Cadillac Repair: AC, electrical harness, track thanks

Question
QUESTION: CAR IS AT NORMAL OPERATING TEMP.THERE IS NO POWER AT THE SINGLE WIRE GRAY WITH BLACK STRIPE...THANKS TOM

ANSWER: replace the power module.

---------- FOLLOW-UP ----------

QUESTION: HI WHEN YOU SAY POWER MODULE DO YOU MEAN THE CARS ECM OR THE HEATER AC PROGRAMMER...JUST WANT TO CHECK SO IM ON THE RIGHT TRACK...THANKS FOR ALL YOUR HELP TOM   HAVE A NICE REST OF THE DAY..

Answer
The power module is in back of the switch with the gray wires and has a multi-wire electrical harness plugged into the top of it and has a big black wire that grounds to the firewall. It is held inplace by 2 7mm screws and when you lift it out you will see abig aluminum finned heat sink attached to the bottom of it.