SHaFT7

2004 TL 5AT

We had our first semi hot day yesterday and I found that my A/C is blowing hot air. Being that I had the car refilled last year, I was a little ticked that it leaked out again. Also, I had had the A/C clutch replace under warranty with about 43k on the clock in 2007 (91k now in 2010, 3 years later) so if it was that I was also going to be ticked

Took it to my local shop, he said it was the A/C clutch again. He said that when the car is cold, it engages, but once it warms up, the clutch won't stay engaged, it pops in and out.

Took it to Acura, they said it wasn't the clutch, it was the relay assembly that the relay SITS in that controls the clutch. They want 500 and change to fix it. I was thinking that replacing a relay assembly wouldn't be all that hard, as I've done everything myself on a car before except for rotating assembly work.

Any one have previous experience with this? testing procedures, part numbers, etc?

eg5

iTrader: (4)

find the a/c clutch relay, pull it out. find another same relay, swap, see if clutch engages and dissengages automatically

SHaFT7

i will try that, but acura says they did, and that didn't help, that it's the connector box that the relay plugs into that's the problem (the connector didn't show voltage when it was supposed to.)

SHaFT7

specifically, this box:

38200-SEP-A04

RACINGHART03

iTrader: (2)

Not buying it. Prob low on freon.

SHaFT7

nope. the first shop evac'd the system, and it was only 2oz low. this is a 24oz system, and 2oz low is not enough to trip the low sensor. they completely refilled, and the problem was still there.

i did some more testing yesterday. on my way home, the a/c worked for awhile, then i could tell that it quit working. I pulled into the driveway, left the car running, popped the hood, and pulled the a/c clutch relay. I popped in a jumper wire, and the clutch kicked in and the a/c worked great. I popped out the wire, popped the relay back in, and it continued to work.

doing the testing from the service manual, I've been able to check everything but the ECU pins themselves, and i somehow doubt that that is the problem...

SHaFT7

ok, more stuff found out today:

got in the car cold (had been sitting for a full day). got on the highway, A/C worked great for 20min. then it cut out, you could feel the air coming in had full humidity, and was starting to warm up. 15min later, it cut back in for 5 min and worked fine. then it cut out again. when i got to where I was going, it still didn't work.

I left the car running, popped the hood, and the clutch on the A/C is not turning. opened the underhood fuse box, and pulled the A/C clutch relay, and put in a jumper wire, no dice. I took a measurement on pin1 of the relay 4P socket vs body ground and have full 14V.

ideas? it seems that I have a heat-related voltage issue....

SHaFT7

no one has any ideas?

eg5

iTrader: (4)

replace the ac coil(id replace the clutch aswell)
find the harness that comes out of the compressor, unplug it, (be very careful) check for battery voltage at harness side. yes car on ac on watch out for the fans. if you get battery voltage(please note bat voltage will not be there all the time, as you know the ac clutch is not engaged at all times.
good luck

SHaFT7

I had the clutch replaced under warranty 2 years ago. I'll check it, but i'll be highly surprised if it only lasted 2 years. My next step is to check that heat isn't causing a connection issue on the wire that connects the clutch to the relay box.

dcdeep

mine worked today until the temp hit 85 and cut out, I have a fully charged system, so I am interested to see how you make out.

SHaFT7

the rain has been nonstop, and i haven't had a chance to test. gonna try for this weekend.

SHaFT7

ok, i think i've narrowed it down to the a/c clutch. i unhooked the blue/red wire that triggers the clutch and tested continuity back to the relay box, and it was good.

I tried a jump wire directly from the top of the relay box, where I tested for positive voltage and have it, and still nothing.

I put the relay back in, and tested for voltage at the a/c clutch, and I have it when the a/c is turned on, so it looks like the relay box is actually ok, unlike what acura said. (everytime i've tested, it I have voltage, when i shouldn't if it was bad.)

so, it does look like right now that the a/c clutch has a heat problem,. when the car is cold, it works great, as it heats up, it cuts out, then will cut in later for a bit, and then back out.

sad thing is, I had this replaced 40k (3 years) ago, so it's strange that is already bad AGAIN.

SHaFT7

going to test the compressor clutch field coil in the morning, after the car is at the requisite 68 deg for proper resistance testing.

eg5

iTrader: (4)

cool. perhaps the clutch/pulley distance becomes too great when it reaches a certain temp. causing no/little contsct when the coil is energized.
try this out, on a cold engine grab a regular sized business card and check the clearnace between the clutch and the pulley. you should have a slight drag.
yes i know this isnt the actual way acura guages their measurements but id figure its something most people commonly have laying around.
are you going to replace the coil/clutch(pulley) assemblies yourself?

SHaFT7

tested the coil on the engine cold, 4.5ohm. the range is 3.9-4.3ohm at 68 deg (it's probably 72 in the garage right now). so i'm figuring that when the engine is cold, it's fine, but as it warms up, the resistance goes up, past the point where the coil can engage the clutch.

To reiterate, the a/c is perfect on a cold engine, no weird noise, no cut in and out, nothing. it's only once the engine is warm does it start acting up.

once i get back from the store, i'll measure resistance again, and i expect it to be much higher than the tolerable range. (however, i have no idea the tolerable range when the engine is hot, but it should be way way higher i wouldn't think)

SHaFT7

oh, and yes i'm gonna do the coil myself. looks like i just need to pop the belt, rent a a/c pulley tool, pull it apart, and pop in the new coil (taking care not to lose any shims )

found it online for $76.76 from two different places.

rbf351

if you need i am selling a brand new clutch coil, i thought my coil was shot, and it ended up being the compressor. Since i did install it on the car, and ran it for a few seconds i am will to take a hit on it, and sell it for 50 bucks.

just a FYI you can do all the work with compressor on the car, this way you do not open the system and do not lose any refrigerant. it takes a little patience since it is very tight, but it is doable

SHaFT7

i'll take it, you take paypal?

rbf351

yes I do paypal@rbf351.com, I will inclue everything Acura gave to me with it (shims, harness, and spring clips) also I do not accept returns

rbf351

also since u ate using paypal please add the 3 percent fee

eg5

iTrader: (4)

I don't know why but it makes me feel warm inside when people diagonse their problems and solve em. Guess its that do it your selfer attitude.
Good luck and post updates.
...like stated above ac compressor doesn't need to come off. I'm sure u have plenty of specialty tools so it'll be a breeze.
(Gotta love those angled snap ring pliers)

SHaFT7

yeah i have 'em

so, what did you remove for easy access to the compressor?

(also, paypal money sent, thanks!)

rbf351

same steps as if you are taking the compressor out of the car. remove the belt, remove the alternator, then take out the 4 bolts that hold the compressor from the car, and let it sit on the frame.

from there take off the passenger wheel, remove the plastic from the wheel area

you'll be able to move the compressor around a little to get on the clutch removal tool, then if you have the correct snap ring pliers you will be able to pull those as well.

SHaFT7

cool, thanks. i'll keep you guys updated once i get started. may even do a tech article on it

rbf351

please take a look at the PM i sent you

SHaFT7

just watched a video on that power probe 3. I will purchase one immediately. talk about awesome

SHaFT7

new field coil installed. Full write up with pictures coming in the morning!

everything looks to be running great now! $50 fix sure beats a $950 fix!

SHaFT7

guide is here:

https://acurazine.com/forums/3g-tl-problems-fixes-114/c-field-coil-replacement-guide-772614/

SHaFT7

so i'm back again. this morning, my AC worked just fine. now the clutch straight up won't come on. I did all of the tests like before. the only one that's weird is the field coil resistance. i'm currently in the 200ohm range, but the engine is still fairly hot. acura only gives specs on what the ohms on the field coil should be at 65deg F. anyone know what it is when the engine is hot?

also, do you think that possible I just need to reshim the clutch? or does this sound like a field coil? (which means the new one I installed lasted 1 year...)

SHaFT7

ok, testing this morning, the resistance is 4.2ohms, which is right in range. i'm assuming once again that as the field coil heats up, the resistance goes up out of range. the a/c this morning is working perfectly fine, delivering 40deg air. maybe this field coil just gave out early...

SHaFT7

ok, ran it for several hours today. on the third trip (highway) it gave out. I left it off for a few minutes and then turned a/c back on, and it came back and worked for the rest of the trip. most strange. i'm still thinking field coil, but I don't like that it's being intermittent.

teejnut

SHaFT7- how did you test the resistance on the field coil? I followed the FSM but just to confirm I did it right.

"I tried to check the field coil resistance but didn't get any reading on my multi-meter. Not sure if I'm doing it right or not... I turned multi-meter to ohms 200 setting. Connect one side to plug coming out of compressor and another to the body of the compressor. It doesn't read anything. Am I doing it right?"

Here's my problem thread: A/C - low & high side reading the same PSI - AcuraZine Community