ac/heater problem
Thread Starter
Instructor
Joined: Nov 2004
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From: Manahawkin New Jersey
ac/heater problem
Help! My heater/ac is not functioning. I have the fan settings all the way up, and am getting no air out of it. I did a diagnostics and no error codes were listed. I took it to the dealer and they say i need a new dual zone dash control. Any ideas? Its getting cold a I want to drive my vette as long as possible.
Last edited by Sixants; Dec 2, 2004 at 05:55 PM.
Thread Starter
Instructor
Joined: Nov 2004
Posts: 208
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From: Manahawkin New Jersey
I've had the oil changed, harmonic balancer replaced, belts replaced. Just bought it several months ago, and when I first got it. the fan would come on every once and a while with a loud nasty sound but would then turn off again. Now it doesn't come on at all.Thanks!
Safety Car
Joined: Dec 2002
Posts: 4,010
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From: SE Idaho
St. Jude Contributor
Could also be just a blower motor, which is a heck of a lot less expensive to replace, or should be.
Play with your head (A/C/Heater Head
) and see if the following happens.
1. Set to maximum hot and see if you can feel some heat coming out of the vent. Even with no blower motor, a small amount of heat will exit the vents.
2. Set to maximum cold and see if it turn to cold air.
3. Turn on the A/C and see if the compressor clutch kicks in.
If all three modes work ok, I would check to see if there is power to the blower motor. If no power, could be the head. If power is there, but the blower does not work, I would believe it was the blower motor.
Since I have no idea what year car we are talking about, or if you have auto or manual A/C, I really can't help any further.
However, if you have a manual system, it does not sound like the blower motor resistor is bad. Usual symptoms of a bad resistor is the blower motor will only work in high, but in no other settings. (The resistor is used to drop the voltage down, but when on High, the resistor is bypassed.)
If you have auto A/C, there is a blower motor control processor that takes the place of the blower motor resistor. This component controls the blower motor according to your manually set speeds on the HVAC control head.
So, if you have an auto A/C system, check power to the plug that goes to the control processor, and if power is available, then it could be the processor or the blower motor.
These are the simple diagnostic steps. Needless to say, if you have manual A/C, it gets easier
Added information:
Since you say it made sounds when first starting up, then stopped completely, I would go after the blower motor.
Easy to remove,
Remove the the passenger side sound panel, under the glove box.
Disconnect the blower motor electrical connector.
Disconnect the blower motor cooling tube from the HVAC module.
Remove the blower motor retaining screws.
Remove the blower motor from the HVAC module.
And like Lonestar stated, check the fuse. Sometimes I get to wrapped up with trying to explain electrical diagnosis and forget one of the obvious and easiest things to check first.
Good luck....
Play with your head (A/C/Heater Head
) and see if the following happens.1. Set to maximum hot and see if you can feel some heat coming out of the vent. Even with no blower motor, a small amount of heat will exit the vents.
2. Set to maximum cold and see if it turn to cold air.
3. Turn on the A/C and see if the compressor clutch kicks in.
If all three modes work ok, I would check to see if there is power to the blower motor. If no power, could be the head. If power is there, but the blower does not work, I would believe it was the blower motor.
Since I have no idea what year car we are talking about, or if you have auto or manual A/C, I really can't help any further.
However, if you have a manual system, it does not sound like the blower motor resistor is bad. Usual symptoms of a bad resistor is the blower motor will only work in high, but in no other settings. (The resistor is used to drop the voltage down, but when on High, the resistor is bypassed.)
If you have auto A/C, there is a blower motor control processor that takes the place of the blower motor resistor. This component controls the blower motor according to your manually set speeds on the HVAC control head.
So, if you have an auto A/C system, check power to the plug that goes to the control processor, and if power is available, then it could be the processor or the blower motor.
These are the simple diagnostic steps. Needless to say, if you have manual A/C, it gets easier
Added information:
Since you say it made sounds when first starting up, then stopped completely, I would go after the blower motor.
Easy to remove,
Remove the the passenger side sound panel, under the glove box.
Disconnect the blower motor electrical connector.
Disconnect the blower motor cooling tube from the HVAC module.
Remove the blower motor retaining screws.
Remove the blower motor from the HVAC module.
And like Lonestar stated, check the fuse. Sometimes I get to wrapped up with trying to explain electrical diagnosis and forget one of the obvious and easiest things to check first.
Good luck....
Last edited by WhiteC5Vette; Dec 2, 2004 at 07:44 PM.
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Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by WhiteC5Vette
Could also be just a blower motor, which is a heck of a lot less expensive to replace, or should be.
Play with your head (A/C/Heater Head ) and see if the following happens.
1. Set to maximum hot and see if you can feel some heat coming out of the vent. Even with no blower motor, a small amount of heat will exit the vents.
2. Set to maximum cold and see if it turn to cold air.
3. Turn on the A/C and see if the compressor clutch kicks in.
If all three modes work ok, I would check to see if there is power to the blower motor. If no power, could be the head. If power is there, but the blower does not work, I would believe it was the blower motor.
Play with your head (A/C/Heater Head
) and see if the following happens.1. Set to maximum hot and see if you can feel some heat coming out of the vent. Even with no blower motor, a small amount of heat will exit the vents.
2. Set to maximum cold and see if it turn to cold air.
3. Turn on the A/C and see if the compressor clutch kicks in.
If all three modes work ok, I would check to see if there is power to the blower motor. If no power, could be the head. If power is there, but the blower does not work, I would believe it was the blower motor.
It could very well be a dead blower motor. They are not very hard to change out either. Be sure to check all applicable fuses and relays too. HTH
Thread Starter
Instructor
Joined: Nov 2004
Posts: 208
Likes: 0
From: Manahawkin New Jersey
Sorry about that. 1998, Auto dual zone control. I definately can feel a small amout of heat(takes 45min to get windows defrosted). But when I try to turn on a/c, I get blinking lights and no a/c. I have checked fuses and will doulble check again.Thanks!!!!
Safety Car
Joined: Dec 2002
Posts: 4,010
Likes: 1
From: SE Idaho
St. Jude Contributor
Originally Posted by Sixants
Sorry about that. 1998, Auto dual zone control. I definately can feel a small amout of heat(takes 45min to get windows defrosted). But when I try to turn on a/c, I get blinking lights and no a/c. I have checked fuses and will doulble check again.Thanks!!!!
If you turn down the thermostat to 60 degrees, does the heat cool down?
Not sure what is happening with the A/C light. If you want, send me an email with your email address, and I can send a file with the actual troubleshooting steps for the blower motor. If you are good with a DVOM, you might be able to confirm if it is the blower motor or not.
