Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Does your Suburban have the liftgate, or the double rear doors?
Please also note that key port in bumper is just the lock for the spare tire hoist.
There is no separate fuse for the liftgate. Normally this problem is caused by failure of the liftgate lock actuator. The lock actuator must be replaced to fix the problem.
You operate the locks with your remote while you listen at the liftgate. If you hear the lock clicking inside the liftgate and trying to operate then you know it is getting power. This would then definitely confirm that the actuator must be replaced.
Are you listening right at the rear door?
The problem could be in the actuator or the wiring. Only way to know for sure would be to test wiring with a visual check or by testing voltage. The wires can break in the conduit between the body and liftgate. This can be determined with a visual inspection. If the wires are not broken then testing voltage to the actuator will tell you for sure whether the actuator will need to be replaced.
Normally if the wires are not broken then the actuator has failed.