GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

DEFINITION: The endgate window release function on the rear wiper/washer switch does not operate.

1

Has the Endgate Release System Check been performed?

--

Go to Step 2

Go to Endgate Release System Check or Endgate Release System Check

2

  1. Apply the parking brake. Do not release the parking brake until you complete this diagnostic procedure.
  2. Unlock the right front door. Do not lock the door until you complete this diagnostic procedure.
  3. Determine if the vehicle has an automatic transmission.

Does the vehicle have an automatic transmission?

--

Go to Step 3

Go to Step 4

3

Place the transmission in the PARK position.

Do not move the transmission out of the PARK position until you complete this diagnostic procedure.

Is the transmission in the PARK position?

--

Go to Step 4

--

4

  1. Turn the ignition switch to the OFF position.
  2. Install a scan tool.
  3. Turn the ignition switch to the RUN position.
  4. Check the scan tool for the following switch inputs:
  5. • Park Brake - SET
    • Transmission Position - P
    • Rear Gate Ajar - CLOSED

Are all of the inputs correct?

--

Go to Step 5

Go to Brake Warning Indicator Inoperative in Hydraulic Brakes

Go to PRNDL Display Inaccurate or Inoperative and/or Gate Ajar Indicator Inoperative in Instrument Panel, Guages, and Console

5

Attempt to operate the window release with the endgate lock cylinder switch.

Does the window release actuator operate correctly if the endgate lock cylinder switch is used?

--

Go to Step 10

Go to Step 6

6

Inspect the MIR/LKS fuse in the underhood fuse block.

Is the fuse good?

--

Go to Step 8

Go to Step 7

7

Locate and repair the short to ground in CKT 840 (ORN), CKT 1221 (WHT/BLK), and/or CKT 56 (BLK/WHT) and replace the fuse.

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

8

Connect a test lamp from ground to the power supply side of the MIR/LKS fuse in the underhood fuse block.

Does the test lamp light?

--

Go to Step 10

Go to Step 9

9

Repair the open power supply circuit to the MIR/LCK fuse in the underhood fuseblock.

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

10

  1. Connect a test lamp from ground to connector C1, terminal B6 of the underhood fuse block
  2. Momentarily connect a fused jumper wire from ground to the underhood fuse block connector C1, terminal B5.

Does the test lamp light?

--

Go to Step 12

Go to Step 11

11

Replace the endgate liftglass relay.

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

12

Using a Digital Multimeter (DMM), check for continuity from the underhood fuse block connector C1, terminal B6 to the body relay block terminal D11.

Is there continuity?

--

Go to Step 14

Go to Step 13

13

Locate and repair the open in CKT 56 (BLK/WHT) between the body relay block terninal D11, through the body relay block to terminal D12, to the underhood fuse block connector C1, terminal B6

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

14

Using a DMM, check for continuity from the underhood fuse block connector C1, terminal B5 to the BCM connector C2, terminal A6.

Is there continuity?

--

Go to Step 16

Go to Step 15

15

Locate and repair the open in CKT 1344 (LT BLU).

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

16

Using a DMM, check for continuity to ground from the rear wiper/washer switch and endgate window release switch terminal E.

Is there continuity?

--

Go to Step 18

Go to Step 17

17

Locate and repair the open in CKT 1850 (BLK) from the rear wiper/washer switch and endgate window release switch terminal E to ground G203.

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

18

Using a DMM, check for continuity to ground from the rear wiper/washer switch and endgate window release switch terminal D while activating the switch.

Is there continuity?

--

Go to Step 20

Go to Step 19

19

Replace the rear wiper/washer switch and endgate window release switch

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

20

Using a DMM, check for continuity from the rear wiper/washer switch and endgate window release switch terminal D to the BCM connector C3, terminal B1.

Is there continuity?

--

Go to Step 22

Go to Step 21

21

Locate and repair the open in CKT 1576 (BLK) from the rear wiper/washer switch and endgate window release switch terminal D to the BCM connector C3, terminal B1.

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

22

Connect a test lamp from ground to terminal D of the endgate lock cylinder switch.

Does the lamp light?

--

Go to Step 24

Go to Step 23

23

Locate and repair the open in CKT 840 (ORN).

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

24

Connect a test lamp from ground to terminal C of the endgate lock cylinder switch and depress the switch.

Does the lamp light?

--

Go to Step 26

Go to Step 25

25

Replace the endgate lock cylinder switch

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

26

Connect a test lamp from ground to connector C3, terminal B of the door lock cylinder switch and depress the endgate lock cylinder switch.

Does the lamp light?

--

Go to Step 28

Go to Step 27

27

Locate and repair the open in CKT 1221 (WHT/BLK).

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

28

  1. Ensure that the RH door lock cylinder switch is in the unlock postion
  2. Connect a test lamp from ground to connector C3, terminal D of the door lock cylinder switch
  3. Depress the endgate lock cylinder switch

Does the test lamp light?

--

Go to Step 30

Go to Step 29

29

Replace the RH door lock cylinder switch.

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

30

  1. Ensure that the RH door lock cylinder switch is in the unlock postion
  2. Connect a test lamp from terminal A of the endgate lock actuator to ground
  3. Depress the endgate lock cylinder switch

Does the test lamp light?

--

Go to Step 32

Go to Step 31

31

Locate and repair the open in CKT 56 (BLK/WHT).

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

32

Using a DMM, check for continuity to ground from the endgate lock actuator terminal B.

Is there continuity?

--

Go to Step 34

Go to Step 33

33

Locate and repair the open in CKT 1350 (BLK) from the endgate lock actuator to ground G450.

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--

34

Replace the endgate lock actuator.

Is the repair complete?

--

Go to Endgate Release System Check or Endgate Release System Check

--