It's my fault......

[Cadillakin'98]

I swear it really sucks when you help someone out with their vehicle and then everything that goes wrong with their car from that point on, even 6 months later, is related to the time you fixed something totally unrelated before. So, I need help from those who know their A/C's.
I fixed an overheating issue on this girls car (2000 Grand Prix) about 6 months ago, and no her A/C quit working as a result of (in her mid anyway). Did her A/C work after I worked on it? Yes. Has she been using the A/C recently? Yes. Is it still my fault? She thinks so. The only reason I'm still willing to help troubleshoot her problem is because she is a good friend. So here's the problem:

Blows air, but not cold, no change in temp from vent to A/C, it has freon (real close to full), compressor does come on, head unit was changed. head unit recently replaced (new); thus the cwitches/controls work properly, linkage (cables) are all conected and adjusted (someone else's work- not mine but I'm taking their word for it.

For the record, I work a body shop and am very mechanically inclined. So I have eliminated the obvious stuff already. Also, I understand A/C units/comonts/work is a different class itself. Thus I can only diagnose the basics listed above.

Anyone out there have any GOOD suggestions or theoriies? Your input would be very appreciated. (vehicle = '00 GrandPrix)

[kustomkid54]

Originally Posted by Cadillakin'98

I swear it really sucks when you help someone out with their vehicle and then everything that goes wrong with their car from that point on, even 6 months later, is related to the time you fixed something totally unrelated before. So, I need help from those who know their A/C's.
I fixed an overheating issue on this girls car (2000 Grand Prix) about 6 months ago, and no her A/C quit working as a result of (in her mid anyway). Did her A/C work after I worked on it? Yes. Has she been using the A/C recently? Yes. Is it still my fault? She thinks so. The only reason I'm still willing to help troubleshoot her problem is because she is a good friend. So here's the problem:

Blows air, but not cold, no change in temp from vent to A/C, it has freon (real close to full), compressor does come on, head unit was changed. head unit recently replaced (new); thus the cwitches/controls work properly, linkage (cables) are all conected and adjusted (someone else's work- not mine but I'm taking their word for it.

For the record, I work a body shop and am very mechanically inclined. So I have eliminated the obvious stuff already. Also, I understand A/C units/comonts/work is a different class itself. Thus I can only diagnose the basics listed above.

Anyone out there have any GOOD suggestions or theoriies? Your input would be very appreciated. (vehicle = '00 GrandPrix)




















DT

Well that's what you get for being a nice guy. You should know if you fixed it, no matter how long ago, you have to fix everything else that goes wrong with it.
Tell her to blow it out her ---. She's nuts. That's like saying if you washed her car, you have to repaint it 10 years later.

Good luck

[Ripn12s]

Dont have an answer for ya, but if you find out whats wrong let me know. My car is doing the same thing.

Does she have Digital Daul climate controls or the analog knobs??

[kustomkid54]

You know, I just went thru all 4 manuals (GM service manuals). They have 25 pages on how to adjust seat belts. 16 pages of elec. hook ups to check power on the 3.1 GP's. But not a thing on troble shooting A/C. Time for some more books.
Sorry.

[Cadillakin'98]

A/C units are a whole different ball game. Did your books say something like ".....take it to a Motor Vehicle Air Conditioning (MVAC) trained and EPA certified trained technician......"

It's as if our repair manuals have to be regulated by the federal government now. Since A/C's use freon, the damn EPA won't give any information in a repair manual now. What a bunch of haters. That's why I asked around on here.

And kustomkid, you are absolutely right, I shouldn't have been nice and helped her in the first place. Then her car would only have 5000 miles on it, no dents/scratches, still have that new car smell, Service Engine Soon Light wouldn't exist, correct air pressure in tires, and of course the A/C would be like a freezer. But I screwed that all up once I fixed the overheating issue caused by someone (like a female driver) who mixed pink and green antifreeze. I mean, I even screwed up equal tire pressure, and even the radio staions she like don't come in now.

Let this be a lesson kid (Mr. Kustom)

[Cadillakin'98]

Life is a bitch, and then you marry one.

[Ripn12s]

When A/C mode is selected, the ac control head or the ac programmer supplies a 12volt signal to the pcm ac request input. The ac compressor clutch relay is controlled by the pcm. The pcm provides a ground path for ac relay coil. When the ac compressor relay is engaged battery boltage is supplied to the comrpessor clutch coil. The pcm will enable the ac comrpessor clutch whever the engine is running and the ac has been requested unless one or more of the following conditions are presetn

[Ripn12s]

throttle angle si greater then 96 %
ac head pressure is greater then 440 psi (4.6 volts) or less then 32 psi (.o3 volts) as determind by the ac refrigerant pressure sensor.
ingnition 1 voltage is below 10 volts
Engine speed is greater then 4392 rpm for less then a second
Engine speed is greater then 4400 rpm for any amount of time
ECT si great then 255 deg f
IAT is less then 41 deg f

[Ripn12s]

> ambient air temp above 41 deg f
> ac pressure above .3 volts (32 C)
> coolant temp below 250 deg f

1. ac selector off
2. ignition on, engine off
3. listen for engagement of ac clutch
Is the ac clutch engage?
Yes goto step 24
No go to step 4

[kustomkid54]

Originally Posted by Cadillakin'98

A/C units are a whole different ball game. Did your books say something like ".....take it to a Motor Vehicle Air Conditioning (MVAC) trained and EPA certified trained technician......"

It's as if our repair manuals have to be regulated by the federal government now. Since A/C's use freon, the damn EPA won't give any information in a repair manual now. What a bunch of haters. That's why I asked around on here.

And kustomkid, you are absolutely right, I shouldn't have been nice and helped her in the first place. Then her car would only have 5000 miles on it, no dents/scratches, still have that new car smell, Service Engine Soon Light wouldn't exist, correct air pressure in tires, and of course the A/C would be like a freezer. But I screwed that all up once I fixed the overheating issue caused by someone (like a female driver) who mixed pink and green antifreeze. I mean, I even screwed up equal tire pressure, and even the radio staions she like don't come in now.

Let this be a lesson kid (Mr. Kustom)

These are the "GM Authentic Technical Service Information Manuals" 4 book set. Same ones the dealers use.
You know I just went thru the 1997 GP service manual that I have, has 9 chapters on A/C. All on PDF files. How much did they change in three years?

[Ripn12s]

step 4:

1.start engine
2. select ac mode
3. observe ac compressor

is the ac compressor clutch engaged
If yes then refer to diagnostic aids
if No go to step 5 >>> requires scan tool
..................................

step 24 requires a scan tool to monitor A/C request

[kustomkid54]

Tim,
I think you have the same manuals that I have. These?

http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT

[Ripn12s]

if u have them in pdf then why the hell am i coping this from the manual?

[Cadillakin'98]

Thanks for the knowledge ripin. You must know what its like to be a nice guy, huh?! Bad thing is this girl is strictly just a friend to me. So I essential don't get any satisfaction by helping her out. However, I did get gratification fixing her car and knowing she wouldn't brake down due to an overheating issue when she had to make a 750 mile trip out of state. If you don't mind ripin, could you please define ECT and IAT. Actually just what theey stand for would be sufice. And thanx again for the knowledge.

[kustomkid54]

Originally Posted by Ripn12s

if u have them in pdf then why the hell am i coping this from the manual?

I have the ones for the 1997, on disc.