Lift gate and window will not lock

[Spaceman Spiff]

2005 Tahoe. Lift gate and lift gate glass will not lock with controls on the drivers door, or the ( aftermarket) key fob. There is no keyhole in the lift gate. What should I look for?

 

[avalonandl]

I think either a disconnected locking rod or a bad wire....

Remove inner panel on tailgate- CAREFULLY