

  2. This step determines if it is the door module or a deadbolt motor control circuit that has failed.

Step

Action

Yes

No

Schematic Reference: Door Lock/Indicator Schematics

Connector End View Reference: Vehicle Access Connector End Views

DEFINITION: A door lock does not deadbolt, or, none of the door locks will deadbolt. This test is used when only a deadbolt function of the door lock system is inoperative and 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

Review the Central Door Lock and Deadbolt section of the Power Door Locks Description and Operation in order to verify that the Power Door Locks Inoperative - Deadbolt complaint is present. Refer to Power Door Locks Description and Operation .

Does the Central Door Lock and Deadbolt system operate as described in the Description and Operation?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Install a scan tool.
  2. With a scan tool, observe the Door Cylinder Switch parameter in the driver door module (DDM) data list.
  3. Insert the door key into the driver door lock cylinder, turn it to the Lock position and hold it for 3 seconds.

Does the Key Cylinder Switch parameters change from Idle to the appropriate state?

Go to Step 4

Go to Step 5

4

Verify that the door locks can be operated from the keyless entry remote transmitter.

Do the door locks operate when using the remote transmitter?

Go to Step 7

Go to Keyless Entry System Inoperative

5

  1. Turn OFF the ignition switch.
  2. Disconnect the harness connector from the driver door lock actuator.
  3. Turn ON the ignition switch, with the engine OFF.
  4. Connect a 3-amp fused jumper wire between the harness connector key cylinder lock switch signal circuit and the key cylinder lock switch ground circuit.
  5. With the scan tool, observe the Door Cylinder Switch parameter.

Does the Key Cylinder Switch parameters change from Idle to the appropriate state?

Go to Step 13

Go to Step 6

6

  1. Connect a 3-amp fused jumper wire to the position between the key cylinder lock switch signal circuit and a good ground.
  2. With the scan tool, observe the Door Cylinder Switch parameter.

Does the Key Cylinder Switch parameters change from Idle to the appropriate state?

Go to Step 10

Go to Step 9

7

  1. Turn OFF the ignition switch.
  2. Disconnect the harness connector from the door lock actuator associated with the inoperative deadbolt motor.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the deadbolt motor control circuit of the harness connector and a good ground.

Does the test lamp illuminate?

Go to Step 11

Go to Step 8

8

  1. Make sure the door associated with the inoperative deadbolt motor locks and unlocks properly.
  2. Make sure the test lamp is still connected between the deadbolt motor control circuit of the harness connector and a good ground.
  3. If the door being tested is the driver door, attempt to deadbolt the door by pressing the Lock button on the keyless entry remote transmitter twice within 3 seconds.
  4. If the door being tested is one of the passenger doors, attempt to deadbolt the door by using either the remote transmitter, or the driver door key cylinder.

Did the test lamp flash once?

Go to Step 14

Go to Step 12

9

Inspect the door lock key ajar switch signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 20

Go to Step 15

10

Inspect the door lock key ajar switch ground circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 20

Go to Step 15

11

Inspect the driver door lock actuator deadbolt control circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 20

Go to Step 16

12

Inspect the driver door lock actuator deadbolt control circuit for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 20

Go to Step 16

13

Inspect for poor connections at the harness connector of the driver 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 20

Go to Step 17

14

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

Did you find and correct the condition?

Go to Step 20

Go to Step 18

15

Check for poor connections at the harness connector of the DDM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 20

Go to Step 19

16

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 20

Go to Step 19

17

Replace the driver door lock actuator. Refer to Front Side Door Lock Actuator Replacement .

Did you complete the replacement?

Go to Step 20

--

18

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

Did you complete the replacement?

Go to Step 20

--

19

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

Did you complete the replacement?

Go to Step 20

--

20

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2