A/C Working Intermittently

[nhmatrixdriver]

I have a 2005 Matrix AWD. At about 55,000 miles, I had an A/C problem that I brought the Matrix to the dealer for. There are times, when starting the car, that the A/C does not come on right away. Sometimes it would come on a few minutes later, other times possibly longer. Unfortunately, it was working when I brought it to the dealer, so they said they couldn't fix it because it worked. This was approximately 2 yrs ago, and the problem eventually went away on it's on. Within the past week, it has started again. Sometimes the A/C works as soon as the car is on, sometimes it comes on a few minutes later. We have had a few hot, humid days lately where it has not come back on for a good 1/2 hour or did not come on at all during a hr ride. Any suggestions or similar experiences?

[fishexpo101]

Sounds like the system is low or too full of refrigerant (low/high charge), there is an intermittent problem with the magnetic clutch that engages the compressor, or there is an intermittent issue with the switch.

The system has built in safeguards that protects the compressor from damage - if there is too much pressure or not enough - the compressor will not come on.

Electrical issues can come from a multitude of sources - have to diagnose the system to find out what exactly is wrong. The intermittent behavior an be a pain - as lots of shops will not test the system unless there is a hard fault. Takes time to chase down an intermittent problem - I would suggest a better shop, if you can find one. Can be a good independant garage that specializes in Toyot, if you don't trust or have access to good Toyota dealerships.

[Vindicator]

First check the pressures at the lo and hi fittings. Then check to see if your getting 12 volts going to the compressor...