location of a/c low pressure cycling switch?

Question

1998 plymouth voyager 2.4L,,4 cyl.--looking for the low-pressure cycling switch ,to keep the compressor running,while charging the a/c with R-134,,manual says put jumper wire ,to keep compressor running,,but not where the switch is---can anyone assist,,thank you

Answer 1

If I remember correctly, it's located near the expansion valve - on the engine firewall where the a/c lines go into the cabin. If you follow the lines off of the compressor, you can't miss it. Remember, the low side line is the larger of the two. That being said, you really don't need to jump this switch at all. If you've evacuated the system with a vacuum pump, it will take in enough 134a, with-out the engine running or compressor even on, to trip the switch when you start the engine. Just make sure your putting it in as a liquid when doing it with the engine off. Then, start the engine and a/c, and continue filling through the low pressure side until you've put in the correct amount for your vehicle (check the blue tag under the hood for the exact amount, but it should be around 2 lbs for a front a/c only system, and around 3 lbs for dual air) Just remember, if the engine is running, ONLY service through the low pressure port. Hope this helps, and good luck

Answer 2

It is on the expansion cylinder upstream of the evaporator.