# AC compressor problem, help?



## Jeffp_121 (Feb 24, 2018)

HI all this is Jeff, hoping for some help guidance. I have a 2012 Cruze LT with the 1.4L turbo engine. Last week I ran someones spare tire on the highway, hit the bottom passenger side and destroyoed the intercooler hose and sheared off the HP AC line going into the condensor (all refrigerant quickly leaked out of course, liekly along with some of the compressor oil). Intercooler hose was an easy fix to get driveable but its hot in SFL even in winter so I need AC. I replaced the entire HP/LP lines (the ones going back to the firewall, pulled vacuum for an hour, closed the gauge vales and let it site for an hour wiht no loss in vacuum, so I think I'm sealed up pretty well now. However I am not able to get the system refilled properly. With the refrigerant can I can get the LP side up to ~80 to 90ish psi, but even though I have the ac system on in the dashboard, the compressor never engages and I show no pressure at all on the HP side gauge. I did try jumpering across the AC compressor relay socket pins 30 to 87) but could not get the clutch to engage. However I wonder if the solenoid must be energized also with all the fancy computer controls on cars nowadays. I did see the wiring diagram on another but its not clear if the solenoid must be jumpered also, or for that matter why it is not engaging on its own. 

Any suggestions? Even though the system likely vented the refrigerant very quickly when the ac line was sheared off, I would think the low pressure cutout would have engaged to protect the compressor from continuing to run. 

Thanks all?


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## sailurman (Sep 29, 2016)

You are actually in the Diesel section


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## snowwy66 (Nov 5, 2017)

The low pressure cutout shuts the compressor off if pressure gets below 20 I think it is. Needs 50 psi to activate the compressor. 

If you're not reading on the high side. Check your gauges and make sure the high pressure valve is being pushed in for the gauge to read. If that checks out. I'd be examining the hose you just installed and the rest of your work.

And use a test light to check for power at the compressor plug.


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## Jeffp_121 (Feb 24, 2018)

Whoops sorry on the wrong section but thank you both! Snowwy, so I was def above 50 psi it actually got up to 90 psi when I was running the car with the r134 can hooked up, but am certain the compressor never kicked on. On the high side hose connections, for give me for a potential dumb question....if the compressor is not kicking on, would i read anything on the high side gauge? Maybe it would equal the low side reading at best?

On making sure the high pressure valve is being pushed in what do you mean? I have the standard set of gauges that hang from the hood that are loaners from autozone, and have it firmly inserted on the high pressure port. I assume I can't open the valve at the gauge else it will start sucking refrigerant into the high side also along with the low side.... 

Thank you!


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## snowwy66 (Nov 5, 2017)

You'll have equal pressure on both sides with compressor not running.

I don't know about autozone loaner gauges but both quick disconnects have knobs that turn clockwise to open the low and high valves. Counterclockwise to close the valves. Least they should.

The ac valves are Schrader valves. Exactly like tire stem valves. They work in the same manner.


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## Jeffp_121 (Feb 24, 2018)

Thanks again all. So I've found some time to perform some additional checks. For certain the AC compressor clutch is not engaging, however I can pull the AC compressor clutch relay in the underhood fuse block and jumper 12 VDC after which the clutch definitely engages. I've ruled out a bad relay (swapped with an identical relay). the wiring diagram I found shows the AC compressor clutch relay is energized by the KR75 Engine Controls Ignition Relay. I assume this relay does other things as well, but I can;t tell for certain which relay this is or any diagrams indicating whether it should be picked up anytime the engine s on, or if there are other factors. Also it wouldn't make sense to me the compressor is engaged anytime the car is on and running?


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