To find the likely culprit, you need to consult your owner's manual. It will have a fuse box diagram showing which fuses control which circuits. Look for fuses related to the following:
* Power locks: The rear hatch lock is often part of the central locking system.
* Power windows: The rear hatch window (if it has one) might share a fuse with other windows.
* Accessory power: Some rear hatch functions might be on an accessory circuit.
* Body control module (BCM): The BCM is a central computer that controls various functions. A fault in the BCM itself could prevent the hatch from working, though you'd need a diagnostic tool to check this.
Without your owner's manual, it's impossible to pinpoint the exact fuse. Checking all the fuses in the under-hood and interior fuse boxes (there are usually two) is the best approach. Look for any that are blown (the wire inside will be broken or melted). Replace any blown fuses with ones of the same amperage. If the problem persists after checking all fuses, it's likely a wiring problem, a faulty switch, or a more significant electrical issue requiring professional diagnosis.
