GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2005 🢒 Rainier - 2WD 🢒 Body 🢒 Body Rear End 🢒 Endgate Latch Release Inoperative

Step

Action

Yes

No

Schematic Reference: Body Rear End Schematics

Connector End View Reference: Body Rear End Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Verify that the endgate latch release is inoperative.

Does the endgate latch release operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the endgate module to Drop End Gate.

Does the endgate drop open?

Go to Step 7

Go to Step 4

4
  1. With a scan tool, observe the right upper latch and left upper latch parameters in the End Gate Module data list.
  2. Activate the drop latch.

Does the scan tool display Active?

Go to Step 17

Go to Step 5

5
  1. Disconnect the upper left and upper right endgate latch electrical connectors.
  2. Probe the endgate latch relay supply voltage circuit of the upper left endgate latch electrical connector with a test lamp that is connected to a good ground.
  3. Probe the endgate latch relay supply voltage circuit of the upper right endgate latch electrical connector with a test lamp that is connected to a good ground.
  4. With a scan tool, command the endgate module to Drop End Gate.

Does the test lamp illuminate?

Go to Step 6

Go to Step 12

6
  1. Connect a test lamp between the endgate latch relay supply voltage circuit and the upper left endgate latch actuator circuit of the upper left endgate latch electrical connector.
  2. Connect a test lamp between the endgate latch relay supply voltage circuit and the upper right endgate latch actuator circuit of the upper right endgate latch electrical connector.
  3. With a scan tool, command the endgate module to Drop End Gate.

Does the test lamp illuminate?

Go to Step 18

Go to Step 13

7

With a scan tool, command the endgate module to Swing End Gate.

Does the endgate swing open?

Go to Step 11

Go to Step 8

8
  1. With a scan tool, observe the Right Upper Latch parameter in the End Gate Module data list.
  2. Activate the drop latch.

Does the scan tool display Active?

Go to Step 17

Go to Step 9

9
  1. Disconnect the upper left and lower left endgate latch electrical connectors.
  2. Probe the endgate latch relay supply voltage circuit of the upper left endgate latch electrical connector with a test lamp that is connected to a good ground.
  3. Probe the endgate latch relay supply voltage circuit of the lower left endgate latch electrical connector with a test lamp that is connected to a good ground.
  4. With a scan tool, command the endgate module to Swing End Gate.

Does the test lamp illuminate?

Go to Step 10

Go to Step 12

10
  1. Connect a test lamp between the endgate latch relay supply voltage circuit and the upper left endgate latch actuator circuit of the upper left endgate latch electrical connector.
  2. Connect a test lamp between the endgate latch relay supply voltage circuit and the lower left endgate latch actuator circuit of the lower left endgate latch electrical connector.
  3. With a scan tool, command the endgate module to Swing End Gate.

Does the test lamp illuminate?

Go to Step 18

Go to Step 14

11
  1. With a scan tool, observe the Swing Latch Switch and Drop Latch Switch parameters in the End Gate Module data list.
  2. Activate the swing latch and drop latch switches.

Does the scan tool display Inactive?

Go to Step 15

Go to Step 17

12

Test the endgate latch relay supply voltage circuit for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 19

13

Test the appropriate upper endgate latch actuator circuit for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 17

14

Test the appropriate left endgate latch actuator circuit for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 17

15

Test the appropriate endgate latch switch signal circuit for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 16

16

Test the appropriate endgate ajar switch low reference circuit for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 20

17

Inspect for poor connections at the harness connector of the endgate module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 21

18

Inspect for poor connections at the harness connector of the appropriate endgate latch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 22

19

Inspect for poor connections at the harness connector of the endgate latch relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 23

20

Inspect for poor connections at the harness connector of the appropriate latch switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 25

Go to Step 24

21
  1. Perform the endgate window learn procedure. Refer to Control Module References for replacement, setup, and programming.
  2. Replace the endgate module. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 25

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22

Replace the appropriate endgate latch. Refer to the following:

Did you complete the replacement?

Go to Step 25

--

23

Replace the endgate latch relay. Refer to Relay Replacement .

Did you complete the replacement?

Go to Step 25

--

24

Replace the appropriate latch switch. Refer to Endgate Handle Replacement .

Did you complete the replacement?

Go to Step 25

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25

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2