QuestionThe a/c cools great for about 10 minutes then it starts blowing warm air. If you turn it off, wait awhile and turn it back on, it will be cool again for a little while.
AnswerStephanie,
Your compressor clutch is disengaging, that is the cause for the warm air. Your compressor clutch is controlled by your PCM (Powertrain Control Module). This is the vehicle brain. In order for it to allow your compressor to engage, it has several requiremants that must be met. I will help in any way I can.
The first thing I want you to do is locate your low pressure switch. This is located on your accumulator on the left side of the engine compartment near your strut tower. After running the vehicle until the compressor disengages, unplug the harness plug from the switch and with a small insulated wire to jump the terminals in the plug. Did your compressor come on? If so, this tells me that you either have a low refrigerant charge (not likely because it stays runnign for the first 10 minutes) you have a restriction drifting somewhere in the lines (probably the orifice tube) or your low pressure switch is going bad. If it does not engage...
The problem may lie in your compressor clutch relay. It may be heating up and disengaging the contacts inside it. This would cause power to not get sent forward to your clutch. Or... oneof the other requirements for the PCM to be happy may not be getting met. I am finding that the most typical "other requirement" not getting met is your engine temperature may be too high. Have you noticed your temperature gauge reading higher than normal. On most vehicles the PCM will disengage the compressor if the temperature gets up to about 250 defrees fahrenheit. The reason fo this is so that the radiator is able to dissipate heat quicker without having the condensor heat (located right in front of it) to fight against. If this is the case, usually changing the thermostat will cure it, but your truck may also require the coolant system to be flushed, depending on how bad off it is.
Thank you for the question, I hope I was of some assistance. If I can do anything further during this process, or in the future, please do not hesitate to ask. If you found this response to be of some assistance, please remember to rate this answer. Thanks again and good luck in everything.
