I have a 2007 trailblazer the front doors lock works but my rear door locks don't change the locks and still don'work doesn't work with switch or fob but fronts do

BCM is bad or has no power.

None < LGM - liftgate control module inside the lift gate does .
Rear Wiper/Washer System Components
The rear wiper/washer system consists of the following components:
• Rear window wiper motor
• Rear washer pump
• Rear wash relay
• Rear wiper/washer switch
• RR WIPER Circuit Breaker 15A / ENDGLASS REG Circuit Breaker 30A
• WASH 20A fuse
• Body control module (BCM)
• Liftgate control module (LGM) / End gate module (EGM)

Your best bet , take it to a qualified repair shop. You have no idea of the complexity of these system's . Communication network between modules etc..... Could have DTC'S diagnostic trouble code's stored in the liftgate control module . An auto parts stores can not read these codes .

Power Door Lock Operation
The power door lock switches are integral components of the DDM and PDM. The switches are two position normally open rocker switches. When placed in either the lock or unlock positions, the switches provide a direct input to the DDM or PDM. The DDM or PDM monitors these inputs and sends a Class 2 message indicating a change in the switch's respective position. Modules which activate the power door lock motors receive the Class 2 message and activate the motor in the appropriate direction to lock or unlock the vehicle's doors and liftgate. The modules which activate the power lock motors are:
• DDM (driver door lock actuator).
• PDM (passenger front door lock actuator).
• BCM (both rear door lock actuators).
• LGM (liftgate door lock actuator).
The DDM, PDM and LGM are directly connected to the respective door lock actuator through the door lock motor lock and unlock circuits. Once a door lock or unlock request has been received, the module will supply battery voltage to one side of the actuator and ground the other causing the doors to lock or unlock.

Manually unlock Trailblazer lift gate hatch Trailblazer SS LS2 Envoy

The receiver for the fobs is located in the rear hatch, and it needs to be reprogrammed to the fobs. Try the following procedure;

1. Close all the vehicle doors.
2. Insert the ignition key into the ignition lock cylinder.
3. Press and hold the door unlock switch.
4. While holding the door lock switch in the unlock position, cycle
the ignition ON, OFF, ON, OFF.
5. Release the door unlock switch. The doors will lock and unlock to
confirm the program mode.
6. Press and hold the LOCK button and the UNLOCK button
simultaneously on one transmitter. After a delay of approximately 15
seconds, the doors will lock and unlock to confirm the programming of
that transmitter.
7. Repeat the previous step to program up to four transmitters.
8. Turn the ignition switch to the RUN position in order to exit the
keyless entry transmitter mode.
9. Operate the transmitter functions in order to verify correct
system operation.

Can be issue with the switch.
Help links are provided below for detailed procedure,Click the link below:---
Front Door dis-assembly diagram for Toyota car?

http://repairhelpcenter.blogspot.in/2012/02/front-door-dis-assembly-diagram-for.html

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Rear Door dis-assembly diagram for Toyota car?

http://repairhelpcenter.blogspot.in/2012/02/rear-door-dis-assembly-diagram-for.html

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How to test Power door locks? http://repairhelpcenter.blogspot.in/2012/02/how-to-test-power-door-locks.html

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right side slide door light switch on Toyota Sienna? http://repairhelpcenter.blogspot.com/2012/01/details-for-replacing-right-side-slide.html

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Door locks not working? http://technoanswers.blogspot.com/2012/01/door-locks-not-working-on-ford-explorer.html

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Power door locks not working? http://schematicsdiagram.blogspot.com/2011/12/power-door-locks-not-working.html

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Repairing car Door lock Actuator?
http://howtobyme.blogspot.com/2011/11/repairing-car-door-lock-actuator.html

How to Access car door panel?
http://howtobyme.blogspot.com/2011/11/how-to-access-car-door-panel.html

Vehicle door panel components?
http://howtobyme.blogspot.com/2011/11/vehicle-door-panel-components.html

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This will help.
Thanks.

Yes it is,the drive door actuator being non op

Sounds like a fuse. Are you getting power to the driver door module (control cluster as you say). Below are 3 pictures for you. The first one is the location where the fuse box is located for that fuse (under drivers seat in the rear). The second picture is a diagram or the latout of the fuses. The fuse you want to check is the fuse marked "LT DOORS" or the one marked 02. It should be a 25 amp fuse. The 3rd picture is a wiring diagram for the circuit. If the fuse isn't blown check the power wire from the fuse box to the driver door control module. Sounds like a power issue. Anymore questions or diagrams that you need, feel free to email me at [email protected] and I should have and will send if you need anything else. I hope this helps and good luck.

Sounds like body computer is malfunctioning or the module that controls the door locks lost it's program.Disconnect the battery for few minutes then reconnect and check.In some cases this resets the system computer and all starts working.But if that does not helps then problem has to be checked with the power door lock system.Either a power door lock actuator or the power door lock switch. Usually the most common problems with power door locks are the actuators. They are small electric motors used to lock and unlock the car doors when activated by a switch or remote. Like any electric motor sooner or later it will fail. Replacing an actuator involves removing the interior door panel for access. Some are part of the door latch and some are independent.
Either way, door lock actuators need to be replaced if they are buzzing, working only in one mode or are not working at all. if the problem is with the door lock actuator or just the switch. If a All the door locks, only work when locking and NONE of them work to unlock, then the switch is most likely the cause.

Thanks. Keep updated for any more query. You can rate this solution and show your appreciation

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.