I have a 2011 charger police pack and the heater or A/C womt turn on. They all light up and so does the screen so it cant be a fuse. I press on the ON button and nothing hapens and not even the rear defrost work nothing related to the climate control. Any suggestions???

SOURCE: Rear defrost is not working

Take your vehicle to the garage who would inspect the car circuit.

SOURCE: climate control not working

I had the same problem on my 2004 GMC Yukon XL.
Still under warranty the shop was able to reprogram the climate control system and tell what was wrong rather quickly with a OBD computer.
That’s when they found both of the climate control (driver and passenger) side actuators were bad and the control unit that tells the actuators where they should be was also bad.
The truck was in the shop with most all the dash, seats, consol, and steering wheel out for a week. The cost was over $1200.00.
That has seamed to fix the problem. Good Luck.

SOURCE: a/c heater climat control switch

Check the relais module located inside under the rh side of the heather box you can see the connector most of them need to be replaced as they burn out you may need to replace the blower motor as well,high amp draw caused by faulty bearings will overload the blower motor controller

SOURCE: 2005 GMC Yukon Denali XL - Climate Control issue-

Are you aware of any codes that may stored in the body control module and do you hear a clicking or ticking noise in the rear?

SOURCE: My rear defroster stopped working.

Check to see that the wires that connect to the rear window are indeed intact...then you will need to look at the lines in the window to be sure none of then are broken...to go further, you will need a voltmeter...hook up the voltmeter across the two leads that connect to the window and turn on the system to see if it delivers 12 volts to the window...if so then the connections are either bad or the wires inside the glass are open