8th gen Civic AC problem

[GeX]

The AC abrubtly stopped working in my 2007 Civic. I didn't think it had run out of gas as this has happened before and I noticed the AC decline as it slowly leaked away. I've seen that a common issue on these is there is a relay that controls the AC compressor clutch can fail.
I haven't tested this relay (yet) as I can see the AC condenser clutch engage and the first stage fan kicks in. If the relay was faulty, this would not happen.

I next suspected the mixer flaps / air diverter valves, so scanned it and got



Thought I was onto something there, so stuck my head in the footwell to watch if the valves were moving properly when changing from hot->cold->hot->cold and found that they were. I also noticed the trim wasn't clipped back on properly around the access to them. I cleared the faults and ran a module self test where it actuated all the valves throughout their range.. and it came back with no faults. Suspect those flaps have previously failed, been replaced and the code not cleared.

This put me back onto suspecting no gas (but confused as to why the AC compressor is kicking in as surely a low pressure switch would inhibit this) so booked it into to be recharged.

It's been recharged but they couldn't get it to blow cold air, the gas was low but not empty and no leaks were detected when filling it. It's holding pressure (else I guess they'd have had to have drained it).

So this has put me back wondering if the compressor is dead, it spins but perhaps it's failed inside. Does this seem logical, or is there something else I should check before getting that replaced?

 

[dacads]

Sounds like you’ve done a good diagnosis yourself, I have a similar issue with my 2009 Civic. Took it to a so called AC Expert who suggested if I want cold then buy a fridge but then concluded it could be the compressor.

Also the issue is more apparent over certain outside temperatures if that makes sense I.e. anything over 20c outside it blows cold for a few seconds. If it’s mild outside then it blows cold fine.

From what I remember for replacing the compressor it would have been £5-600 all in which is more than I’d be willing to spend tbh.

Would be good to see what the issue was if you sort it.

 

[GeX]

Helpful of them.. I'm used to the AC blowing so cold it hurts my hands after a short while!

Compressor is £187 from https://www.onlinecarparts.co.uk/ca...hback-fn-fk/19241/10454/compressor-parts.html - so hoping it shouldn't be too expensive to have replaced (or if I get silly quotes, I'll do it myself!)

 

[dacads]

Yeah exactly I know what AC should feel like, I’ve been in tropical countries with AC working ice cold so no reason for it not to be doing the same in England!

Also the relay should be in the engine fuse box IIRC. There’s also a fuse

My car is quite high mileage so only worth a couple grand, still spent a few hundred on it recently, brakes, suspension, tires etc.

Think I’ll just save up and get a different car in the future with working AC.. touch wood

 

[Dup]

Common issues are the relay which you can just remove and bridge two of the connections to bypass and see if it engages and the clutch shims (https://www.coxmotorparts.co.uk/hon...ir-conditioner-compressor-shim-set-2006-2011/). Both of these mean the compressor pulley wouldn't be actually spinning (well the very outer part anyway) and it sounds like yours is definitely engaging. Although it wouldn't throw a fault if those were the issue IIRC.

Does to me seem like a dead compressor from what you've said, I'd expect pressure switches etc would indicate an issue. A/C always seems like voodoo to me and needs expert attention. Most garages just throw parts at the problem.

 

[casper_uk]

Relay, shim on the compressor, dodgy compressor or dodgy condenser are the normal failures if your gas levels are ok.

https://www.civinfo.com/threads/ac-compressor-overhaul-shim-replacement.108072/ Will give you info on the shim, check to see if the clutch is actually engaging the pulley (best check when cold and warm).

Dodgy compressor will need replacing, easy enough to do from the bottom if you remove the bottom tray. Dodgy condenser is probably due to stone damage etc. Again, not a bad job if you have small hands and can be done without removing the bumper. I need to replace both my condenser and compressor, but it's just not worth it for the age of the car now.

 

[GeX]

Thanks, I’ll look into shims next. I just did a quick check that the clutch looked to be engaging (to confirm the relay was working) before moving on. It had a new condenser a couple of years ago and it looks intact still, if it was damaged I’d expect it to not hold pressure.
Car is getting on but I’m not living without AC when the kids are in the back!

 

[dacads]

interesting about the shim, that would save a few bucks haha

 

[The-Plethora]

Had the same issue on mine. Took it to an AC place I have used before and they said its probably the condenser as they have done several on those. They topped up the AC and put dye in it and it lasted about 2 days but like you the leak rate was so low they could not detect a leak, nothing around the compressor and yep it was the AC condenser. Got it replaced and no problems since.

 

[GeX]

Yeah exactly I know what AC should feel like, I’ve been in tropical countries with AC working ice cold so no reason for it not to be doing the same in England!

Also the relay should be in the engine fuse box IIRC. There’s also a fuse

My car is quite high mileage so only worth a couple grand, still spent a few hundred on it recently, brakes, suspension, tires etc.

Think I’ll just save up and get a different car in the future with working AC.. touch wood

Does the low speed fan kick in as soon as the AC is enabled on yours, on my other car it only comes on if the pressure in the AC system reaches a certain level.

Had the same issue on mine. Took it to an AC place I have used before and they said its probably the condenser as they have done several on those. They topped up the AC and put dye in it and it lasted about 2 days but like you the leak rate was so low they could not detect a leak, nothing around the compressor and yep it was the AC condenser. Got it replaced and no problems since.

The condenser is relatively new, and even after being freshly gassed they couldn't get it to go cold - so I don't think it is that. Same question re the low speed fan though

 

[Jokester]

Never knew about this, my AC failed on my Civic years ago and I never bothered fixing it - but I'll do a bit more investigation now.

 

[dacads]

@GeX yes a fan kicks in

Also I did pay for a regas which only lasted a day or two but there was
no leaks from what the engineer could see / hear

 

[GeX]

Turns out it was the relay.

After getting it regassed, I went back and checked the clutch again. Couldn't see it engaging at all.
Ordered a new relay as they're only £6, fitted it and the clutch engages now.

When it was failing I felt like it was intermittent, and I guess when I was checking the clutch it was intermittently working. I've rechecked the videos I took at the time and sure enough, the clutch was engaging.