My son's 2003 Tahoe has a liftgate that won't open. He bought a new actuator online, but changing that out did not fix it. Neither actuator does anything when connected to the wiring harness and the fob is pushed to unlock. The fob does lock and unlock all the other doors. Makes me think it is electrical. All fuses look to be fine. Anyone know which fuse would be the one covering the door opening? Second, if I put the probes from my multimeter into the wiring harness, it should register a current when the unlock on the fob is pressed, correct?