Now that winter is over, I'm in need of air conditioning. This started last fall. It seems that when my car heats up, the ac compressor clutch does NOT engage. The car air conditioning blows HOT. I have a few gauges that you connect to R-134A canisters, so I tried them on the low port. Earlier today, it was around 80 degrees and my car was hot and the clutch would not engage. I tried the gauges, but I don't think I'll get PSI readings when the ac clutch is not engaged. So then I waited a few hours and came out in the dark when it was 65 degrees. My air conditioning turned right on. I had the AC on Max, coldest setting, and recirculate. The AC clutch was engaged and I got readings from three different gauges: 22psi, 27psi, and 7psi. Not sure why they all gave different numbers. They were all low though. But the AC seemed to be blowing cold. I assume I should add more refrigerant? Will adding R-134A to the low line help the AC clutch engage?

I was thinking I should add refrigerant AND try to remove a shim from behind the ac clutch plate. I swapped the relays and nothing happened. I have watched videos on youtube, and it looks like I need to remove a 14 mm nut from the clutch plate, then remove a shim, then put the ac clutch plate back on.

Any tips and incite would be appreciated. I don't really know much about ac compressors, but I have watched a few YouTube videos to get an idea of the air conditioning system. Thanks

 

Last night I removed one of the shim washers from behind the clutch plate. When it's hot again, I'll let you know if the compressor engages. When the compressor wasn't engaging, it felt like warm air (not super hot) was coming from the vents. But the hotter it is outside, the hotter the air seems to be. Hopefully removing a shim fixed my issue. It's supposed to be cooler and rain all week, so I'll try to send an update next week.

 

@tech8 could you post the a/c troubleshooting section of the fsm?

 

Hi Chris,

I don't have access to every FSM. Also, I am not sure what year the OP's Civic is since they haven't posted that information.

 

I'm having a similar issue with my 07 dx and am looking for what could cause the a/c clutch to not engage.

 

I have a 2008 Honda Civic LX 4 door sedan, automatic transmission. I watched youtube videos. You remove the front passenger tire, then remove the plastic clips on the wheel well. Then use a 14mm socket to remove the nut on the ac clutch. Then remove one of the washer shims (I only had one on mine, so I removed it). So far, my ac clutch is engaging! My air conditioning seems like it could be a little colder though, so I'm watching youtube videos to learn how to use gauges to check the pressures and see if I need to add refrigerant.

There are many youtube videos on removing shims to get the ac compressor clutch to engage.

 

I don't need to remove a shim for no reason. I want to know why the clutch stopped engaging after the car sat for a couple months. My only suspect is a pinched line leading to the condensor.

 

I would check the fuses and relays first.

When you take the cover off the fuse box, check the MG CLUTCH fuse (15 amp) and the AC Clutch relay (snowflake image). Check those two. The relay very often needs to be replaced, and you can switch it with another one that's already plugged in to see if that fixes it.

This video might be helpful: