A/C control problem
Thread Starter
Racer
Joined: Dec 2006
Posts: 372
Likes: 2
From: Ft. Lauderdale FL
A/C control problem
OK...I did try a search but came up short. I'm not mechanically inclined so I could have possibly searched under the wrong heading or came up with my answer but completely missed it.
At any rate, my A/C has been cutting in and out lately. Not the blower mind you but rather the cold "A/C" air. It seems to happpen first thing when I get in the car (2003 Z06) or after a short burst of hard driving or acceleration.
What happens is the A/C button goes from being lit to being unlit and the fan no longer blows cold air. When it cuts off, I have to repeatedly hit the A/C button for the light to come back on and the fan begins to blow cold air again.
I would say it happens more often right after the engine temp goes up, again after periods of hard acceleration or "faster" driving. I don't dog the car, she is my baby! But, I do get on it once in a while but hey, it's a vette.
Any advice on where to start towards a solution is most appreciated
.
At any rate, my A/C has been cutting in and out lately. Not the blower mind you but rather the cold "A/C" air. It seems to happpen first thing when I get in the car (2003 Z06) or after a short burst of hard driving or acceleration.
What happens is the A/C button goes from being lit to being unlit and the fan no longer blows cold air. When it cuts off, I have to repeatedly hit the A/C button for the light to come back on and the fan begins to blow cold air again.
I would say it happens more often right after the engine temp goes up, again after periods of hard acceleration or "faster" driving. I don't dog the car, she is my baby! But, I do get on it once in a while but hey, it's a vette.
Any advice on where to start towards a solution is most appreciated
.
Pro
Joined: Sep 2007
Posts: 735
Likes: 7
From: Bucks County Pa
AC Cutting Out
Hi, it sounds like your unit is cutting out when you get on it. This is normal, SEE BELOW
+++++++++++++++++++++++++++++++++++
The A/C system can be engaged by pressing the A/C switch. The A/C switch will illuminate when the A/C switch is pressed to the on position. Pressing the A/C switch the control module grounds A/C request signal circuit from the powertrain control module (PCM). The following conditions must be obtained before A/C compressor engagement is allowed:
The engine coolant temperature (ECT) is less than 121°C (250°F)
The engine RPM is more than 550 RPM
The A/C pressure is between 207 kPa (30 psi) and 2826 kPa (410 psi)
The A/C request signal circuit is grounded.
Once engaged, the compressor clutch will be disengaged for the following conditions:
The throttle position is 100 percent
The A/C pressure is more than 2826 kPa (410 psi)
The A/C pressure is less than 207 kPa (30 psi)
The engine coolant temperature (ECT) is more than 121°C (250°F)
The engine speed is more than 5,500 RPM
The transmission shift
The PCM detects excessive torque load
The PCM detects insufficient idle quality
The PCM detects a hard launch condition
When the compressor clutch disengages, the compressor clutch diode protects the electrical system from a voltage spike.[/COLOR]+++++++++++++++++++++++++++++++++++
If your AC is cutting out when the above in red is not the cause, it would be a good idea to check the charge level. The Link below is Plasticfans excellant tutorial on recharging the unit. Also it is a good idea to make very sure that your condenser, and radiator are clear and not blocked with debris, on the outside surfaces, and in between the two
Good Luck
http://forums.corvetteforum.com/show...ghlight=ac+101
+++++++++++++++++++++++++++++++++++
The A/C system can be engaged by pressing the A/C switch. The A/C switch will illuminate when the A/C switch is pressed to the on position. Pressing the A/C switch the control module grounds A/C request signal circuit from the powertrain control module (PCM). The following conditions must be obtained before A/C compressor engagement is allowed:
The engine coolant temperature (ECT) is less than 121°C (250°F)
The engine RPM is more than 550 RPM
The A/C pressure is between 207 kPa (30 psi) and 2826 kPa (410 psi)
The A/C request signal circuit is grounded.
Once engaged, the compressor clutch will be disengaged for the following conditions:
The throttle position is 100 percent
The A/C pressure is more than 2826 kPa (410 psi)
The A/C pressure is less than 207 kPa (30 psi)
The engine coolant temperature (ECT) is more than 121°C (250°F)
The engine speed is more than 5,500 RPM
The transmission shift
The PCM detects excessive torque load
The PCM detects insufficient idle quality
The PCM detects a hard launch condition
When the compressor clutch disengages, the compressor clutch diode protects the electrical system from a voltage spike.[/COLOR]+++++++++++++++++++++++++++++++++++
If your AC is cutting out when the above in red is not the cause, it would be a good idea to check the charge level. The Link below is Plasticfans excellant tutorial on recharging the unit. Also it is a good idea to make very sure that your condenser, and radiator are clear and not blocked with debris, on the outside surfaces, and in between the two
Good Luck
http://forums.corvetteforum.com/show...ghlight=ac+101
Last edited by bestvettever; Nov 3, 2008 at 11:50 PM.
