Rear hatch not latching

cshults

03-22-2007, 01:14 PM

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

03-22-2007, 05:44 PM

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

03-23-2007, 10:05 AM

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)

(http://service.gm.com/servlets/BlobShtml?ShtmlFile=735148&pubid=249&evc=sm#oth1-735148)
http://service.gm.com/engif/000/000/397/397727.gif

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)

(http://service.gm.com/servlets/BlobShtml?ShtmlFile=738964&pubid=249&evc=sm#oth1-738964)
http://service.gm.com/engif/000/000/357/357342.gif

atfdmike

03-23-2007, 10:13 AM

spddmn1

11-16-2007, 01:05 PM

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.

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Rear hatch not latching