To find the source of the problem (if your trunk release isn't working), you should:
1. Check the fuses: Start by checking the relevant fuses in both the underhood fuse box and the interior fuse panel. Your owner's manual will show you which fuses control the power trunk release.
2. Inspect the BCM: The Body Control Module is the brain of many electrical functions. A faulty BCM could prevent the trunk from releasing. Diagnosing BCM issues usually requires a scan tool to check for diagnostic trouble codes (DTCs).
3. Trace the wiring: If fuses are good and the BCM appears fine, you might need to trace the wiring from the trunk release switch to the trunk latch mechanism. Look for breaks, shorts, or corrosion in the wiring harness. This requires a deeper understanding of automotive electrical systems.
4. Consult a wiring diagram: A wiring diagram specific to your 1995 Cadillac DeVille will show the exact path of the electrical circuit for the trunk release. This is the best way to pinpoint the relay or other component that's malfunctioning. You can often find these diagrams online or in a repair manual.
Because it's integrated into the car's electrical system, pinpointing the exact location of the *function* is difficult without a schematic. It's best to focus on troubleshooting the system as a whole rather than searching for a specific "switch."
