I recently purchased and had an Apline INA-W900 installed with a PAC bypass in my 2007 F150 FX4. The installer did something weird to blow a fuse that took out the lights for instrument panel. The installer fixed that fuse issue but now the dimmer will not increase or decrease for the instrument panel. However, the dimmer will turn the dome light on. Also, the back-light for the odometer is not working now. The dealer "assures" me those were working at the time of the sale.

Any suggestions would be greatly appreciated!

 

It was the dimmer switch that was faulty...surprise, surprise. This is a common F150 problem.

Next I'm going to try to replace the odometer light and hopefully that will solve the problem.

 

Replaced the odometer back light and viola fixed. Here is how to replace that light.

2007 f150 Odometer light - Ford F150 Forum