Central locking button not functional and I can't lock the rear door glass

Sorry Andrew , no BCM on this vehicle . The Central Security Module is incharge of power door locks . Central Security Module For additional information, refer to Section 419-10 .
The central security module is equipped with a battery back-up which holds the programmed transmitter(s) memory in the event of the vehicle battery disconnection.
Principles of Operations The Door Switch Lock Function When a door lock switch is moved into the lock position or a door lock cylinder is rotated to the lock position, the door lock switch grounds the lock circuit input to the central security module. The central security module then provides 12 volts to one side of the door lock actuators contained in the door latch unit and simultaneously grounds the other side of the door lock actuators. This completes the door lock actuator circuit, causing the door lock actuators to rotate a cam assembly, which then locks the doors.

The Door Switch Unlock Function When a door lock switch is moved into the unlock position, the door lock switch grounds the unlock circuit input to the central security module. The central security module then provides 12 volts to the opposite side (relative to locking the door) of the door lock actuator(s) contained in the door latch unit and simultaneously grounds the other side of the door lock actuator(s). This completes the door lock actuator circuit, causing the door lock actuator(s) to rotate a cam assembly in the opposite direction, which then unlocks the door(s). The 12 volts which the central security module provides to the door lock actuator(s) are provided to each door lock actuator from the individual pins on the central security module connector.

Keyless Entry When a remote transmitter button is depressed, it transmits the appropriate command to the central security module as a radio frequency. The central security module receives the command from the remote transmitter through an antenna, which is incorporated in the central security module.
When the central security module receives a command from the remote transmitter, it then sends the appropriate output to control the desired devices. These outputs devices include:

• The front and rear door lock units.
• Central timer module (CTM).
• The liftgate release motor.
• The right and left side turn signal lamp(s).

The central security module sends a signal to the CTM when courtesy lamp illumination is required.
Computer Operated Locks Each front door lock actuator contains a bipolar motor that controls the lock and unlock linkage. The lock/unlock lever of both front door interior handles use linkage to actuate the lever lock switch located inside each front door lock actuator. Each lever lock switch remains in the unlock position until lock/unlock lever of the interior door handle is moved to the lock position. This action toggles the lever lock switch to the lock position. The central security module uses only one electrical input for both lever lock switches. The central security module cannot determine whether the driver or passenger door lever lock switch was actuated. Therefore, actuating the lock feature from either front door will have the same affect of locking all doors. Actuating the unlock feature will not unlock any other door.
The door lock control switches for both front doors also use only one input to the central security module.
Both rear passenger doors contain a rear door lock actuator that controls only electric lock or unlock of the door. Actuating the lock/unlock lever at either rear passenger door will have no effect on other doors.
The panic feature of the remote transmitter sounds the vehicle horn when the vehicle is not equipped with anti-theft. If the vehicle is equipped with anti-theft feature, a separate horn is sounds for the panic feature.

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The fuses are not likely culprit, What you must do first is to observe all your door locking functions and check if doors are closing properly. If door locks wont function when using the door buttons but works on remote buttons only, there are many possible causes. Door lock switches, sensors, and even the body control module. A deeper diagnosis will be required.

Use the key fob to open the rear doors by pressing the unlock function twice. If you need reprogramming instructions, use the following:

2002 Focus

1. Turn the ignition from OFF to RUN 4 times within 6 seconds.
2. Turn the ignition OFF. The system will chime to confirm programming mode.
3. Within 20 seconds, press any button on first keyless remote. The system will chime once to confirm programming.
4. Within 20 seconds, press any button on second keyless remote. System will chime once to confirm programming.
5. Turn ignition to RUN to exit programming mode.

This solution applies to models:
2002-2007 Chevrolet Trailblazer, Trailblazer EXT and Trailblazer SS
2004-2007 Buick Rainier
2002-2007 GMC Envoy, Envoy XL, and Envoy Denali
2002-2004 Oldsmobile Bravada
2005-2007 Saab 9-7x

Condition/Concern:
Rear liftgate glass will not lock when using the key fob or door switch unless the lock button is pressed a second time. All other doors will lock normally. This could be the result of the liftgate glass lock rod not adjusted correctly. This lock rod travels from the liftgate lock actuator to the glass release push-button cylinder.

Recommendation/Instructions:
Remove the inside rear liftgate trim panel. Disconnect the threaded lock rod clip at the end of the push-button glass release and rotate this clip 1 complete turn at a time making the lock rod longer. This will be the only threaded lock rod visible when the trim panel is removed and the liftgate is raised.
Note: For the rear glass to release, the rear liftgate latch must be in the closed position. For test purposes only, this latch can be made closed to make this lock rod adjustment.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

I assume you mean that the central locking system will not lock the doors but you can do so manually.

Get inside the vehicle and close all doors.

On each rear door, lock and unlock the mechanism manually a couple of times. In other words do not use the key pad.

Then leave both rear doors in the locked position (manual locking) and operate the lock button on you key pad to operate the central locking system. Wait a few seconds then hit unlock on your key pad and a few seconds later hit lock on your key pad.

If the system fails to lock your rear doors you will need to get the vehicle to an auto electrician to check out the issue and rectify it for you. There are a number of possible causes which cannot be identified without physically checking the system. So you will need to have this rectified by a professional.

I assume you mean that the central locking system will not lock the doors but you can do so manually.

Get inside the vehicle and close all doors.

On each rear door, lock and unlock the mechanism manually a couple of times. In other words do not use the key pad.

Then leave both rear doors in the locked position (manual locking) and operate the lock button on you key pad to operate the central locking system. Wait a few seconds then hit unlock on your key pad and a few seconds later hit lock on your key pad.

If the system fails to lock your rear doors you will need to get the vehicle to an auto electrician to check out the issue and rectify it for you. There are a number of possible causes which cannot be identified without physically checking the system. So you will need to have this rectified by a professional.

You mean that the central locking system will not lock the rear doors but you can do so manually.

Get inside the vehicle and close all doors.

On each rear door, lock and unlock the mechanism manually a couple of times. In other words do not use the key pad.

Then leave both rear doors in the locked position (manual locking) and operate the lock button on you key pad to operate the central locking system. Wait a few seconds then hit unlock on your key pad and a few seconds later hit lock on your key pad.

If the system fails to lock your rear doors you will need to get the vehicle to an auto electrician to check out the issue and rectify it for you. There are a number of possible causes which cannot be identified without physically checking the system. So you will need to have this rectified by a professional.

Does that doors' lock get any power when you hit the button to lock? You may have to check the wiring going to the door and search the internet to find out what wire gives power to the lock.

1st wind the glass down and turn the key in the driver door twice in clockwise direction to lock, at the sound of the second click try try opening the door thru the window (passenger) manually. you will need to pull the knob twice before it opens. you can get all the passenger doors open this way until you decide to change central lock system. To activate the remote; insert the key into driver door while pressing the lock or unlock button on the remote for at least five-ten seconds which should get it functioning normally again. hope this helps. it worked on mine.