A/C clutch not engaging

[LLCoolJosh]

I just replaced my ls3 with a 427 stroker and for some reason the AC hasn't engaged since.

I "charged" the low side with about 1.5 cans of refrigerant and the gauge on the can is in the red but I think that is because the clutch has not engaged. I have recharged the system like this 2 other times (cam install, turbo manifold ac line re-route) with no problem, the clutch always went to work.

The relay is picked when the ac is commanded on. If I remember correctly, there is + and - on the bottom 2 contacts and just positive across the top. I tried to measure voltage at the compressor harness with the car running, ac on max, and it was zero.

when I first started the car up I got the "ac off due to high engine temp" message because of my 160 thermostat. I edited the tune to ignore that code and re-flashed. Could the PCM still have the ac off or does it just pick the relay and the common is always on after the compressor?

the pressure sensor is brand new.

can someone point me in the direction of a wiring diagram?

thanks for any advice!

[houtx]

Having a similar issue to yours and was told by the shop that did work on the engine that ac controls are not working.

[Spurshot]

A/C clutches are pretty reliable. You can test it by removing the connector and putting 12v to the clutch. You should hear it engage just setting on the bench.

If the clutch and controls are good, jumping the high side pressure switch should engage the clutch.

The charging procedure I've been using is; vac the system, (engine off) open both valves on the gauges (low and hi) fill until the system won't take more or system capacity is reached, close the hi side gauge valve, start the engine, jump the hi side switch (clutch should engage), fill to proper capacity thru the low side, check pressures vs temperature.. Remove jumper.

[LLCoolJosh]

Do you mean that you are jumping the 3-wire sensor? Which wires?

[LLCoolJosh]

ok so I lied. there is 12 volts at the connector and HPtuners says the clutch is not off due to pressure or voltage and should be on. I guess the clutch is actually bad. Any pointers on getting the compressor out? looks like straight out through the front is my best bet..

[Mrgwrnch]

I had an issue like this and found the A/C pressures to high. There is a switch that cuts power to the clutch if to high.

[MrParker619]

Originally Posted by Mrgwrnch

I had an issue like this and found the A/C pressures to high. There is a switch that cuts power to the clutch if to high.

Forgive me for not knowing; I think I may have messed my system up a bit and that I may be facing a situation like yours (pressure now too high). Trying to learn how to debug and resolve this circumstance.

My A/C Compressor is not engaging. Did a little superficial troubleshooting: checked the fuse (good), I turned the clutch w/my hand to be sure it didn't lock up (good), and I think power is still running to it. The only thing that I can think of in my own version of root causing this is that I added some 'recharge' to the low-end of the line about a month prior. I live in the Bay Area and my car sits in the garage mostly(2012 SS).

If I somehow triggered that cut-off switch, what would be the road to redemption? How do I fix it?

[Bildo]

Bleed some off. Don't charge unless the clutch is actively engaged.

[Sleeper_Six]

There's a cutout function that prevents it from running if it's overcharged. Couldn't hurt evacuating it back down into proper levels and then seeing if you still have the problem.

[hamad88]

I had same issue, try to replace coolent temp sensor or check the connector