Genuine Chevrolet Trailblazer Door Lock

Chevrolet Trailblazer Door Lock Parts Questions & Answers

• Rear Side Door Lock Assembly
  25948725
  Q: How to operate and diagnose the power door lock system?

  A: The power door lock system operates the door lock actuators in each door, with the system consisting of switches, actuators, Body Control Module (BCM), and associated wiring. Diagnosis typically involves checking the wiring connections and actuators for minor faults that can be easily repaired. The system is operated by bi-directional solenoids located in the doors, with lock switches having two positions: Lock and Unlock. These switches send a signal to the BCM, which then sends a signal to the door lock solenoids. It is important to check the circuit protection first, as some vehicles use a combination of circuit breakers and Fuses. If no voltage is present at the switches, the wiring between the fuse panel and switches should be checked for shorts and opens. If voltage is present, the switch should be tested for continuity, and if there is no continuity in both switch positions, it should be replaced and check the wiring between the switch and the door lock solenoid. If all but one lock solenoids operate, the trim panel from the affected door should be removed to check for voltage at the solenoid while the lock switch is operated; if the inoperative solenoid is receiving voltage, it should be replaced and if it isn't, an open or short in the wire between the lock solenoid and the relay should be checked. For the keyless entry remote, the battery should be replaced when the transmitter doesn't operate the locks at a distance of ten feet, with the normal range being about 30 feet. To replace the battery, the case halves should be carefully separated using a small screwdriver, and then the three-volt, lithium battery should be replaced before snapping the case halves together.