GMC Envoy rear tail lights not working despite good fuses, bulbs, and relay on GMC Envoy

Some GMC Envoy owners report experiencing issues with rear tail lights not functioning despite having good fuses, bulbs, and relays. These problems can stem from using incorrect or faulty bulb types, which may prevent the tail lights from working properly even when brake lights are operational. Additionally, bad wiring, such as corroded sockets or plugs, can lead to malfunctions in the tail light system. Some owners have found that a fuseblock issue may exist if there is power to the rear fuses but not to the wires leaving the fuseblock towards the brake lights. Furthermore, a break in the circuit from the fuse box to the brake pedal can result in all brake lights failing to operate, necessitating a thorough tracing of the circuit to locate the power loss. Lastly, since tail lights function as parking lights, it is crucial to check the 10amp fuses in the rear fuse box to ensure they are intact. Systematic troubleshooting of these components is essential for identifying the root cause of the tail light issues.