AC not turning on?
97GreenGTP
05-30-2006, 09:22 PM
I have a 97 GTP. Last year the AC was not blowing very cold air, so I put two cans of the refigerant in the system. Cooling was improved.
Weather being hot in the last couple of days in the mid-west, I turned the AC on and it will not blow cold air at all. Popped the hood and found out that the compressor was not coming on.(The AC light at the switch on instrument panel comes on) The fans are supposed to come on as soon as you turn on the AC even if the car is cold and they are not turning on either.
I am planning to take the car to the mechanic for a AC diagnosis.
Can anybody tell me about the possible reasons for the AC not turning on?
Thanks
Weather being hot in the last couple of days in the mid-west, I turned the AC on and it will not blow cold air at all. Popped the hood and found out that the compressor was not coming on.(The AC light at the switch on instrument panel comes on) The fans are supposed to come on as soon as you turn on the AC even if the car is cold and they are not turning on either.
I am planning to take the car to the mechanic for a AC diagnosis.
Can anybody tell me about the possible reasons for the AC not turning on?
Thanks
BNaylor
05-31-2006, 06:50 AM
Sounds like you have a leak in the system. If low refrigerant pressure is detected the compressor will not turn on until the charge is brought back up.
The mechanic can run A/C diagnostics to determine the specific cause and run a leak detector.
The mechanic can run A/C diagnostics to determine the specific cause and run a leak detector.
richtazz
05-31-2006, 11:38 AM
:iagree:
97GreenGTP
06-01-2006, 10:56 PM
Ok, Today I got freon and dye in the system(Paid $ 100) and was told by the mechanic that i need to run it for few days before he can check the leak.
Also he said that the system maintained the vacuum but the low side and high side pressure were 70 and 140 respectively. After I got the car back, I realised that the air was not cold enough and it will come from the floor vents although I selected the dash vents.
Can someone help me in diagnosing the reason for lower pressure(not cold enough air) and also air coming from the floor vent although i selected dash vent.
Thanks
Also he said that the system maintained the vacuum but the low side and high side pressure were 70 and 140 respectively. After I got the car back, I realised that the air was not cold enough and it will come from the floor vents although I selected the dash vents.
Can someone help me in diagnosing the reason for lower pressure(not cold enough air) and also air coming from the floor vent although i selected dash vent.
Thanks
BNaylor
06-02-2006, 01:03 AM
Sounds like your mechanic doesn't know what he is doing. :shakehead
The 70 low and 140 high should have been a big red flag.
Normally, when you get low side pressure too high and high side pressure too low such as the readings obtained that means the compressor is in a de-stroked or in a no-pump condition.
Therefore, there is a high probability you have a bad compressor (internally) which may also be the cause of the leak.
For the improper vent operation you may have a bad vacuum line connection from the supercharger to the HVAC system or a bad HVAC climate control head unit.
The 70 low and 140 high should have been a big red flag.
Normally, when you get low side pressure too high and high side pressure too low such as the readings obtained that means the compressor is in a de-stroked or in a no-pump condition.
Therefore, there is a high probability you have a bad compressor (internally) which may also be the cause of the leak.
For the improper vent operation you may have a bad vacuum line connection from the supercharger to the HVAC system or a bad HVAC climate control head unit.
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