I have an 03 EX-L with about 130K. I have a new problem. The AC works great as always until it doesn't. I've found it seems to stop working when I make any change in the temperature setting. (auto climate) I was driving yesterday with the AC working fine, turned the temperature up one or two degrees, and for the rest of the trip of about 30 minutes I had no AC. After it was parked for a half hour or so, when I started back up, I heard a definite clunk that I associate with the compressor clutch engaging and the AC worked great again. I stopped again for an errand and the AC worked when I left. Heading home on the interstate, the AC was working fine. I adjusted the temp a little and had no AC for the most of the rest of the journey home. I used the manual on and off button for the AC and at some point, it popped it back on.

Scouting around on the net, I find references to the clutch coil overheating / bad clutch relays / needing to replace the clutch assembly (and that some shops won't do that without replacing the whole compressor), etc. Seems to fit my symptoms of engaging but then no reengaging after cycling (caused by my change in the temp setting).

About a week ago, my alternator gave out. Apparently it was not charging enough to fully recharge the battery, but not charging low enough to turn on the warning light. The car stopped when the battery could no longer run the engine. I had a local shop I've used replace the alternator and that seems to work fine. Since they were there anyway, we replaced the serpentine belt at the same time. I bring this up because it seems awful coincidental that after 13 years, the unit right next to the alternator fails right after the repair.

So the questions are 1) is there anything they could have done that might result in the problem with the AC? The things I can think of include knocking a wire loose (doesn't perfectly fit the symptoms of being related to a change in temp setting), tightening the belt too much and putting strain on the AC
clutch, or ???. It of course could be a coincidence, but ....

And 2) do the symptoms indeed sound like a bad AC clutch?

Thanks

Tom

 

Did the problems start after the alternator was changed? Your belt is set by an auto-tensioner, so that is not your issue.

You haven't figured why the compressor is cutting out. First step is to check for HVAC codes. See this thread that is located in the common DIY thread on top of this forum. https://www.hondaaccordforum.com/for...-code-s-34589/

 

Thanks for the helpful response. I did the HVAC codes and nothing comes up. I held it for more than a minute and tried it twice. Stays blank.

Didn't know about the auto-tensioner. So obviously that's not it.

The alt replacement was about 2 weeks ago. I was gone most of this last week and it just started yesterday. So yes, within a week or so, but not immediately.

Thanks again.

Tom

 

Accidentally deleted the thread i referenced earlier and created a new thread. https://www.hondaaccordforum.com/for...94/#post370304

The first post was for a TSX, because I didn't have the accord shop manual. I wanted to make sure you followed the second post (now the first post in the link above).

 

Thanks. I had already checked for the codes, but did notice later that the link had stopped working. I did not get any codes or any indication whatsoever. I'm assuming you get nothing if there is no error code, correct?

I checked a couple of other things. I found a post that noted that the relay for the AC is the same as for another function (both in the engine compartment box) and suggested swapping them to see if it makes a difference. It did not. As per a question posed in another thread related to AC, the two cooling fans indeed to come on when the AC is turned on; the compressor just isn't kicking in.

Also noted that yesterday when I ran a quick errand, the AC worked, but was not nearly as cool as it normally would be. I'm wondering if the charge is low. To my knowledge, it's never been checked or recharged in 13 years. I'll get a bottle and gauge and check. I've read that a low charge can keep the compressor from kicking in ... is that true?

So far, here's my thinking. So far, whenever the car has been sitting for a while, the AC works upon startup. It seems to remain on for an extended period if I keep the thermostat low enough. If it cycles off for any reason, it will not cycle back on. It makes me think it is related to everything getting hot or perhaps it has to do with the system being pressurized as a result of the AC running. Does that make any sense?

Thanks

Tom

 

Update.

As expected, the compressor kicked in when I first started the car this morning. I drove for approximately 30 minutes with the temp set at 60 and the compressor ran the whole time. After stopping at a store, I switched the AC off and then back on. The compressor would not re-engage. I was in the store ~30 minutes. Compressor still did not engage for the quick drive home.

I checked the pressure using one of those gauges on a home-fill system. It reads in the "green zone" so I surmise that is not the issue.

Driving today I decided the system is running as cool as before. I had noted that yesterday it seemed to be not as cool. It was a hot car on a very hot day and a short drive, so I think that was the simple explanation.

I don't know what would cause the clutch to engage when the car has been sitting, but not re-engage after it has been running for a while. Seems like there are only a few things that would be different. 1. The whole engine and compartment would be hotter. 2. The AC system would have been pressurized by the working compressor. 3. The compressor itself or clutch could be hot or otherwise affected by running.

Any further suggestions? It may be time to take it to the shop.

BTW, I see online listings for a new Denco (OEM vendor, right?) compressor including the clutch for about $200-240.

Thanks

Tom

 

When the a/c is not working, is the blower fan still blowing hot/warm air through the vents? Is this a 4 or 6 cylinder? Does it have climate control?

Denso is an OEM vendor. I don't think your problem is with the compressor or the charge. This is an electrical problem.

When the a/c is not working, unplug the connector to the compressor and measure voltage to ground on the blu/red wire. Do this with the engine running and the a/c turned on (even if it is not working). Be careful working around moving parts.

 

I tried to cover some of this in the original post. 03 EX-L, 4 cyl. EX has the auto climate.

Everything works except the compressor does not kick in. Interior fans work, the two cooling fans in the engine compartment kick on and you can even feel the auto-idle kick up a bit. Starting up after the car has been sitting, everything works. But once I've driven a bit, if the compressor cycles off for any reason, it will not kick back in. The climate control continues to run normally, but the air is not cooled.

At this point, it seems there are two possibilities. Either something interferes with the electrical signal to the clutch, or the clutch is not responding to the electrical signal. We know the signal gets through and triggers the clutch to engage when I first start on a drive, so obviously the wires are connected et al. So it is something that happens as a result of having driven for a while - heat in the engine compartment, the pressure impact of running the AC, or ???

I know the compressor works since it does indeed cool properly when engaged. However, I'm beginning to think the clutch mechanism may be failing (I've read some other forum threads that seem to suggest that might be the case). Given the location, however, it seems impossible to replace the clutch without taking out the compressor. At that point, it seems reasonable to just replace the whole unit.

I will try to locate the connector to the compressor. When I did a cursory check the other day, I found the wire, but didn't see a connector. It just seemed to go into the compressor housing, but I didn't look that closely.

 

Thanks for the info. Just want to make sure I'm looking at the right wiring diagram.

The clutch could be replaced without opening the a/c system.

You could go through all of that work and possibly have a wiring problem upstream of the compressor. I think the connector for the compressor extends to the metal frame around the compressor/radiator fan.

 

Could be an intermittent clutch relay, faulty pressure switch, or a weak or intermittent issue with the clutch coil.

I replaced just the clutch and coil assembly on my '03 (coil shorted), with OEM parts, hasn't missed a beat since.

Shops are just lazy, takes a little more effort to do then just slapping in a remanf. compressor assembly.

These compressors are bullit proof, if the clutch coil turns out to be bad, replacement should solve the issue.