Weird AC problem
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
Weird AC problem
Well I took my vette out for a ride yesterday, top down, and then stopped by the grocery store. Put the top back up, and on the way home, I set the AC to 60 degrees, and it would cool for a little bit, and then shift to heat for about 5 to 10 seconds. This happened several times. Any Ideas on what would cause this?
Le Mans Master
Joined: Mar 2002
Posts: 5,300
Likes: 4
From: Mississauga, Ontario Corvettes were built to be driven...not trailered
St Jude Donor '07-'08-'09
Re: Weird AC problem (Red 86 4+3)
My first question is do have the manual AC controls or the Climate Control version...if its the latter one, your system was probably just trying to figure out what the inside temp was in your car...
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
Re: Weird AC problem (Quik86)
Quik 86,
It is the climate control. I turned it down to 60, (lowest setting) and I thought that was supposed to lock it in the on position. Its never done this before, and it was in the 90's inside the car and about 84 outside the car. It didnt seem like it was trying to adjust the temp. It would go from cooling to hot air from the heater. I could hear the air speed change when it was opening the door to the heater. I suspect there is a sensor somewhere, or the control panel is dying. I just didnt know where to start checking.
It is the climate control. I turned it down to 60, (lowest setting) and I thought that was supposed to lock it in the on position. Its never done this before, and it was in the 90's inside the car and about 84 outside the car. It didnt seem like it was trying to adjust the temp. It would go from cooling to hot air from the heater. I could hear the air speed change when it was opening the door to the heater. I suspect there is a sensor somewhere, or the control panel is dying. I just didnt know where to start checking.
Racer
Joined: Apr 2002
Posts: 389
Likes: 0
From: Micco FL
Re: Weird AC problem (Red 86 4+3)
Am experiencing the exact same problem on my 92 LT1. Air works wonderful for 30 seconds then hot as blazes for 5 seconds and keeps this up. This occured first about two weeks ago. Took it to a non-vette mechanic who told me there is nothing wrong with the AC it is probable a module inside...so I drove it over the weekend and fired the compressor.
Been doing a lot of trouble shooting with the hepl of people on this forum and believe that I have it down to one of three things: 1) The head (where you press the buttons); 2) the CCM; or 3) the A/C Programmer. I have the GM manuals but am having a bear of a time finding the test procedures for A/C Programmer. A scan of the CCM showed no faults. I am also trying to find out what the numbers mean on the control panel when you push both the up and down fan arrows at the same time.
Still haven't figured this one out and will probable just replace the Programmer in the next few days if I can't find anything else out. Will keep you posted...and you please do likewise.
Been doing a lot of trouble shooting with the hepl of people on this forum and believe that I have it down to one of three things: 1) The head (where you press the buttons); 2) the CCM; or 3) the A/C Programmer. I have the GM manuals but am having a bear of a time finding the test procedures for A/C Programmer. A scan of the CCM showed no faults. I am also trying to find out what the numbers mean on the control panel when you push both the up and down fan arrows at the same time.
Still haven't figured this one out and will probable just replace the Programmer in the next few days if I can't find anything else out. Will keep you posted...and you please do likewise.
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
Re: Weird AC problem (PTz-92-LT1)
I am also trying to find out what the numbers mean on the control panel when you push both the up and down fan arrows at the same time.
Still haven't figured this one out and will probable just replace the Programmer in the next few days if I can't find anything else out. Will keep you posted...and you please do likewise.
Still haven't figured this one out and will probable just replace the Programmer in the next few days if I can't find anything else out. Will keep you posted...and you please do likewise.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Re: Weird AC problem (PTz-92-LT1)
I am also trying to find out what the numbers mean on the control panel when you push both the up and down fan arrows at the same time.
Still haven't figured this one out and will probable just replace the Programmer in the next few days if I can't find anything else out. Will keep you posted...and you please do likewise.
Still haven't figured this one out and will probable just replace the Programmer in the next few days if I can't find anything else out. Will keep you posted...and you please do likewise.
Racer
Joined: Apr 2002
Posts: 389
Likes: 0
From: Micco FL
Re: Weird AC problem (Red 86 4+3)
Thank you for the C4 Diagnostic Code link.
I have a Kilbrew Code Analyzer and it shows NO codes on all zones (other than a right front tire pressure sensor).
When the up and down arrows of the head are pressed here are the A/C codes:
1: 76
2: 130
3: 77
4: 196
5: 105
6: 30 (engine at idle)
7: 00 (in park)
9: 10
10: 128
11: 128
12: 120
16: 140
17: 128
30: 60 (Rage is suppose to be 0 to 50)
31: 150
34: 114
35: -155
36: 00
37: 00
Not sure what all this means, but the only thing out of range is #30 being 60.
Comments, ideas?
I have a Kilbrew Code Analyzer and it shows NO codes on all zones (other than a right front tire pressure sensor).
When the up and down arrows of the head are pressed here are the A/C codes:
1: 76
2: 130
3: 77
4: 196
5: 105
6: 30 (engine at idle)
7: 00 (in park)
9: 10
10: 128
11: 128
12: 120
16: 140
17: 128
30: 60 (Rage is suppose to be 0 to 50)
31: 150
34: 114
35: -155
36: 00
37: 00
Not sure what all this means, but the only thing out of range is #30 being 60.
Comments, ideas?
