Rep Power: 176

Neighbor kid asked me to help him put freon in his A/C system. I have a 2001 Civic and the drier is right in front of the firewall and we can get to the low pressure switch no problem. Just giving his car a quick look over, I could not find where his low pressure switch is. His car is a 99 or 2000. I told him I would help him tomorrow. Please tell me where the low pressure switch is located.

 
Rep Power: 518

It's on the drier bottle, right about under the power steering reservoir.

Ohm check it or something first, if it is open circuit then it's probably leaked out the freon.
If it's closed and shows continuity, it's got freon in it and you need to look elsewhere. .......like the clutch air gap is too wide or something.


The low pressure switch will turn on and let the compressor run once the system has about 28 PSI in it. That should happen shortly after letting the freon can flow into it, really no need to jump the wires there IMO but it might speed up the process.
I never jumper them when charging a system....

and on newer cars you can do a lot of expensive damage if you try to jump wiring for a pressure sensor.