Expert: Sean Halliday - 6/3/2009

Question
QUESTION: On Sienna 2004 minivan stop working A/C. I did check fuses and presures in system - all OK. Pump start working when directly give power from batery. What do you think it could be? Sorry for my grammar misstakes.
Sergey

ANSWER: What pressure did you get at the low and high sides?Did you check the relay for the compressor?Low gas pressure will cause the safety sensor to activate and prevent the system from starting.

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QUESTION: I get from Wal-Mart a KIT and check. Gage show that pressure was good (by gage). I will check again today for sure. In fuse box has two similar relay, so I swap(exchange?). I have been in turn ON heat when A/C is on too because was smelly air come out.

Answer
This system will need to be looked at by a a/c tech.The Walmart gauge is not accurate.It is possibly the cut off sensor preventing the system from working as the gas is too low.These systems are best left to a pro as it is extremely dangerous to work on a/c, ( high pressure) if you do not know what you are doing.