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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2003 🢒 Yukon - 4WD 🢒 Body and Accessories 🢒 Theft Deterrent 🢒 Power Door Locks Inoperative

Power Door Locks Inoperative Front Door(s)

Step

Action

Yes

No

Schematic Reference: Door Lock/Indicator Schematics

1

Did you perform the Door Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Door Systems

2

Activate the door lock switches to the lock and unlock positions.

Do the driver and front passenger doors lock and unlock?

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

Go to Step 3

3

Do the door lock switches lock and unlock at least one of the front door lock actuators?

Go to Step 4

Go to Step 9

4
  1. Disconnect the inoperative door lock actuator.
  2. With a test lamp connected to a good ground, probe the door lock actuator lock circuit at the door lock actuator harness connector.
  3. Activate a door lock switch to lock position.

Does the test lamp illuminate?

Go to Step 5

Go to Step 7

5
  1. With a test lamp connected to a good ground, probe the door lock actuator unlock circuit at the door lock actuator harness connector.
  2. Activate a door lock switch to unlock position.

Does the test lamp illuminate?

Go to Step 6

Go to Step 8

6
  1. Connect a test lamp between the door lock actuator lock and unlock circuits at the door lock actuator harness connector.
  2. Activate a door lock switch to both the lock and unlock positions.

Does the test lamp illuminate in both positions?

Go to Step 10

Go to Step 9

7

Test for an open or short to ground in the door lock actuator lock circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 9

8

Test for an open or short to ground in the door lock actuator unlock circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 9

9

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

Did you find and correct the condition?

Go to Step 13

Go to Step 11

10

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

Did you find and correct the condition?

Go to Step 13

Go to Step 12

11

IMPORTANT: Perform the set up procedure for the door module. Refer to Service Programming System (SPS) in Programming.

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

Did you complete the repair?

Go to Step 13

--

12

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

Did you complete the repair?

Go to Step 13

--

13

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Power Door Locks Inoperative Rear Door(s)

Step

Action

Yes

No

Schematic Reference: Door Lock/Indicator Schematics

1

Did you perform the Door Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Door Systems

2

Activate the door lock switches to the lock and unlock positions.

Do both rear passenger doors lock and unlock?

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

Go to Step 3

3

Is there only one door lock actuator that is inoperative?

Go to Step 6

Go to Step 4

4

Are the rear door lock actuators inoperative for both lock and unlock?

Go to Step 8

Go to Step 5

5

Do the rear door lock actuators lock?

Go to Step 15

Go to Step 10

6
  1. Disconnect the inoperative door lock actuator.
  2. With a test lamp connected to a good ground, probe the door lock actuator lock circuit at the door lock actuator harness connector.
  3. Activate a door lock switch to lock position.

Does the test lamp illuminate?

Go to Step 7

Go to Step 25

7
  1. With a test lamp connected to a good ground, probe the door lock actuator unlock circuit at the door lock actuator harness connector.
  2. Activate a door lock switch to unlock position.

Does the test lamp illuminate?

Go to Step 24

Go to Step 26

8
  1. Remove the rear door unlock relay.
  2. Connect a test lamp to battery positive voltage.
  3. Probe the door actuator unlock control circuit cavity in the left IP fuse block.

Does the test lamp illuminate?

Go to Step 21

Go to Step 9

9
  1. Install the rear door unlock relay.
  2. Remove the rear door lock relay.
  3. Connect a test lamp to battery positive voltage.
  4. Probe the door lock actuator lock control circuit cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 20

Go to Step 22

10
  1. Remove the rear door lock relay.
  2. Connect a test lamp to a good ground.
  3. Probe the battery positive voltage circuit (high current) cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 11

Go to Step 22

11

With the test lamp connected to a good ground, probe the lock relay control circuit cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 22

Go to Step 12

12
  1. Connect a test lamp to battery positive voltage.
  2. Probe the lock relay control circuit cavity in the fuse block.
  3. Activate a door lock switch to the lock position.

Does the test lamp illuminate?

Go to Step 13

Go to Step 23

13

With the test lamp connected to battery positive voltage, probe the door lock actuator lock control circuit cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 20

Go to Step 14

14
  1. Remove the rear door unlock relay.
  2. With the test lamp connected to battery positive voltage, probe the unlock relay ground circuit cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 21

Go to Step 22

15
  1. Remove the rear door unlock relay.
  2. Connect a test lamp to a good ground.
  3. Probe the battery positive voltage circuit (high current) cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 16

Go to Step 22

16

With the test lamp connected to a good ground, probe the unlock relay control circuit cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 22

Go to Step 17

17
  1. Connect a test lamp to battery positive voltage.
  2. Probe the unlock relay control circuit cavity in the fuse block.
  3. Activate a door lock switch to the unlock position.

Does the test lamp illuminate?

Go to Step 18

Go to Step 23

18

With the test lamp connected to battery positive voltage, probe the door lock actuator unlock control circuit cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 21

Go to Step 19

19
  1. Remove the rear door lock relay.
  2. With the test lamp connected to battery positive voltage, probe the lock relay ground circuit cavity in the fuse block.

Does the test lamp illuminate?

Go to Step 20

Go to Step 22

20

Inspect for poor connections at the rear door lock relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 32

Go to Step 27

21

Inspect for poor connections at the rear door unlock relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 32

Go to Step 28

22

Inspect for poor connections at the left IP fuse block. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 32

Go to Step 29

23

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 32

Go to Step 30

24

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

Did you find and correct the condition?

Go to Step 32

Go to Step 31

25

Repair the open the door lock actuator lock circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 32

--

26

Repair the open in the door lock actuator unlock circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 32

--

27

Replace the rear door lock relay.

Did you complete the repair?

Go to Step 32

--

28

Replace the rear door unlock relay.

Did you complete the repair?

Go to Step 32

--

29

Replace the left IP fuse block.

Did you complete the repair?

Go to Step 32

--

30

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the repair?

Go to Step 32

--

31

Replace the appropriate rear door lock actuator. Refer to Rear Side Door Lock Actuator Replacement .

Did you complete the repair?

Go to Step 32

--

32

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2