A/C Compressor not engaging

[blacksport325]

I've decided to dive into another issue, my AC compressor isn't engaging when pushing the AC button. It's been changed over to R134a refrigerant by the PO, when I try to fill it the pressure will rise on my gauge but it looses all pressure within a few minutes, could this be because the A/C comp. isn't engaging? I have tried a soap/bubble test for leaks and couldn't find any, it might be time to try a UV test as well. I may take a look at the A/C today and see what the clutch looks like if its easy to get to...thanks in advance.

[jlevie]

The compressor might not be engaging because the charge is gone. Check continuity on the low pressure switch. If that switch isn't closing the compressor won't engage. The switch could be bad, but more commonly the cause is low charge.

[b*saint]

The pressure will rise but once your compressor kicks on it will go down. If you don't have enough freon in the system, it will go down to 0. It probably needs a charge.

[blacksport325]

I'll look into it today, i've charged it a few times and it keeps falling to 0 so I must have a leak somewhere, i'll check the low pressure switch.

[Huff]

It sounds like you have a leak for sure. Use a UV test kit for sure.

[CorvallisBMW]

+1 on leak