trussman

AC will not come on. The light illuminates on the dash and the fan works, but the compressor does not kick in. Took it to a local shop and the mechanic said the unit is charged with freon, however there is no fire (I'm assuming he means electricity) going to the AC. Any help would be greatly appreciated.

Thanks,
Stephen

RemyL31

iTrader: (1)

Check the voltage at the compressor with the a/c button on..if none, put a jumper wire to it to see if it kicks the clutch in

You must have a break in the line somewhere...you'll have to trace the lines to find it...

danpie01

I have a 07 Honda civic LX and my AC just quit working. The clutch on the compressor doesn't engage. Any new developpement on this thred

Thanks

98blaster+4

mine is doing the same kinda thing......turn the ac on and it doesnt kick the fan on or engage the compressor......as told that if you have low or high pressure in the ac freeon department it wont kick it on to avoid damage to the system.
i noticed while checking things out that one of the fill caps had been leaking a tad , the undeside of the cap had an oily residue on it.
havent taken it to get recharged due to lack of funds. but im certain recharging the system will fix it

08EX

If system pressures are below 28 psi or above 450 psi, the compressor won't turn on. Given the leaky AC systems these cars seem to have, low pressure is most common.
You also have to check the thermal protector on the side of the AC compressor.

Check the thermal protector for continuity. If there is no continuity repalce the thermal protector. NOTE: The thermal protector will have no continuity above 122 to 128 °C (252 to 262 °F). When the temperature drops below 116 to 104 °C (241 to 219 °F), the thermal protector will have continuity.

pl747

Same thing here with a 2006. Plenty of refrigerant at a little over 100# static pressure not running but the compressor won't kick in. I see the high pressure switch but does any know where the low pressure switch is? Is the drier and switch up under the front plastic where it's almost impossible to get to?

ezone

Without looking at references....I believe that switch covers both high and low pressures. Has continuity when pressure is between 28 and 450 PSI, and open circuit when outside those ranges.

When you turn on the AC system and the compressor does not engage, do the radiator fans kick on or do they stay off? (you may need to watch them, they aren't always loud on low speed).

HTH

pl747

The drivers side fan kicks on when the air conditioner switch is turned on. Which fuse is for the air conditioner?

ezone

That ain't right, I believe BOTH fans should come on when the AC is turned on....You may have wiring problems or something.

The fact that a fan turns on means the PCM has allowed the AC to operate. The PCM has turned on the clutch relay and the fan relays together, so the compressor SHOULD be operating.
I would start my tests at the relay for the comp clutch to see what the next step would be for me.

A wiring diagram and a test light would be my complete arsenal of diagnostic equipment at this moment.


Engine compartment fusebox: Fuses 6, 7, 9, 11, 20,
fuse #20 is for the compressor.
6 7 11 are for the fans
9 is for the inside blower fan


HTH

bdby1977

i have a 2007 civic ac quit now wont fire it will turn over but no spark any answers to this prob plz help

ezone

Check for codes.

Scruffy

I have a 2006 Civic with the same issue. Has anyone found a common thread causing this? Is it a possible grounding problem?
EZONE...I have done all the verifications you have mentioned. The fans both run, the fuses are good, relays have been swapped out, pressure checked...any new ideas????
The HDS has not been done. Haven't taken to dealer to verify...yet.
Any advise??

ezone

06, fans run with the AC turned on but the compressor clutch doesn't come on, that means the HVAC controller is good, the MICU, and the Freon are all fine.

You don't have a scanner to see if the PCM is turning the AC relay on.

I would start my tests in the AC clutch relay socket as has been described in other threads. Knowing which single terminal of the 4 isn't right will lead to the correct diag much faster than any other guesswork.


https://www.civicforums.com/forums/1...ml#post4608910

This post has the funky generic diagram of the terminals in the socket. Peruse the whole thread, but the checks at the relay socket are in there somewhere. Also note there are multiple posters asking questions and I get confused easily.


Another thread.
https://www.civicforums.com/forums/1...-civic-si.html

Search. I have posted an awful lot here.
Figure out how to check resistance of the clutch coil. 2-5 ohms IIRC.