Rear hatch not latching

[cshults]

I'm having a problem getting the rear glass hatch to latch. I can't figure out why the locking mechanism is not latching. The glass closes but the lock does not latch it shut. There does not seem to be any obstructions in the way, I sprayed the mechanism with penetrating oil to free up any joints that may have been froze up but it is still not latching. Any ideas before I take it to the shop and have them tell me the whole assembly needs to be replaced.

[Rammer500]

Rear Hatch/Gate Description and Operation General

The lift glass can be opened by any of the following components:

Lift gate window release switch
Door lock cylinder switch
Keyless entry transmitter

When the lift gate window release switch is operated ground is applied to the body control module (BCM) and a lift glass release output is sent to the lift glass relay. An open output can also be commanded by the BCM when an open input is received from the remote control door lock receiver. When the BCM grounds the relay with a commanded open the lift glass relay coil energizes and the switch side of the relay closes. Battery voltage is then applied directly to the lift gate window release actuator. This will release the lift glass. The lift gate window release actuator can also be energized when the lift gate lock cylinder switch is operated.


Try pulling the lift glass relay from the under hood fuse box. If the glass will latch, this relay is stuck in the closed position or the input wire going to the body control module is grounded.

The relay is a long shot, as most relays quit in the open position, but it might be your problem and is the easiest to check.

Next step would be to remove the interior trim pieces and inspect the latch.

[atfdmike]

Hi, sometimes they have a two latch mechanism, but I am not sure for your vehicle. If you look down at the latch while hatch is closed but window open, you should see that there could be actually two movable levers that hold the window shut. One is like a safety, and both need to be in a position to accept the pawl on the window. Since the window will not lock, but appears shut, I am guessing the smaller retainer (if there is one) may have moved enough to have returned to the closed position, which will not let the window pawl go deep enough to let the primary lock engage.
Kind of hard to describe but you can take a long slender screwdriver or hook and look for both latching features.....I think they should be U shaped for both, and make sure they are both tipped up to receive the window pawl. If they look ok, then maybe there really is something wrong with the mechanism. One guys opinion.
FIGURE Endgate Harness Routing View(c)




1)Window Wiper Motor Controller - Rear (2)Rear Window Wiper Cutout and Liftglass Ajar Jamb Switch(3)P900(4)Endgate Harness(5)Liftglass Release Actuator(6)Liftglass/Endgate Lock Cylinder Switch(7)Endgate



FIGURE Liftglass Release Actuator(c)

[atfdmike]

More stuff:



Endgate Window Release Inoperative

Step
Action
Yes
No
1
Did you perform A Diagnostic System Check - Body Rear End?
Go to Step 2
Go to Diagnostic System Check - Body Rear End
2
Operate the rear wiper/washer and endgate/liftgate window release switch.
Does the endgate window release?
Go to Step 3
Go to Step 6
3
Operate the liftgate/endgate lock cylinder switch.
Does the endgate window release?
Go to Testing for Intermittent and Poor Connections in Wiring Systems
Go to Step 4
4

1. <LI type=1>Disconnect the liftgate/endgate lock cylinder switch.
2. Connect a test lamp between the liftgate/endgate lock cylinder switch and a good ground.

Does the test lamp illuminate?
Go to Step 5
Go to Step 23
5

1. <LI type=1>Connect the liftgate lock cylinder switch. <LI type=1>Disconnect the door lock cylinder switch, LH. <LI type=1>Connect a test lamp between the door lock cylinder switch and a good ground.
2. Operate the liftgate lock cylinder switch.

Does the test lamp illuminate?
Go to Step 13
Go to Step 14
6

1. <LI type=1>Install a scan tool. <LI type=1>Turn ON the ignition with the engine OFF. <LI type=1>With a scan tool monitor the liftgate window release switch input.
2. Operate the liftgate window release switch.

Does the parameter change states?
Go to Step 9
Go to Step 7
7

1. <LI type=1>Disconnect the liftgate window release switch.
2. Connect a fused jumper between the liftgate window release switch signal circuit and a good ground.

Does the scan tool parameter change states?
Go to Step 8
Go to Step 15
8
Connect a fused jumper between the liftgate window release switch signal circuit and the liftgate window release switch ground circuit.
Does the scan tool parameter change states?
Go to Step 17
Go to Step 24
9

1. <LI type=1>Remove the liftglass relay.
2. Connect a test lamp between the liftglass relay battery positive and a good ground.

Does the test lamp illuminate?
Go to Step 10
Go to Step 25
10
Connect a fused jumper between the liftglass relay battery positive and the liftgate window release actuator signal circuit.
Does the liftglass release?
Go to Step 16
Go to Step 11
11

1. <LI type=1>Disconnect the liftgate window release actuator.
2. Connect a test lamp between the liftgate window release actuator signal circuit and a good ground.

Does the test lamp illuminate?
Go to Step 12
Go to Step 26
12
Connect a test lamp between the liftgate window release actuator signal circuit and the liftgate window release actuator ground circuit.
Does the test lamp illuminate?
Go to Step 21
Go to Step 27
13
Test the door lock cylinder switch, LH control circuit for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 22
14
Test the liftgate lock cylinder switch control circuit for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 20
15
Test the liftgate window release switch signal circuit for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 18
16
Test the relay control circuit for a high resistance or and open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 28
17
Inspect for poor connections at the harness connector of the liftgate window release switch. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 19
18
Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 29
19
Inspect for poor connections at the harness connector of the liftgate window release switch. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 30
20
Inspect for poor connections at the harness connector of the liftgate lock cylinder switch. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 31
21
Inspect for poor connections at the harness connector of the liftgate window release actuator. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 32
22
Inspect for poor connections at the harness connector of the door lock cylinder switch, LH. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
Go to Step 33
23
Repair the battery positive voltage circuit of the liftgate lock cylinder switch. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
--
24
Repair the ground circuit of the liftgate lock cylinder switch. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
--
25
Repair the battery positive voltage circuit of the liftglass relay. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
--
26
Repair the signal circuit of the liftgate window release actuator. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
--
27
Repair the ground circuit of the liftgate window release actuator. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 34
--
28
Replace the liftglass relay.
Did you complete the replacement?
Go to Step 34
--
29

Important

When replacing the body control module (BCM) refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.

Replace the (BCM). Refer to Body Control Module Replacement in Body Control System.
Did you complete the replacement?
Go to Step 34
--
30
Replace the liftgate window release switch.
Did you complete the replacement?
Go to Step 34
--
31
Replace the liftgate lock cylinder switch. Refer to Lock Cylinder Replacement - Endgate or Lock Cylinder Replacement - Liftgate .
Did you complete the replacement?
Go to Step 34
--
32
Replace the liftgate window release actuator. Refer to Lock Actuator Replacement - Rear Compartment Lid .
Did you complete the replacement?
Go to Step 34
--
33
Replace the door lock cylinder switch, LH.
Did you complete the replacement?
Go to Step 34
--
34
Operate the system in order to verify the repair.
Did you correct the condition?
System OK
Go to Step 2

[spddmn1]

My wife's hatch did the same thing on her 01 Bravada. The latch was rusty. So i pulled the latch out & sand blasted it. Put back together & spayed it with grease. Works great now.