Howdy Y'all!

Got a 2003 Corolla with a weird A/C problem. The Air Compressor won't stay engaged.
It'll come on briefly then shut off again. It's full of freon, and when it does come on, it cools
real good. I originally thought that it was the high pressure switch so I replaced it. Vacuumed
the system down and tried to fill it ... but the compressor wouldn't come on at all then. I ran a
hot wire to the compressor to get a reading on the gauges and after it pulled in some freon, it
stayed on. It stayed on (with out the jumper) long enough to fill the system and ran for a bout
5 min. then it shut off again and wouldn't come back on.
Any ideas??? Is there a Low pressure switch on this thing somewhere??? ... or does anyone
know what I might need to look for??
Thanks!!

I have the exact same problem with my 1993 Tercel! They use the same basic a/c system in all 'yotas, but change some part numbers around. I can't tell you what is causing it yet, but I can tell you what is not. I've replaced the following with no luck:

A/C Compressor
Filter/Drier
Expansion Valve
Pressure switch in front of the condensor
A/C amplifier
Magnetic clutch relay
Recharged a/c system

The only thing left to replace is the evaporator and it's pressure switch or the condensor.


I applied 12VDC to the condensor fan motor - it works fine. I removed the mag clutch relay and jumpered pin 2 and 4 together on the plug (this keeps the compressor clutch and condensor fan motor running) and it keeps the a/c frosty cold. This is only a temp fix until I can find the real culprit (leaving it this way for thousands of miles will probably cause premature compressor failure).

Please let me know if you get it fixed before I do...I'd love to know what's causing it.

Rob