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Hi,
My A/C worked great at the start of last summer, but towards the end it started to blow hot air. I've finally decided I want to try diagnosing it. I've run the HVAC self-test and it doesn't flash any codes. Both fans on the front of the car work, but they don't turn on when the A/C is turned on. I don't really hear any tonal difference when the A/C is on or off, so I'm not sure if the compressor is even kicking in. Any ideas? My memory of last summer is a little hazy for timeline but I did have the center console out to install an aftermarket deck... maybe I knocked a connector loose?
I don't know. Would there be an adequate way of testing without buying a special gauge? I may be able to borrow one from a friend. Something like this?
You need an A/C manifold gauge set to test, my local parts store rents this tool. Just put down a deposit, return the tool when you're done and get everything back.
You need an A/C manifold gauge set to test, my local parts store rents this tool. Just put down a deposit, return the tool when you're done and get everything back.
Oh, that's a good reminder. Some stores in my area do that too. I'll see if I can obtain a gauge one way or another.
Even quicker, test ac pressure switch, if you don’t get continuity then you go get gauges to verify system pressure.
In the unlikely event you have normal pressure then you know you need a new switch..
We don’t see a lot of DIY ac repair in this forum for various valid reasons, but typically the purchase price of a low price dual stage vacuum pump and gauge set plus the dye and ultimately bad part and always new drier is less than a trip to local garage to do it. Second time you use the pump and gauges to do a repair you really start saving the $$$
I tested the AC pressure switch for continuity with the key OFF and got nothing. I jumped the switch, started car, and heard a hissing noise coming out of the vents, didn't want to run it too long without knowing if that was going to be damaging. Do I need a gauge that tests both high and low? Or would one used for filling the low port be acceptable?
That hissing could easily be sound of air being pumped around instead of refrigerant, your compressor will overheat and burn out very quickly without fluid so bypassing the switch for more than a testing moment will cause damage.
Now your in leak detection mode. Hopefully it’s is just a hole in the front coil which is very susceptible to road debris puncturing it.
If you think a good mechanic is expensive, try hiring a bad one
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Re: 2001 Civic LX - A/C blows hot air
When he said coil he was referring to the condenser. The thing that resembles a radiator out in front of the actual radiator.
Because of location, it's susceptible to rock and road debris damage.
But it's not the only place a system can leak.
Most of the time when an AC system leaks, traces of oil are left behind and dirt may stick to the oil spot....so check the condenser area, and also follow the AC pipes and other components all the way around the engine compartment and look for the evidence of leakage.
I have a 2008 Honda Civic LX- First my air was working then stopped the blower wasn't blowing so I got new relays, got a new blower motor and resistor. A/c now blows hot air,
and when I turn the **** to off position it won't shut off and keeps blowing hot air, What could be the problem?? Please help
I pulled out the relays and the blower turned off, one of the relays was hot to the touch. When the relays are plugged in I turn the **** to off position and doesn't
shut off keeps blowing hot air???
Re: 2008 Civic LX - A/C blows hot air 
