Troubleshoot car AC issue?

[thool]

My son has a 2007 Accord v6 and the AC doesn't work. By "doesn't work" I mean that the AC clutch is not engaging at all. I tried swapping the AC relay, jumping the AC relay, adding refrigerant (already has high enough pressure). The AC light comes on at the control panel, and the engine does sound like it is compensating for the upcoming load, but that load never comes. All fuses are intact, and I can see the relay does register 12 volts to call for AC when the AC button is pressed.

I noticed that the clutch plate that should be pulled into the sheave is not being pulled in. I tried to rotate it by gently rapping it with a piece of wood, but the plate did not rotate more than about 10 degrees. I'm not sure if this should move al all while disengaged.

Could the compressor be frozen up? Or possibly the coil, or the plate frozen? Anything else I can try before taking it to a shop?

 

[BillK]

Does it have "Freon" in it ? Most systems have a pressure switch that does not allow anything to operate if there is no pressure in the system.

That being said you really need to get hold of a service manual for proper troubleshooting procedure unless you just want to throw money at it.

 

[MattVette89]

This link has some troubleshooting:

https://repairpal.com/2006-honda-accord-24-ac-clutch-not-engaging-346

 

[thool]

Thanks. I can likely discount the relay swap since swapping them around did nothing. I'll keep scouring the web.

 

[GTA Matt]

Check for voltage at the compressor clutch connector, then put a compressor in it.

 

[thool]

Check for voltage at the compressor clutch connector, then put a compressor in it.

Never done this, but sounds like you're saying to disconnect the connector that goes to the clutch at the compressor, and see if it reads >0 volts. I'll have to crawl under there and see what it takes to get to it.

 

[GTA Matt]

Should have 12 volts with ac turned on. Usually you can get to the connector from the top, tight fit between the fans and the engine. Common failure for the clutch coil to go bad.

 

[MikeF2316]

If your compressor (clutch) is getting good power and not engaging, then you probably need a compressor. Note that some installations need a ground wire. Some compressors have a heat cutout on them, but that's not too common. If your clutch isn't getting power, then the interesting troubleshooting starts. Most cars these days have the compressor turned on by a body module, after that module gets OK's from the fuel computer (engine not too hot etc.), the climate control (driver wants A/C etc.) and the A/C itself (high pressure not too high, low pressure not too low).

 

[Milton Shaw]

I know GM cars have computer codes that will keep compressor from operating and not show up on the lights on the dash. So pull codes and make sure nothing in the computer is keeping it from operating. I had one car that randomly would set a code and not operate but still have pressures in the right range any time I pulled codes with a set of gauges installed. Never did figure out what was setting the code.