I have tried searching everywhere with no luck....hopefully someone can provide an answer...trying to avoid dealership.

Last week my radiator was leaking bad, so I replaced it...no problem.
The next day I noticed that my AC was blowing out hot air. I checked the relay and the fuse and those are both good. Both fans are running fine.
When I turn on the AC I can see that the compressor is not engaged.
When I check with gauges (car off) I get low side reading over 120 psi, and the high side at about 125 psi.
I have never added r134a to the system.

Any insight would be appreciated.

 

Check out this thread. https://acurazine.com/forums/3g-tl-p...engage-933847/ You may want to jumper the AC clutch relay to see for sure. Relays can develop a contact resistance of a couple ohms and that's enough to cause a failing field coil to not work.

Is it possible you did something to the AC compressor clutch wiring when you were replacing the rad? It would be kind of a coincidence for the AC comp clutch to die at the same time you changed your rad.. The die pretty often but the timing here is suspect.

 

I read that thread and tried to jumper. Car off....jumped pins 1 and 2 with wire. No sound of clutch engaging.
I tried this earlier (and again just now). I also tried identical relays (2 different) in that slot.....no effect.

I did a simple radiator replacement. Didn't go near the compressor other than to reconnect the wire to the harness attached to the fan bottom.

Would my pressure readings....low side high and high side low in any way restrict the function of the compression....ie....does an expansion valve failure restrict the compressor operation?

 

Jumpering the relay bypasses all the other stuff. Just to make sure. You have verified the fuse (#12, 7.5A) is good and that you have 12V at pin 1 in the relay socket. And that you are looking at the correct relay socket.

It still seems odd that it would fail the day after your other work without it being for some other reason. The symptoms point to a bad clutch/field coil. But I would check the wiring from the relay to the compressor to be sure. That's from the #2 terminal of the relay socket to the #1 pin on the connector on the compressor. The other thing to note, if you can, is are you seeing any sparks when you jumper/un-jumper the relay socket pins 1 and 2. That would tend to suggest there is current flowing in the field coil but the coil doesn't produce enough magnetic force to close the clutch and/or the clutch's air gap has increased (worn) beyond limits. It's a major pain to change the clutch so you don't want to jump to that conclusion without really good evidence.

 

I have 12.65V at pin 1.....crappy meter, so probably OK.
Fuse #12 is good....checked it and replaced it just in case...twice.
I am pretty sure that I have the correct relay....I have the service manual for my car....all 1500 pages.

I am thinking that it is the coil. I can get the stator kit for around $100. I don't want to do that job.
btw, I am also in CT. Do you know a trustworthy mechanic in the area? I have been doing my own work when possible b/c I have yet to find someone I trust. Dealership used to be good, but new ownership is all about making the most $$$ from the service dept.

 

You can buy a whole new compressor with field coil and clutch for about $200 from rockauto vs $500+ at a dealer. Any A/C shop can swap it out, but it seems that the low side has a very high pressure reading. Shouldn't it be around 100?

 

Yeah....the low side is really high, but I am not sure that it means anything since my compressor clutch won't engage....not sure that the number means anything.

I think that I am going to ride out the fall without AC and see how the car is doing in the spring. It is an 07 and has a ton of miles and a few lingering problems that could require more money than I am willing to put into her.

I have only owned Acura since graduating from college in 1988. If Acura can get the TLX paired with a good tranny or 6 sp manual I would do that, but right now I am looking at Lexus, Honda or maybe RDX.

 

Problem solved.
On a hunch I decided to jumper the wiring harness from the compressor clutch. Turns out that the connection in the harness itself was bad. Rewired and fired it up and now have A/C.
Thanks for the suggestions. Another day of keeping car out of the dealership.

 

Cool! (Literally) So it was the wire from the relay socket to the compressor connector? Glad it all worked out, It's really strange timing indeed but stuff happens.

 

in my 04 tl, there is a purple wire that runs down the passenger side of the radiator and has a clip/harness that can be unplugged. It deals with the ac compressor. Maybe that could have gotten damaged, not reconnected after the swap?