SANDY21

i have a 2003 v6 mustang. I noticed my a/c when turned on cold is blowing warm air. we checked all fuses and they are good also it is full of Freon so no leak. also the orfus was stoped up so had it changed and the air vaccumed out and new Freon put in.


what I need help with is under my steering colomn there is a box of fuses which is my fuse junction box but behind the box there is a box of 4 black relays with all the same numbers on them. I think the box of relays is called the intercooler. I need to know which relay is for my a/c I can not find anything online to help me in which relay to change.


any help will be awesome and greatly appreciated.

corker

Head over to the site below and pull up the wiring diagram for the HVAC system controls. The quick and dirty way to see if the system works is to turn the system on inside the car and supply a ground to the correct wire on the A/C compressor clutch coil (while connector is on). If compressor runs, then PCM is not supplying a ground for some reason. You will have to check all switches in series to see if there is a fault. You can also supply 12v to the A/C compressor clutch coil, but make sure you know which wire supplies 12v. You can damage PCM if you supply 12v to the PCM ground wire

http://www.bbbind.com/free_tsb.html

SANDY21

That really did not help much. I need to know which relay is what. That did not tell me which one was ac relay. But thank you corker.

corker

I think you're barking up the wrong tree. I don't believe the relays under the dash control your A/C functions. The A/C functions are controlled by the PCM & the CCRM (constant control relay module) under the hood by the coolant overflow reservoir. That is where you can utilize the link to the wiring diagrams I included to see if the PCM is commanding the A/C clutch relay on (inside the CCRM) to pull in the A/C clutch coil. Looks like the BK/YE wire supplies power to the clutch coil from the A/C clutch relay inside the CCRM. The clutch coil is grounded through the BK wire.