Hi Lisa, I take it that you have the long wheel base version. The clicking you're hearing is an actuator for the HVAC. These can be blown by a disconnected battery. With an intermitent problem like this, check your battery connections, make sure they're good and tight. Gauges going whacko, is probably your ignition switch, or ground. Check the ground on the transmission hump on passenger side. 1 screw to pull the carpet back, it will be right under there. This ground handles a lot of things.

Strange intermittent problems like this can be caused by a faulty ground in the vehicle - I would check all the ground straps for loose or corroded connections. Looking at trouble codes in the vehicle using a code reader may also shed some light on this.

May be some wiring fault but to know the exact fault you must need the service and repair manual with diagram which will provide you step by step help to locate and fix the problem easily and you will get the manual from the given link https://toolsnyou.com