Darinm

Hi all, looking for some troubleshooting assistance. Last summer all was good with my A/C. Today i started it up just to charge up the battery and check things out. When i turned on the A/C, the compressor wouldnt kick in. Fan is blowing fine including high speed. I checked the fuse, which is good. I jumped the pressure switch, and nothing. I put my fluke meter on the A/C compressor and had zero voltage to the compressor. I used a jumper wire and was able to make the clutch kick in. So i'm trying to understand what/where sends the 12 volt signal to the compressor. Moving the slide switches from off all the way to defrost, all works fine. I'm assuming the A/C switch in the console is what kicks the compressor on and plan to pull that next and probe around with my fluke meter. I did notice the blower switch was warm but that may be normal.

Any thoughts on what i might be missing ?
Thanks in advance.

DUB

Verifying that you have voltage on the 'in' side of the pressure switch connector. Just because you 'jumped it'...does not mean anything unless it is getting power...as you know.

If you have a wiring diagram...verifying that you are getting voltage at the HVAC control head.

I know you checked the fuse...but did that also mean you check the voltage at the fuse also????

DUB

Darinm

Thanks Dub, yes i did have 12 volts at the fuse. I will check the voltage at the pressure switch tomorrow then if no power make my way up the circuit. it should be easy enough to reach under the console. I notice my switch was kind of finiky on the selection.

righthanddrive

It could be low on freon, which will prevent the compressor from coming on

Darinm

Okay, mystery solved. Should have seen it before. Voltage is good everywhere including up to the low pressure switch. First connections on the switch were dirty which is why nothing happened when i first jumped it. After cleaning the connections and jumping it, clutch kicks in. While it still wont turn on, i checked all the fittings and connections and they're all clean except the low pressure switch which is oily all around it. So im guessing that's where my leak is and will need re-charging. So looks like a trip to the A/C repair guy.

DUB

...but..... he jumped this connector and bypassed the high/low pressure switch(s) and it still did not work...as he wrote in his initial post.

DUB