Air Conditioner Problem

[myowneq]

Hello Everyone,

I was minutes away from selling my car when the buyer noticed that while the AC said it was on, it wasn't blowing cold. Couldn't tell in the shade, but in the sun, noticed it right away.

So I've been working on it and here's what I have. It's an issue with the relay. The relay is good. I've verified that by swapping it with a known good one and putting it in something else's slot. The compressor is good. I can manually start it by using a jumper wire in the slots. Blows cold when you do that.

However, it's as if the relay is not get the power that tells it to turn on. According to the page from my Haynes manual, the green white wire runs from the computer under the dash to the relay in the fuse box under the hood. There were four, but using the continuity beeper function on my multimeter, I found the right wire. A voltage check at the coming out of the computer gives me 12v, but at the fuse box, there's nothing.



Any ideas?

Thanks,
Timothy

[Ttop191]

well one cause could be a broken wire, if you are reading 12v at one end and nothing at the other. just because the continuity tester went through doesn't mean anything, there could be one single strand of wire connected and that alone would trigger the tester, yet not be able to carry the voltage. So basically just run your own wire from the pcm to the fuse box...

another option is the connector at the fuse box is corroded and therefore maintaining continuity but not making a good enough contact for the current to flow...


hope this helps

[Greencoupe2.2]

check your condensor behind the radiator for any holes.

[whiterider00]

Originally Posted by myowneq

Hello Everyone,
I can manually start it by using a jumper wire in the slots. Blows cold when you do that.

Originally Posted by Greencoupe2.2

check your condensor behind the radiator for any holes.

how would it blow cold sometimes if there was a hole in the condenser, and no refrigerant in the system?

[myowneq]

Originally Posted by Ttop191

well one cause could be a broken wire, if you are reading 12v at one end and nothing at the other. just because the continuity tester went through doesn't mean anything, there could be one single strand of wire connected and that alone would trigger the tester, yet not be able to carry the voltage. So basically just run your own wire from the pcm to the fuse box...

another option is the connector at the fuse box is corroded and therefore maintaining continuity but not making a good enough contact for the current to flow...


hope this helps

Do you think n resistance of .1 ohms make a difference in the almost broken wire theory?

[XanderWiFi]

I would say try the easiest thing first: recharge your coolant and go from there. Sounds like it is working, but just not getting as cold as it should when you compare the sun to shade. I read in the haynes manual (don't quote me on it) but at the vent, the air should be coming out around 44 degrees I think? Or 54...one of those two numbers.

[myowneq]

When I manually engage the compressor, it works. It is not a refrigerant issue.

[myowneq]

So here's an update.

I've been messing with the HVAC control panel. I have now lost all of the electrical controls to the panel. None of the four buttons work nor does the temp control. Neither do the illumination lights. And I still can't get the condensor to come on.

With everything hooked up, I can adjust the speed of the blower and the location (windshield, floor, dash). If I disconnect the double vacuum line, it goes straight to hot.

I went to Pull a Part and got a HVAC panel and I've got the exact same symptons on two different panels, one from a 2001 and another from a 2002.

I'm out of ideas unless I can understand what the wires coming out of the harness do.

There are 8 wires. brown (22 gauge), brown (18-20 gauge), white, black / white, gray, orange, blue, green. These are the bottom 8 wires on the Heater A/C Control Assembly.

Assumptions & figurations: (correct me if I'm wrong)

1) Ign brn is likely to be the 18-20 gauge wire. I should be reading 12v here.
2) Org is labeled Bat on the panel and goes to the left panel fuse block. 12v here too?
3) black / white is ground.
4) Other brn & gray are the interior lights and should be carrying 12v also with the interior lights turned up?

So what should I have on the white, green, & blue?

One other question I thought of on my trip to Pull A Part. If it is low on freon, would the computer turn this panel off?

Thanks,
Timothy

[XanderWiFi]

It could also not be the relay, but the fuse box itself in the engine compartment. Just had to recently replace mine, and at its worst it would not turn on the AC compressor and other electrical components.

[myowneq]

Here's a new one. TUrn the headlights on, the heater /ac panel comes to life.

Compressor still doesn't turn on.

And how do you access the bottom side of the underhood fuse box? I can't figure that out.

Thanks,
Timothy

[pjwallington]

My A/c is screwy also....
Under my alternator, I dont know what it is called, but the belt travels around it.. It makes a screeching sound off and on.
When you push the AC button, the part by the pulley doesnt kick in.. (Remains still)..
Im going to try and recharge my ac stuff, and Ill go from there I guess..

[myowneq]

The thing under your alternator is called the air conditioner compressor.

The screeching belt, I would suggest one of two things. One, loosen the belt and try to turn the compressor pulley by hand. If not, replace your pulley / compressor. Not sure how they come apart.

Two, if you can turn by hand, then you should check your refrigerant level. There is a plug on the frig line near the passenger front engine compartment. Pull this and put a jumper wire. If the compressor kicks on, add refrigerant. If not, you got issues elsewhere.

Timothy

[pjwallington]

Originally Posted by myowneq

The thing under your alternator is called the air conditioner compressor.

The screeching belt, I would suggest one of two things. One, loosen the belt and try to turn the compressor pulley by hand. If not, replace your pulley / compressor. Not sure how they come apart.

Two, if you can turn by hand, then you should check your refrigerant level. There is a plug on the frig line near the passenger front engine compartment. Pull this and put a jumper wire. If the compressor kicks on, add refrigerant. If not, you got issues elsewhere.

Timothy

I took the belt off, turned it by hand. and it made a sound as if there was dirt in there or something.. But I put it back together, and I will try your other suggestion.
Thanks, Pete.

[myowneq]

I'm not entirely sure of how the pulley is set up on there. I know it runs on a clutch, so I'm assuming there are bearings on the pulley. If it sounds like dirt and can jiggle a little bit, the bearings could be shot. But that's assuming there's bearings.

Tim

[robalero]

eq your better off not responding to what he post. he claims to going to be installing a twin charged 300c yet clearly just said he didn't know what the AC Compressor was

[myowneq]

Well, if he blows his car up, he blows his car up. I'm just providing what little knowledge I have on air conditioners.

And honestly, I'm out of ideas if those don't work.

[pjwallington]

Originally Posted by robalero

eq your better off not responding to what he post. he claims to going to be installing a twin charged 300c yet clearly just said he didn't know what the AC Compressor was

are we good now ? and we were getting a 6.7L stroker kit.. but dad has decided to test the new 6.L srt8 300C and shelby first..
We got off to a bad start, didnt appreciate people judging/and calling me a liar..

[a.graham52]

Originally Posted by pjwallington

We got off to a bad start, didnt appreciate people judging/and calling me a liar..

but you are

[pjwallington]

Originally Posted by a.graham52

but you are

Are you serious ? Grow up

[a.graham52]

Originally Posted by myowneq

So here's an update.

I've been messing with the HVAC control panel. I have now lost all of the electrical controls to the panel. None of the four buttons work nor does the temp control. Neither do the illumination lights. And I still can't get the condensor to come on.

With everything hooked up, I can adjust the speed of the blower and the location (windshield, floor, dash). If I disconnect the double vacuum line, it goes straight to hot.

I went to Pull a Part and got a HVAC panel and I've got the exact same symptons on two different panels, one from a 2001 and another from a 2002.

I'm out of ideas unless I can understand what the wires coming out of the harness do.

There are 8 wires. brown (22 gauge), brown (18-20 gauge), white, black / white, gray, orange, blue, green. These are the bottom 8 wires on the Heater A/C Control Assembly.

Assumptions & figurations: (correct me if I'm wrong)

1) Ign brn is likely to be the 18-20 gauge wire. I should be reading 12v here.
2) Org is labeled Bat on the panel and goes to the left panel fuse block. 12v here too?
3) black / white is ground.
4) Other brn & gray are the interior lights and should be carrying 12v also with the interior lights turned up?

So what should I have on the white, green, & blue?

One other question I thought of on my trip to Pull A Part. If it is low on freon, would the computer turn this panel off?

Thanks,
Timothy

i had an issue like this with my other alero. it once had an aftermarket remote start installed and somone put a scotchlock on the brown wire before it exited the firewall. just prior to buying the car the remote start was removed but wire repair never happend. hence i would have no heat unless i unplugged the controls. check and make sure you have all nessasary 12Vs going to your controls. also.. check fuses, make sure you didnt blow one on accident