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Honda Civic Intermittent Air Conditioning

My 2nd car that I haven’t driven much over the last 4 years has had intermittent A/C. Now I need to drive it 400 miles a week for a new job so I need the A/C. Even though it is a 17-year old 1992 AT Civic DX it still gets 36 mpg on the highway so I can’t replace it with the Clunker deal.



Sometimes it blows cold for 10 minutes and then tails off and gets warm and humid. Sometimes it is cold for 45 minutes. And sometimes it is warm and humid from the get go. All these tests are generally at highway speeds on relatively warm days with the blower set high from the time I turn the car on; though, I’d say more often than not if it is over 90deg it usually doesn’t work at all.



I brought it to an independent mechanic 4 years ago and they recharged it and converted the refrigerant ($200+ for both). It seemed to work, but it was still intermittent but when I brought it back they said they re-tested a thermometer in the vent and it was fine.



Then last month I brought it somewhere else. They also recharged it ($100) and confirmed yes it is intermittent and it would require a costly compressor replacement.



Then yesterday I brought it to a Honda dealer and explained the symptoms. They called me at the end of the day and said they had found the problem. They said the fuse kept blowing because the compressor was intermittently seizing. $100 diagnostic fee. This explanation didn’t really make sense to me so I said on the phone that since it was working intermittently it couldn’t be a fuse problem because fuses don’t reset themselves, but she couldn’t really explain it any better. I picked up the car and did some electrical circuit troubleshooting. I confirmed the 20A field coil and condenser motor fuse was blown and replaced it with the spare. I then confirmed that compressor fan motor spins by disconnecting the relay and shorting the leads. I could also hear the clutch clicking when I did the same there; although, it did draw some sparks where I was inserting the jumper. At no point did the fuse blow. But then I replaced everything and started the car and turned on the A/C and sure enough the 20A fuse blew. I then tried checking the field coil resistance to ground. My multimeter is kinda cheap but it only registered less than 1 Ohm, so I think the Honda dealer permanently damaged the field coil.



I am at my wits end. The car A/C is not worth a $1200 compressor replacement. I know reman compressors are less than $300 but flushing and refilling a refrigerant loop I think is beyond my do-it-yourself ability.



Does it sound like the Honda dealer broke it completely, or is there some other explanation for the fuse blowing as I described that may be a cheaper repair?

Do I have another other options other than a full compressor replacement, and is there any way to get it done for substantially less than $1100-$1200.



Thx

Ed

I suggest you find an independent shop in your area that specializes in automotive cooling and AC systems. These folks are the experts, and have all the necessary equipment and knowledge to accurately diagnose and repair the AC system in your car.

In my humble opinion automotive AC is not a do-it-yourself thing.

If the refrigerant has been converted from R12 to R134a, and various mechanics have worked on the AC, there’s really no way to guess what might be causing the problem. You need an expert.

Understood. Unfortunately I’ve paid money to 3 ‘experts’ now and am actually worse off than when I started (going from intermittent to no A/C at all with the damage the Honda dealer did). If you have a suggestion in the Boston/Cambridge area I’d be happy to hear it.

A couple years ago I had the same problem with my 1998 Civic DX. It ended up being an electrical connection on the compressor. $1,200 later with a new compressor it works like a champ. Go ahead and bite the bullet. You know the new compressor will fix the problem since two A/C technicians have confirmed the diagnosis.

I think you are right. I was able to eliminate the fuse blowing that only started after visiting the Honda dealer service on Friday just by re-seating the two relays and replacing the fuse. I was then able to separately operate the condenser fan and compressor clutch using jumpers, and then successfully operate them normally with the car running and without blowing a fuse. But I measured the resistance to case from the compressor relay connector and it was less than 1 Ohm across the compressor clutch coil. By the manual it is supposed to be about 3 Ohms so it looks like there is some damage to the field coil. Visually looking down at it you can see the design is ripe for wear. The field coil leads are stretched tight across the top surface of the compressor with several insulation joints and I can see gaps with bare wire showing so I wouldn’t be surprised now if that is where the damage is. It’s pretty frustrating, though, that the recommended solution for a 1 dollar wire lead repair is a $1200 replacement of the whole system. If it wasn’t for dealing with recovering, flushing, and refilling the coolant when the compressor is removed to repair the wire I’d do it myself. Also it would be nice if I could get a shop to buy a $250 reman equivalent rather than a $700 Honda new compressor.

While you are at it, go ahead and have them clean the evaporator. After all this time without an in-cabin a/c filter, it could probably use a good cleaning.