I am having problems with the air blowing warm at all temps. It did this for a fe weeks then one day it started working again. Now it comes on sometimes and doesnt others. I THINK I got it to come on one time by smacking the HVAC control area and that made me feel like it was electrical, but really I have no idea. I couldnt get it to come back on like that yesterday for like 40 minutes then after I gave up for a while it decided okay I will let you have air now.

I tried to look in the haynes manual to see what wires it could be but its like a foreign language to me. Seems like the blower is normal, the controller is normal, the auto temp works when the air does want to blow cold, when working the temp settings all work correctly. Only thing wrong is when its not working the air comes out room temp. Heater always works. Its not the refridgerant because when it works it is ice cold like its supposed to be. Any ideas? Not sure where to diagnose?

 

My first start would be to check the charge. I believe there is a dual pressure switch on the big aluminum dryer/filter that should be somewhere near the radiator. It should be a 2 terminal connector. If the system won't run, disconnect the plug and probe the sensor with a multimeter on ohms. If the system is low on charge, this would be open. Ideally, if you also could probe it when it happens to be working, and this pressure sensor happens to be closed, its either low on charge or has a bad pressure sensor.

You could also just whack a can of 134a on it and see if that makes the compressor kick on. Refrigeration systems actually work better on low charge than high charge, so the fact that its blowing cold air isn't saying much.

 

Hmm anyone else? I have limited knowledge on these systems but from my research I am leaning towards a problem in the condensor or clutch. I hear the thing come on when I turn the ac on but the air isnt always cold. I was thinking the clutch isnt engaging right and therefore not compressing the air in the system.

I am not going to just throw more refrig. in because it seems to work fine when it does work it can go all day long if it wants to. From what I understand if it is fully pressurized adding more could lead to an expensive repair. Never get variation in temp just when it doesnt work it blows ambient temps.

I also read on some honda forums that the soldering behind the units can crack...

 

I had a similar problem and it turned out to be the compressor relay. This relay is located in the under hood fuse box which is in the engine compartment (page 245 in the owners manual).

There are three of the same relays in the fuse box. Temporarily you can swap the A/C compressor relay with one of the others to see if the compressor comes back on and operates like it should. But the other two relays are for the radiator fan circuit, so don't just swap them and leave it that way for a long period, the car could overheat without the fans operating properly.

They pull straight out and can only go back in one way. The A/C compressor relay needs a little coaxing to get out since those green relays are so close to it.

Below is a picture of the fuse box. The red circle is the A/C compressor relay, the yellow ones are the fan relays.

The part number is 39794-SDA-A03. They're about $25-30. The Acura parts dealer said they go through allot of these during the summer (he had 32 in stock).

Good Luck!

 

I completely agree with your reluctance to throw in some additional refrigerant. Especially because you say "...because it seems to work fine when it does work it can go all day long if it wants to". This strongly points to some other problem than low refrigerant. Given the history of compressor clutches, and what you describe, it sure sounds like the field coil is on its way out. But it's a relatively tough job to do so you probably want to be sure before you do it. Unfortunately sounds like your problem is intermittent and you will need to diagnose while it is failing.

Read the thread I linked below. It's where I helped another member diagnose an AC clutch field coil failure. It is a pretty common failure and relatively easy to diagnose. Much harder to actually replace. UA66's comment about the relay is a good one but if the relay is bad, and you swap it with another, you may set a warning code/light of some sort. So have an OBDII tool on hand (like an ELM327 and tourque app). Also, a new relay may fix the issue but if the field coil is dying then it won't fix it for long. How do I know about setting a code and the relay being a short fix? Been there, done that, with my Wife's CR-V...which is not significantly different from the TL with respect to clutch/fan wiring.

Thread about AC clutch --> https://acurazine.com/forums/3g-tl-p...engage-933847/

 

Thank you guys, this has been very helpful and gives me a few things to look at. Just picked up some oil and filter. Im going to take some time to do that and I will look at the AC too. Ive driven it more and it has failed more, so now the symptoms are more noticeable. I believe the compressor is not coming on now. Ive noticed that it revs normally now at all times. Versus the revs falling faster when the compressor is engaged. This is very noticeable to me since it is manual.

Hoping I can look at it soon, but not sure. Its probably going to rain me out tomorrow, soo maybe sometime this week. I will test the relays and go from there. I have taken off an AC compressor before. And every other accessory too, just not on this car. If it comes to it I can take it off, but I am crossing my fingers it is a stupid fuse/relay. I do have an OBD2 reader but I do not have a multimeter lol. Maybe ill just buy one, ill let you know what I find in the fuses and relays.

 

Check the AC compressor clutch. Had a similar issue on my 06. Changed the clutch coil and clutch and it has been great ever since. Did the job in the car, and didn't need to recharge the system.

 

Same here on my 04, the field coil and clutch components melted and it was a PITA to remove!

 

Shit, I bet that's my issue too...
it made a noise yesterday, started blowing hot...and I hear a noise when I engage it from teh engine bay along with a smell of something burning/rubbing...

Any DIY on that job? cs?

 

You can buy a new denso ac compressor on amazon for $200 and diy.

You'll need access to a ac machine to service it after installing a new compressor though

 

Yeah?
But there are supporting mods to go with it, right? Replace expansion valve and something else? Then recharge?

 

Im having the same issue on my 130k TL. I replaced the relays and clutch still not engaging. Tried to recharge but it didn't do anything. I took it to a local shop and they are saying the compressor needs to be replaced along with the expansion valve and drier, they told me to buy the "compressor kit" that comes with all these parts. Do we really need to replace all these parts when you replace the compressor?

 

I only had them change the compressor itself...$212 on amazon prime and mine fired right up and took the charge like a champ.