In most cases when the HVAC screen is dim or goes blank there is 5 surface mount resisters that need to be re-soldered shown below.

All 8 screws to take head unit apart need a 3/16 hex head socket.

Attached Files hvachead.jpghvachead2.jpghvachead3.jpghvachead4.jpg

Team ZR-1
True Custom Performance Tuning
Teamzr1.com