My digital display for my heating and ac control does not light up but the heater still seems like it is working I don't know ,is there a fuse or relay that will fix this ?

seems? (why guess?) (fuses are black/white deal)
3 non related systems failed, hummmmm
check fuses with a walfart $10 meter, on low OHMS> Rx1.

1. 0 ohms is good
2. infinity is bad.

fuses that look good, can in fact be bad. (hair line cracks)
so test them and avoid, SEEMS?
Rear glass heater is a hot wire heater.
if it has 12vdc to the wire and no heat the grid is bad (open)
if no 12v there, then the relay/fuse or switch to it is bad,
the voltmeter finds this in 5min work.
Hazard not working (but are blinkers> dead? on either sided?)
again fuses.
Dash board dead, (cluster) FUSES.

A.C. not working (the FSM and alldata.com cover this)
1: fuse , check fuese
2: if heater fan is dead, so will be AC.
3: A/C clutch not engaging for 6 reasons , ask. for list of tests.
all tests are in the FSM. BTW.

my wild guess, is you are working on car that has not run
right for a long time? accumulated, issues?

Have you checked your fuses? Start there and let us know if you find a blown fuse.

the controls dont respond when you turn the engine off ???? engines off not suppose to turn controls, ac comes on..... how do you know are you talking about the ac light or is coming out cold and hot at the same time more info please if u want to temporarily fix issue until summer take ac fuse out

where 2 find d ac fuse

a chevy.

heater control valve...check hoses going into heater core..both must be hot if heater control valve is good ..check flapper valve that closes off ac from heat..this is a door inside the duct work....thermostat replaced and radiator cap too.let me know just fixed my own

take it back and tell them AC ok but you broke the heat bend damper
and GRIN !

check the ground.

Change the 15amp fuse in the kicker fuse panel labeled cig. My stopped working for the same reason.

U must remove the climate control unit from the dash and remove the top cover of the unit, u will find a tiny twist in light bulb socket with a tiny little light bulb, this provides the backlight for the AC/heater display, u can buy the bulb at any auto parts store, couple of bucks.