A/C issues -- couple of questions

[TxGator]

2006, sport, 3.7 V6, Manual, 28K miles

A/C doesn't turn on, specificallt A/C Compressor clutch doesn't engage.

A little back history is recent A/C zone issues -- intermittent.
2 or 3 days of intermittent cooling over the past 4 months
Accumulator/dryer was frozen like a popsicle during one of the intermittent zone issues (noticed while I was troubleshooting)

Took it to a mechanic who has his own small garage. He put a vacuum on it and said the pressure was ok and it was only slightly low on freon. The label on the inside of the hood says 1.12 lbs and I think the machine was reading about .9 ozs. He checked for leaks and could only find a very small amount directly on the bolts which seal/attach the dryer. No leaks on any of the weld points or lines.

He tested every fuse and all were OK.

He jumped the power cable at the accumulator and the clutch still would not engage. He repeated this after adding some freon.

He confirmed power to "both sides" of the compressor. It was OK.

He tapped on the clutch pulley. It wouldn't kick-start it.

He feels that the compressor clutch (at least) is bad. And recommends replacing the entire compressor.

I think he's right, unfortunately, but wanted additional opinions. Is there anything else I can test?

How about the AC clutch relay? Could that be bad? It's cheap and I could replace it myself. But he drained all the freon. So now the compressor won't come on no matter what, correct? How can I jump the dryer to force it to come on, just as a test? If I can't do that? Which is the high and low pressure side? Or, in other words, which port would I use to add freon?

Thanks in advance....

 

[jnaut]

You could have multiple problems-- a combination of all of the above.

Could be the clutch, could be the relay, could be something in the compressor.

The fact that you're low on refrigerant at all suggests that you have a leak. AC systems are closed. So if they're low, it's leaking somewhere.

 

[family KJ]

You could have multiple problems-- a combination of all of the above.

Could be the clutch, could be the relay, could be something in the compressor.

The fact that you're low on refrigerant at all suggests that you have a leak. AC systems are closed. So if they're low, it's leaking somewhere.

X2 in all that...I just went through this, but I have a 2 year old compressor (hoping that was not the problem)... I tried to put some refrigerant in and it did not take any (good thing) So the last was the low pressure switch which was suggested by TJKJ and that $15 part was the fix. No more freezing up.

 

[kb0nly]

You can bypass the low pressure switch, but it sounds like the guy already did that when testing it.

Best bet, bad clutch coil, that has showed up a lot. The clutch itself can be replaced but its a heck of a job, since the system is already empty your better off buying a replacement compressor and replacing that yourself, then take it back and have him put in the right amount of oil and freon and recharge it.

FYI... If you disconnect the wiring at the compressor you can apply 12v and ground and see if the coil and clutch actuate, don't even need the engine running, i've done that many a time to check a junkyard compressor with a small battery and jumper leads. If it doesn't click as the coil tries to engage the clutch then its shot.

 

[gijoe31484]

i just got a whole new compressor from jeepair.com for about $250. once the R134a is added in sufficient amount it works like a charm.