Help with strange A/C problem, please!
Thread Starter
Instructor
Joined: Nov 2004
Posts: 157
Likes: 2
From: Santa Ana California
Help with strange A/C problem, please!
My A/C in my dual climate control is acting really wierd, it comes on in the defrost mode in the morning but when I need A/C when it gets hot I only get the recirculation fan on. Here's what I've tried so far.
Checked for codes, no codes at all.
The external temperature sensor reads about right on the HVAC display, tried disconnecting it anyway. It reads 69 degrees when disconnected but the A/C still didn't come on.
If I push the A/C button for manual A/C it turns on for a second then turns off.
Pulled both fuses for HVAC control, verified that HVAC was not functional. Waited 10 minutes and plugged in. No change. Pulled fuses for 12 hours with same result.
I also tried covering the sun sensor on the dashboard with no change. Does this need to be covered for some amount of time before it affects the HVAC system?
I haven't tried disconnecting the battery, anyone think this will have better results?
Any other ideas would be appreciated
Thanks
Bill
Checked for codes, no codes at all.
The external temperature sensor reads about right on the HVAC display, tried disconnecting it anyway. It reads 69 degrees when disconnected but the A/C still didn't come on.
If I push the A/C button for manual A/C it turns on for a second then turns off.
Pulled both fuses for HVAC control, verified that HVAC was not functional. Waited 10 minutes and plugged in. No change. Pulled fuses for 12 hours with same result.
I also tried covering the sun sensor on the dashboard with no change. Does this need to be covered for some amount of time before it affects the HVAC system?
I haven't tried disconnecting the battery, anyone think this will have better results?
Any other ideas would be appreciated
Thanks
Bill
Thread Starter
Instructor
Joined: Nov 2004
Posts: 157
Likes: 2
From: Santa Ana California
With the car running I turned off the HVAC, set the control to 70 and then pressed Auto. It immediately went to fresh air with the fan on, A/C light did not come on. Ext air temp was 56 on the display (I'm pretty sure its not that cold outside).
I also tried other temps and below 70 it would turn on the fresh air, above 70 it would turn on the recirculate. No temp would even blink the A/C light
Thanks again
I also tried other temps and below 70 it would turn on the fresh air, above 70 it would turn on the recirculate. No temp would even blink the A/C light
Thanks again
Race Director
Joined: May 2000
Posts: 14,542
Likes: 5
I wish I could help you more.
I did a search, came up with nothing.
Can you tell if the compressor is kicking in when you push Off/Auto?
Rpm drops, for example?
You've checked all the belts?
Sorry I can't help more.
I did a search, came up with nothing.
Can you tell if the compressor is kicking in when you push Off/Auto?
Rpm drops, for example?
You've checked all the belts?
Sorry I can't help more.
Thread Starter
Instructor
Joined: Nov 2004
Posts: 157
Likes: 2
From: Santa Ana California
I checked the compressor belt and its definately there and turning the pulling on the compressor. I can't tell if the compressor is trying to come on. The strange thing is that the A/C light comes on in the morning during defrost.
Thanks for the help
Thanks for the help
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From: bloomfield nj
, low refrigerant
Le Mans Master
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From: Glendale NY
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16-'17-'18- '19
Ac
With the car running I turned off the HVAC, set the control to 70 and then pressed Auto. It immediately went to fresh air with the fan on, A/C light did not come on. Ext air temp was 56 on the display (I'm pretty sure its not that cold outside).
I also tried other temps and below 70 it would turn on the fresh air, above 70 it would turn on the recirculate. No temp would even blink the A/C light
Thanks again
I also tried other temps and below 70 it would turn on the fresh air, above 70 it would turn on the recirculate. No temp would even blink the A/C light
Thanks again
Thread Starter
Instructor
Joined: Nov 2004
Posts: 157
Likes: 2
From: Santa Ana California
The tach does not move turning the system on or off during idle. It also doesn't move when I press the manual A/C button.
What's the easiest way to check the refrigerant level?
Thanks
What's the easiest way to check the refrigerant level?
Thanks
Instructor
Joined: Feb 2007
Posts: 100
Likes: 5
What year do you have? If you have a car with R-134A you can go to the Auto Parts Store (Or Walmart) and get a A/C Pressure Guage and a can of refrigerant. You want to make sure the can is attached to the guage so you don't let any frigerant out or air into your system. If you get air into your system you will hose your a/c Compressor (The mosture freezes and tears up the inside)
The Guage will tell you how much or possibly if the pressure is within "Range"
Don't over do the refrigerant. If you get too much pressure your system will also shut down.
Technically there is an ambient temperature chart to figure out how much to add, but it is just easier to meet the minimum pressure when it is 80 degrees outside, and go a little higher on the guage when it gets hotter.
If you have a 98 or older (**** I THINK ***) you have Freon (R-12) which needs to be serviced by a licensed proffesional. (Or someone with an R-12 Guage.
The Guage will tell you how much or possibly if the pressure is within "Range"
Don't over do the refrigerant. If you get too much pressure your system will also shut down.
Technically there is an ambient temperature chart to figure out how much to add, but it is just easier to meet the minimum pressure when it is 80 degrees outside, and go a little higher on the guage when it gets hotter.
If you have a 98 or older (**** I THINK ***) you have Freon (R-12) which needs to be serviced by a licensed proffesional. (Or someone with an R-12 Guage.
Instructor
Joined: Feb 2007
Posts: 100
Likes: 5
What year do you have? If you have a car with R-134A you can go to the Auto Parts Store (Or Walmart) and get a A/C Pressure Guage and a can of refrigerant. You want to make sure the can is attached to the guage so you don't let any frigerant out or air into your system. If you get air into your system you will hose your a/c Compressor (The mosture freezes and tears up the inside)
The Guage will tell you how much or possibly if the pressure is within "Range"
Don't over do the refrigerant. If you get too much pressure your system will also shut down.
Technically there is an ambient temperature chart to figure out how much to add, but it is just easier to meet the minimum pressure when it is 80 degrees outside, and go a little higher on the guage when it gets hotter.
If you have a 98 or older (**** I THINK ***) you have Freon (R-12) which needs to be serviced by a licensed proffesional. (Or someone with an R-12 Guage.
The Guage will tell you how much or possibly if the pressure is within "Range"
Don't over do the refrigerant. If you get too much pressure your system will also shut down.
Technically there is an ambient temperature chart to figure out how much to add, but it is just easier to meet the minimum pressure when it is 80 degrees outside, and go a little higher on the guage when it gets hotter.
If you have a 98 or older (**** I THINK ***) you have Freon (R-12) which needs to be serviced by a licensed proffesional. (Or someone with an R-12 Guage.
Race Director
Joined: May 2000
Posts: 14,542
Likes: 5
It comes on when you use the defroster because the unit is designed to take out any moisture inside the car so the windows don't fog up. I don't think the AC is going to come on if the outside temperature is 56degrees and you have it set at 70 degrees. I could be wrong....
