GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Door Lock/Indicator Schematics

1

Did you review the Keyless Entry System Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Doors

2

Operate the door locks. Note which locks operate and which locks do not operate from both the door switch and the remote keyless entry transmitter.

Does the door lock function operate normally?

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

Go to Step 3

3

Is the LOCK function inoperative from the door switch and the transmitter?

Go to Step 10

Go to Step 4

4

Is the UNLOCK function operative on the driver's door only from the door switch and the transmitter?

Go to Step 11

Go to Step 5

5

Is the LOCK function inoperative from the transmitter?

Go to Step 12

Go to Step 6

6

Is the UNLOCK function operative on the driver's door only from the transmitter?

Go to Step 13

Go to Step 7

7

Is the UNLOCK function inoperative on the driver's door lock from the door switch and operative on the driver's door lock from the transmitter?

Go to Step 14

Go to Step 8

8

Is the LOCK function inoperative on the driver's door only from the door switch and the UNLOCK function inoperative from the transmitter?

Go to Step 15

Go to Step 9

9

Is the UNLOCK function inoperative on the driver's door only from the door switch and all functions inoperative from the transmitter?

Go to Step 16

Go to Step 19

10

  1. Disconnect the remote control door lock receiver.
  2. Remove the door LOCK relay.
  3. Test for an open condition in the PNK wire between terminal 3 of the door LOCK relay and terminal R of the remote control door lock receiver. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 17

11

  1. Disconnect the remote control door lock receiver.
  2. Remove the door UNLOCK relay.
  3. Test for an open in the PNK/GRN wire between terminal 3 of the door UNLOCK relay and terminal B of the remote control door lock receiver. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 18

12

Test for an open in the PNK wire between the remote control door lock receiver terminal  15 and S226. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 19

13

Test for an open in the RED/WHT wire between the remote control door lock receiver terminal 14 and S222. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 19

14

Test for an open in the PNK/GRN wire between the remote control door lock receiver terminal 7 and S228. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 19

15

Test for an open in the BLK wire between the remote control door lock receiver terminal 13 and G201. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 19

16

Test for an open in the RED/WHT wire between S221 and S222. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 19

17

Test for an open in the BLK wire between terminal 4 and terminal 5 of the door LOCK relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 20

18

Test for an open in the BLK wire between terminal 4 and terminal 5 of the door UNLOCK relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 20

19

Backprobe the remote control door lock receiver with a digital multimeter to ground. Refer to Symptoms - Doors for normal results.

Are the voltage measurements correct?

Go to Step 3

Go to Step 21

20

Inspect for poor connections at the harness connector of the LOCK relay or the 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 24

Go to Step 22

21

Inspect for poor connections at the harness connector of the remote control door lock receiver. 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 24

Go to Step 23

22

Replace the relay.

Is the repair complete?

Go to Step 24

--

23

Replace the remote control door lock receiver. Refer to Door Control Module Replacement .

Is the repair complete?

Go to Step 24

--

24

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3