GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Important: A short to ground will cause an open fuse(s). Before performing this diagnostic procedure, Inspect the fuse(s) for an open.

1

Important: Verify that the valet mode switch on the rear compartment lid release motor is OFF position, the transaxle gear selector is in PARK and that the battery is fully charged and in good condition prior to following this diagnostic chart. Failure to do so may result in misdiagnosis and unnecessary parts replacement.

Operate the trunk release switch for the rear compartment lid release.

Did the rear compartment lid release operate?

--

Go to Step 2

Go to Step 3

2

Activate the trunk release function with the remote function actuator (RFA) keyfob.

Did the rear compartment lid release operate?

--

Go to Step 20

Go to Diagnostic System Check - Remote Keyless Entry in Keyless Entry

3

While operating the trunk release switch on the driver door panel, listen for operation of the rear compartment lid release relay.

Did the relay click?

--

Go to Step 12

Go to Step 4

4

Use a scan tool in order to inspect for body control module (BCM) diagnostic trouble codes (DTCs).

Are BCM DTCs B3267 or B3268 stored Current or in History?

--

Go to Diagnostic System Check - Body Control System in Body Control System

Go to Step 5

5

  1. Select BCM Special Functions, Output Control for the trunk release relay on the scan tool.
  2. Command the trunk release relay open.

Did the rear compartment lid release operate?

--

Go to Step 6

Go to Step 11

6

Use the scan tool in order to observe the BCM input data parameter for the trunk release switch.

Is the trunk release switch status on?

--

Go to Step 8

Go to Step 7

7

  1. Observe the trunk release switch status on the scan tool.
  2. Activate the trunk release switch on the driver door panel.

Did the trunk release switch status change from OFF to ON?

--

Go to Step 25

Go to Step 9

8

  1. Observe the trunk release switch status on the scan tool.
  2. Remove the trunk release switch from the driver door panel.
  3. Disconnect the connector from the trunk release switch.

Did the trunk release switch status change from ON to OFF?

--

Go to Step 22

Go to Step 18

9

  1. Observe the trunk release status on the scan tool.
  2. Remove the trunk release switch from the driver door panel.
  3. Use a fused jumper in order to backprobe CKT 1576 (terminal D) to ground.

Did the trunk release switch status change from OFF to ON?

--

Go to Step 10

Go to Step 19

10

  1. Test CKT 550 for an open or high resistance between the release switch connector terminal A and G301.
  2. Replace the trunk release switch if CKT 550 is functional.

Is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

11

  1. Remove the rear compartment lid release relay from the left instrument panel (IP) wiring harness junction block.
  2. Use a test lamp and J 35616-A connected to B+ in order to probe CKT 85 at the left IP wiring harness junction block cavity.
  3. Select BCM Special Functions, Output Control for the trunk release relay on the J 39200 .
  4. Command the trunk release relay ON.

Did the test lamp illuminate?

--

Go to Step 12

Go to Step 25

12

  1. Replace the trunk release relay with a known good relay.
  2. Retest the operation of the rear compartment lid release.

Did the rear compartment lid release operate?

--

Go to Step 21

Go to Step 13

13

  1. Remove the rear compartment lid release relay from the left IP wiring harness junction block.
  2. Use a test lamp and J 35616-A connected to ground in order to test both cavities for CKT 1040 for the left IP wiring harness junction block.

Did the test lamp illuminate brightly at both cavities?

--

Go to Step 14

Go to Step 24

14

  1. Ensure that the ignition switch is in the OFF position and the engine is not running.
  2. Remove the trunk release relay from the left IP wiring harness junction block.
  3. Use the J 39200 configured for measuring and recording amperage on the 40 Amp D/C scale and J 35616-A .
  4. Connect the negative lead of the J 39200 to the cavity for CKT 56 of the left IP wiring harness junction block.
  5. Momentarily connect the positive lead of the J 39200 to the cavity for the CKT 1040 of the left IP wiring harness junction block.

Was the maximum Amperage measured higher than the value specified?

3.06-3.74 amps

Go to Step 17

Go to Step 15

15

Inspect the measured amperage.

Was the amperage measured lower than the value specified?

3.06-3.74 amps

Go to Step 16

Go to Step 20

16

  1. Inspect CKT 56 and CKT 750 for an open or high resistance.
  2. Replace the rear compartment lid release motor if CKT 56 and CKT 750 are functional.

is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

17

  1. Test CKT 56 for a short to ground.
  2. Replace the rear compartment lid release motor if CKT 56 is functional.

Is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

18

  1. Test CKT 1576 for a short to ground.
  2. Replace the BCM if CKT 1576 is functional. Refer to Body Control Module Replacement in Body Control System.

is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

19

  1. Test CKT 1576 for an open or high resistance between the trunk release switch connector terminal D and the BCM connector C2 A7.
  2. Replace the BCM if the CKT 1576 is functional. Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

20

Inspect the remote rear compartment lid release system for correct operation.

Is the remote rear compartment lid release operating correctly?

--

Go to Diagnostic System Check - Body Rear End

--

21

Replace the trunk release relay.

Is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

22

Replace the trunk release switch.

Is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

23

Replace the rear compartment lid release motor.

Is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

24

Replace left IP wiring harness junction block.

Is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--

25

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

Is the repair complete?

--

Go to Diagnostic System Check - Body Rear End

--