A/C light flashing
Thread Starter
Navigator
Joined: Sep 2007
Posts: 9
Likes: 0
From: Del Rio TX
A/C light flashing
Hello, I have a '99 Contertible. I've been battling the HVAC system for a while now and have made some progress...but not done yet. My original problem was heat on one side and cold on the other regardless of the switch settings. Shortly after my fan started acting up and wouldn't turn on. I was getting codes for a bad temperature actuator. I replaced the right side temp actuator and it solved those problems, but also gave me a new one. When I turn on the A/C, the light just flashes and doesn't engage the compressor. I tried pulling the battery and resetting fuses, but still no A/C. Any suggestions?
Thread Starter
Navigator
Joined: Sep 2007
Posts: 9
Likes: 0
From: Del Rio TX
I thought of that as a possibility, but the coolant level was fine right before the actuator change. I'll double check the level. Would I get a code for low coolant? I don't have any HVAC codes currently.
Safety Car
Joined: Aug 2000
Posts: 4,933
Likes: 30
From: San Rafael CA
What is the outside air temperature as displayed on the HVAC screen ??? If it is below about 40 degrees, the A/C compressor can not be turned on, and the light blinks to indicate this. See page 3-9 in your Owner's Manual.
Tech Contributor
Joined: Oct 1999
Posts: 41,058
Likes: 9,820
From: Charlotte, NC (formerly Endicott, NY)
Thread Starter
Navigator
Joined: Sep 2007
Posts: 9
Likes: 0
From: Del Rio TX
Thanks for the suggestions. I wish that were the problem. The outside temp has been over 70 and still no A/C. I'll try to get it serviced with coolant. Hopefully that's it. I have a brand new control head and everything else seems fine. I don't know what else it would be.
Safety Car
Joined: Aug 2000
Posts: 4,933
Likes: 30
From: San Rafael CA
ViperDriver,
It doesn't matter what the actual air temp is ... the question is ... what is the DISPLAYED temperature ???? If the Outside Air Temp (OAT) sensor is failing and it is displaying something like 29 degrees ... then the A/C won't come on. If the displayed temp is low, take the car out for a 5 to 10 minute run and see if the temp updates to the correct temperature. If not the OAT should be replaces (the part is about $10.00 and it is a five minute job).
Otherwise, you say you have no HVAC codes, are there others ??? Some engine codes can cause the PCM to determine that the strain of the A/C compressor is too much, and since the PCM controls the compressor clutch, it won't engage it.
It doesn't matter what the actual air temp is ... the question is ... what is the DISPLAYED temperature ???? If the Outside Air Temp (OAT) sensor is failing and it is displaying something like 29 degrees ... then the A/C won't come on. If the displayed temp is low, take the car out for a 5 to 10 minute run and see if the temp updates to the correct temperature. If not the OAT should be replaces (the part is about $10.00 and it is a five minute job).
Otherwise, you say you have no HVAC codes, are there others ??? Some engine codes can cause the PCM to determine that the strain of the A/C compressor is too much, and since the PCM controls the compressor clutch, it won't engage it.
Intermediate
Joined: Jun 2017
Posts: 41
Likes: 2
I was wondering why it was flashing. You are right, just as the manual states. I thought there was something wrong, but I am happy there isn't. Thank you very much!!
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