[MW3Designs]

I was enjoying some nice cold A/C on the way to the baseball field, shut the car off a few minutes, when I started driving again no A/C. That was two days ago, and still no A/C. I do not have the flashing A/C light, and today when I put the gauges on I had a high reading on the low side. Not sure where to go from here…..

 

[repairman54]

When system is off the pressures equalize both sides.
Turn on a/c and see if compressor clutch engages and watch the pressures. If low side drops below 20-25 it will shut off compressor to protect the system. It will re-engage when low side rises up to around 35-40 as pressures equalize.
Since you have 100 in the system check for comp. clutch engagement when equalized, if not then power check at compressor relay would be my first step. Relay swapping with the same size relay is a quick relay check.

 

[MW3Designs]

That reading was with the engine running and A/C on. I pulled the relay and could hear the clutch engage when I put it back.

 

[MW3Designs]

Decided to investigate a little more tonight, looks like I might have something going on with the a/c clutch, I can get it to engage when I jump the relay (87 to 30) but I’m not getting a very loud click. Also, I got under there and inspected it visually, looks like something is up. As for the condenser itself it is not bound up and will spin freely. I’m going to see if I can find some parts from a local scrap yard to see if it is just the clutch.

 

[cintocrunch]

Yup bearing looks like toast... clutches don't engage well with grease on them. You gonna try to replace just the clutch/pulley or are you going to replace the entire compressor?

 

[MW3Designs]

Yup bearing looks like toast... clutches don't engage well with grease on them. You gonna try to replace just the clutch/pulley or are you going to replace the entire compressor?

Going to try just the clutch and see what happens.

 

[repairman54]

Yep looks like clutch is slipping by what looks like in the pictures of melted rubber dampeners.
Trouble is a JY one would need to be low mileage one. The clutch is a wear item and and as air gap increases in the clutch the less ''pull'' the magnet has to keep it engaged fully so they start slipping.
Clutch air gap info. - Measure the air gap between the pulley and the drive plate. Adjust the shims to achieve a 0.30-0.60 mm (0.011-0.023 in) air gap.

 

[MW3Designs]

Found a pretty new clutch at the JY, and swapped it out. Shims are good, clutch is engaging and holding strong when I jump the 87 / 30 on the relay, but the clutch will not engage with just the relay. I swapped relay with the horn and tested it, horn is good. Is there another fuse / sensor I am overlooking here, or could it be the compressor is not building any pressure? I don't want to throw parts at it, and find out the compressor isn't the issue.

 

[repairman54]

With it jumped and running are your pressures good on the high side and low side and cold air good? That would confirm compressor is good and with clutch engaging harness to clutch is good.
Need to check for power to the relays engagement coil at the fuse block.
If none then high pressure cut off bad is possible or HVAC module is not sending power to the relay.
I don't have a schematic for yours as you will need it to track down why relay has no power to it's coil.

 

[MW3Designs]

With the relay jumped, and clutch visibly engaged the high side pressure does not go up, it is equal with low side.

 

[repairman54]

Clutch engaged, center bolt turning then compressor is bad with no rise in high side or drop in low side.
System most likely will need to be flushed and new accumulator and orifice along with the compressor.

 

[MW3Designs]

Haven’t bought any of the new components to do the repair yet as I am still baffled as to why the AC light is on solid (not blinking like when low on coolant) and the ac clutch does not engage. If I jump the 87 and 30 for the ac relay the clutch engages fine. Put the relay in and clutch does not engage, don’t want to install a new compressor and still have it not engage.
I know there are two electrical connectors on the compressor, one for the clutch, but what is the other one for? Wondering if I have an electrical issue?

 

[srwa]

Haven’t bought any of the new components to do the repair yet as I am still baffled as to why the AC light is on solid (not blinking like when low on coolant) and the ac clutch does not engage. If I jump the 87 and 30 for the ac relay the clutch engages fine. Put the relay in and clutch does not engage, don’t want to install a new compressor and still have it not engage.
I know there are two electrical connectors on the compressor, one for the clutch, but what is the other one for? Wondering if I have an electrical issue?

2 connectors,or 2 wires? If 2 wires, what colors? 1 is probably the hot from #87 terminal when # 30 terminal is "closed" to # 87 of the a/c relay. The other is a ground. With everything off pull the a/c relay, jumper # 30 to #87 terminal. Check the voltage at the compressor, both wires.

Are the coolant fans coming on when the a/c is turned on and the clutch is engaged? If these do not come on the computer turns the a/c off. Vehicle a/c s will "typically"put a 2 to 3 ton "load" on the engine so it needs extra cooling. The computer controls it all. So, DO NOT jumper any terminal besides # 30 to # 87

Look at the diagram on the a/c relay, # 30 is always hot, battery voltage, and is "normally" open until the computer closes it to terminal #87.

 

[Troublesome3]

A faulty fan would cause high pressures on both sides if it's without airflow long enough. The Traverse cycles the fan on and of at idle and light loads. It's always good to know but I don't think the fan is the issue. In the picture low side was at 100 and high side was at 140 so not quite equal. To me it seems like your compressor went bad. Weird to go bad the way it did but, anything can happen. A faulty compressor is the only piece that will cause that symptom. Any other faulty components would still give you a variance in pressure one way or the other.

 

[MW3Designs]

I am wondering what the other plug on the compressor is for?

 

[repairman54]

It's either a high- or low-pressure sensor most likely. I don't have a schematic for your vehicle to check.

 

[MW3Designs]

I just want to make sure I check everything before throwing new parts at it. Would hate to install a new compressor / accessories and have the same issue. The fact that the AC light comes on as normal like the system is working and the clutch not engaging (unless I jump the relay) makes me wonder if something else might be going on with a sensor or component.

 

[srwa]

Evacuate the system, remove the compressor and take it apart. Then you'll know if good or bad .....or maybe "ugly".

If U do this , before taking it apart, remove the oil plug and carefully pour out the oil in a measured container.