Air Conditioner not working?

When you turn the A/C on, do you hear the compressor engage under the hood? Also, have you checked Freon levels?

Take a look through this link and let me know if it helps.

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

and

https://youtu.be/4UjfQKvrB6Y ac not working video

Also, if you want to add Freon to the system, here is a link explaining how it's done:

https://www.2carpros.com/articles/air-conditioner-how-to-add-freon

Let me know if that helps. Also, let me know if you hear the compressor click on and off when the system is on.

Air Conditioning problem
1999 Honda Accord 4 cyl Two Wheel Drive 122000 miles

climate control comes on erratically, sometimes blinks, sometimes stays on and the AC works, then may randomly go off.

Sometimes tapping the control unit causes it to come on and function again. When on, the AC seems to work properly.

There are many questions about this online, but no one has explained the cause(s).

1. Loose connection?

2. Open/loose solder connection on the printed circuit board?

3. Sticky relay(s)?

4. System leaks/low pressure?

Hi rossiaa,

The control panel has an internal fault.
Usually it is a bad solder somewhere on the printed circuit board. Other possible faults are :
1. Leaking capacitors.
2. Broken flexible circuits between the 2 boards.

Thanks for that info. Is it a DIY repair? If not, any idea of the replacement cost of the unit?

AC button , recirulate botton and selector button blink with the engine running...prior to blinking the AC would shut off but then randomly turn on . The AC blows cold when it is on and the lights are not blinking but with the blinking lights it does not blow cold. I also can't change the selector to defrost, dash -floor or defrost -floor mode, nor can I turn off the recirculate botton. Thanks in advance for your help. I live in Key West Florida and it is a high humidity area.

Hi scuba2cuba,

It is quite common for the control panel to go bad and that is what I feel is the problem. You need to remove the panel to check for loose connections and most probably a rreplacement is necessary.

Since 2 weeks my car A/C is not working some times. It happens suddenly. The A/C switch doesnt show green light and I dont get cool air in side. when I start the A/C after some hours it works properly blowing cold air..I checked with a A/C recharger and it indicated that I have enough refrigerant. Can any body tell me whats going on with my car A/C. thank you..

Hi amaryadav,

When AC switch does not light up, it means the compressor is not being activated. I would suggest checking the AC switch, AC thermostat, AC relay, compressor clutch and hopefully it is not the ECM.

Thank you !!

The AC in my Mother-In-Law's Accord is not operating properly.
When the car is first started you can hear the cooling fans and the AC compressor come on. After about 4-5 seconds the cooling fans and the compressor shut off. Once they go off the inside fan comes on but only on full auto or on high fan. The compressor and outside cooling fans do not come back on. If I take the ignition and bump the ignition between run and start the compressor and cooling fans come on for 4-5 seconds and then shuts off. When the inside blower fan comes on the AC is cold. Anothe thing I noticed is that the recirculate light cycles on/off depending on which fans are running.

Hi there

Looks like the AC control unit is at fault. If you know how to repair electronic circuits, maybe you can try to salvage it, if not then get a new 1 :)

The othe rday after driving only a few miles a hissing and smoke came from under the hood. Then a blast of cold air came from the vents. The A/C was on at the time. Looking under the hood there was clear oil below the compressor relief value. All seems fine now. The A/C is not as cold as it has been, but the compressor clutch still enguages. What is the function of the relief value and what could cause it of open for a short period of time? What should I have checked?

Hi
Relief valve pops when compressor high side goes up to far to prevent damage to comp.

This guide can help us fix it

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak


Check to see if cooling fans are on and radiator coolant up to level. System not as cold because your Freon was dumped along with oil. Suggest you not run AC till repair is made costly damage may occur.
Hope this helps
Thanks for donate

When we start the car the light on the AC control panel is normal. We can turn the AC on. After running a while AC working stop and the lighting on the panel is off too. A few week ago, we found it could happen if we push the inner cycling button on. But now, AC will stop working no matter what we push any button on the control panel or not.
If the inner cabin temperature is too high, AC can not be turned on when we start engine.

thanks.

the control panel will have to be checked for failed switches. this is best done by a shop if you do not have the expierence required for this repair.

Roy

I press the air control ( on the dash)--the light does not go on no cold air--the same with the heat--no light on no heat-- the fan blows but no air comes out of the dash vents or front window vents-- the air (not hot or cold comes out the floor vents---

Have you checked the fuses yet? There are 2 fuse panels inside thecar, one passenger side (check fuse 13- 7.5 amp) then one drivers side (check fuses 3-7.5 amp & 6 -15 amp). Then in the underhood fuse panel check fuses 56-40 amp,57,58 are both 20 amp

Air Conditioning problem
1999 Honda Accord 4 cyl Two Wheel Drive Automatic 89.000 miles
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how much freon do you put in the car air conditioner not blowing out cold air

If low R-134a is your problem then you can buy a canister with a gage on it and it will tell you when the system has proper pressure. One canister should take care of the problem if you don't have a leak.

when you turn on the a/c the a/c light blinks on and off. the fan blows but no cold air. could this be a wiring problem?

It could be a wiring or sensor fault. Retrieve the trouble code to find out more about the problem.

how do i get the trouble code? i know on some cars you can turn the switch off and on and the check engine light will blink out the code. is the case with this car?

Is yours manual or automatic climate control?

it is a manual control

How To Use The Self­Diagnostic Function

The HVAC control unit has a self­diagnostic function for the heating, ventilation, and air
conditioning system. To run the self­diagnostic function, do the following:
1. Turn the ignition switch to LOCK (0), and then to ON (II).
2. Set the FAN CONTROL dial to OFF, the TEMPERATURE CONTROL dial on Max
Cool, and select the VENT mode.
3. Turn the ignition switch to LOCK (0), and then to ON (II).
4. Press and hold the RECIRCULATION CONTROL button, then within 10 seconds press
and release the REAR WINDOW DEFOGGER/MIRROR DEFOGGER button five times.
Release the RECIRCULATION CONTROL button? the recirculation indicator blinks two
times, then the self­diagnosis begins.

1 An open in the air mix control motor circuit
2 A short in the air mix control motor circuit
3 A problem in the air mix control linkage, door, or motor circuit
4 An open in the mode control motor circuit
5 A short in the mode control motor circuit
6 A problem in the mode control linkage, doors, or motor circuit
7 An open in the recirculation control motor circuit
8 A short in the recirculation control motor circuit
9 A problem in the recirculation control linkage, door, or motor circuit
10 An open or short in the mode control circuit
11 A problem in the mode control linkage, doors, or motor circuit
12 A problem in the blower motor circuit
13 HVAC control unit internal error
14 An open in the evaporator temperature sensor circuit
15 A short in the evaporator temperature sensor circuit

The vent will always blow air, whether it blows it hot or cold depending on where I've set the thermostat is completely up to the car. I've tried banging underneath the glove compartment to no avail. Usually when it does come on. It's been blinking on and off for a while, then it will come on. If I immediately try to push a button to regulate which vents I want to air to come out. It will immediately go off, but resume it's blinking on and off in a few minutes. So it is always blowing air no problem, but it is not cool air until the lights come on. The same problem is with the heater. Any ideas?

Hi timbogeorge,

Symptom indiates a fault with the air mix door.

Is system automatic HVAC or manual HVAC?

It is manual HVAC. What is the air mix door and how can I fix it?

Syatem is equipped with self diagnostic . Let me know thw results. ENTERING SELF-DIAGNOSTICS 1. Turn ignition on. Turn blower switch OFF. Place recirculation control knob in recirculated air position (indicator light will come on). Press and hold recirculation control switch to fresh air position (indicator light goes off). 2. Continue to hold recirculation control switch until indicator light comes on for 2 seconds. At this point it will blink the Diagnostic Trouble Codes (DTCs) to indicate the faulty component. One blink indicates air mix control motor, 2 blinks indicates mode control motor, and 3 blinks indicates evaporator temperature sensor. See Fig. 6 . If indicator lights come on, test appropriate component. NOTE: Fault information is not retained in memory. In case of multiple problems, the light will indicate the DTC with the least number of blinks.

Air mix door is for changng the air flow between A/C and heater.

the AC was blowing warm air. I tried to re charge the system and noticed the compressor and fans turned on and off.

That can mean too much refrigerant. You cannot simply randomly add refrigerant. It requires a very specific weight of refrigerant. The only way to get the right amount is to have it entirely evacuated and recharged with the correct amount. You are going to damage the system if your do not.

Thanks for the post, KHLOW2008. The self diagnostic steps you included worked for my 2001 3.0L and I got 1 blink (air mix control motor).