ac compressor not engaging

[icemetalstang]

My fuses are good
all electrical connections plugged in
ac selector switch good
all vacuum lines plugged in (behind dash and along firewall)
I havent had the chance to replace o rings that always go bad on ac qiuck connects.
The system is not charged. Will this cause the compressor not to engage?

 

[Hef5.0weisen]

there is a pressure switch you can jump to make it come on. From the front of the car with the hood open, the switxh is in the back left corner of the engine compartment. It is on the one of the AC lines, not hard to find, only one in the area. Pull the plug off, put a jumper wire between the pins, with that jumped and the AC ON, compressor should work....

had some pics of it a while ago (long gone), hope the description works for you

Mine was broke for a while, coolant leaked out over time, wouldn't come on. Jumoed it to ensure the comp still worked, then started looking for bad o-rings. Found bad ones on the lines right by the switch, replaced em (variety pack from Autozone) charged it up good for 4 yrs now.

Hope that helps, good luck

 

[HISSIN50]

As Hef said, check for power into the LPCS. If you have it but no power leaving the switch, then jumpering can tell you what's up. Only run it long enough to get a reading on your manifold gauges (if the system is low, you can burn up the system).

If you have power leaving the LPCS but the clutch doesnt engage, your WOT relay might have an issue.

 

[icemetalstang]

I will try it. Thank you

 

[BlownFiveLiter]

if the system is low, you can burn up the system

If the system is empty you will fry your AC compressor. There won't be any oil circulating.

 

[fish254]

the compressor will not come on if the system is not fully charged i had the same problem!!

 

[99FiveOh]

Yes, there's a low pressure cutoff swich on there for a reason. Only jump it to ensure your comopressor is ok and take a reading as JT said. A/C is one of the easiest systems on the car to diagnose and repair. I love working on A/C's!

 

[icemetalstang]

I bought a o ring kit from autozone and 4 cans 12oz r134a. Praying it works. I havent jumped switch as of yet. Making sure no leaks 1st. The price has definetly gone up on these cans. Im glad to have saved my handy dandy pressure guage.

 

[madams74]

Dont rule out the CCRM either.

 

[99FiveOh]

Until he has jumped the switch and verified the compressor works or not, we shouldn't go naming this and that as the culprits. There really isn't a problem right now since there's no refridgerent in the system.

Other than the low pressure switch going bad, these A/C systems are pretty durable! I'll bet when you charge the system it'll work just fine.

 

[madams74]

Until he has jumped the switch and verified the compressor works or not, we shouldn't go naming this and that as the culprits. There really isn't a problem right now since there's no refridgerent in the system.

Other than the low pressure switch going bad, these A/C systems are pretty durable! I'll bet when you charge the system it'll work just fine.

This and that? Getting the freon in the system is fine, but the circuit still has to go through the CCRM. Naming off a component that COULD be an issue after it is charged, is hardly a reason to tell people we should not go naming possible things as culprits. Its not like were confusing him or anything. Relax man.......

 

[.95stang.]

my ac compressor is still not engagin. please help

my fuses are good. there is voltage in both pressure switches. the green one on top of the air cleaner and the one on the accumalator. i tried using a jumper wire to the switch on accumalator. compressor did not engage. system has one can of freon. i got power and ground from compressor connected directly to battery while still plugged and compressor engaged but why not on its own?

 

[99FiveOh]

Did you make sure the A/C switch inside the car was turned on before you jumped the low pressure switch?

 

[.95stang.]

yes i turned on the car and turned knob to max a/c. i checked for voltage on both switches. marking 12v. fuses are good.

 

[HISSIN50]

Check the WOT relay in/outs.

 

[.95stang.]

i was reading about those wot. still have no idea what they are or where they are at sorry can u help me out?

 

[HISSIN50]

The relay is in the CCRM. I don't have a pin-out handy however.

 

[fordtech28]

I think your still too low on freon for the compressor to even engage

 

[HISSIN50]

It would engage if low on freon since he is jumping the LPCS.



Check CCRM pin 23 (blk/yel) for 12V when the AC should be on.

If you don't have it, check CCRM pin 22 (pink/yel) to ensure it doesn't have continuity to ground.

CCRM Pin 21 (DG/O) should show 12v

Make sure CCRM Pin 16 shows continuity to ground (less than 5 Ohms).

 

[.95stang.]

ok thanks alot guys ill try that hissin. and ill let you know if i did or not find voltage.