Air Conditioner & Defroster Question

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I have a 2003 Ford Ranger 3.0L V6. I noticed today that when I tried to defrost my windshield this morning that nothing happened. Usually I've got a clear windshield in a few minutes. Didn't think anything about it til I turned the truck off and heard a little squeal. So then I tried to turn on my AC and the air coming out of the AC was much warmer than the vent air. It was 35 this morning.I could tell that the AC was not working. Could I have a bad compressor bearing causing the AC & Defroster not to work or is my compressor shoot. I do not hear any of the usual cycling of the compressor like when the freon gets low. This is the first AC/Defroster problem I've ever had. Can I get some input?
 
When it's near freezing the AC doesn't work because it itself will freeze up.
 
Originally Posted By: dgee
no need for your AC compressor during the cold months.


True, but it is needed, or helpful I should say to run the a/c at least once a week for several minutes/cycle to keep everything in working order.. much easier than not being used all winter then something froze up (not the condenser lol) like the compressor etc..
 
Actually defroster needs the ac- in my car the ac kicks in when you use defrost- it dries the air. I have had other cars where the manual stated the same and was told to use ac with defrost for best results. Most cars today turn the ac on when you use the defroster.
 
Originally Posted By: oilcoholic
I have a 2003 Ford Ranger 3.0L V6. I noticed today that when I tried to defrost my windshield this morning that nothing happened. Usually I've got a clear windshield in a few minutes.


1. Does the blower still work?

2. Are you still getting air coming out the top of the dashboard like you're supposed to?
 
Originally Posted By: tdpark
Actually defroster needs the ac- in my car the ac kicks in when you use defrost- it dries the air. I have had other cars where the manual stated the same and was told to use ac with defrost for best results. Most cars today turn the ac on when you use the defroster.


+1 An added benefit of newer cars running the A/C when in the defrost mode (both of our cars do) is that the A/C system is "exercised" over the winter months, circulating oil in the system and reducing the chance of refrigerant leakage.
 
Originally Posted By: tdpark
Actually defroster needs the ac- in my car the ac kicks in when you use defrost- it dries the air. I have had other cars where the manual stated the same and was told to use ac with defrost for best results. Most cars today turn the ac on when you use the defroster.


My truck turns the AC on anytime the defroster is on. Hence the reason why I turned the AC on to see if it was working. And thanks to the one who said I didn't need AC in winter, well to a point you are wrong. I need the AC to work for my defroster to work properly. Blower is working and air is coming out of all vents.
 
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Originally Posted By: oilcoholic
Blower is working and air is coming out of all vents.


Are you getting warm air coming out of the defroster vent, or cold outside air?
 
Originally Posted By: Merkava_4
Originally Posted By: oilcoholic
Blower is working and air is coming out of all vents.


Are you getting warm air coming out of the defroster vent, or cold outside air?


Warm air is coming out all vents but the AC is not kicking in to clear the windshield as before. Also, I switched the thermostat over to cold and I didn't get AC air just ambiant temperature air. As I said earlier, the AC defaults to on when you turn the defroster on.
 
The compressor may cycle on/off under certain conditions even during warm summer months. It'll cycle on/off even more during winter.

In your Ranger you should be able to hear the "click" when compressor kicks on/off. Open hood, Roll down window or open door, start truck, leave fan speed on low, then turn dial to Max AC. You should hear the click almost immediately.

If no click, grab your voltmeter, and check for 12vdc at the 2-wire plug on the compressor. Obviously use care around radiator fan.

12vdc present, bad compressor(or clutch). No 12Vdc, more troubleshooting necessary(most likely low freon or blown fuse).
 
The compressor will cycle on defrost. If it is not working, try tapping on it with a screw driver or small hammer. It could be stuck. I've seen it happen many times. If not, as someone else said, check available voltage at the compressor coil. If you have voltage there, then it is either a bad clutch and/or coil.

As a fair safe, if it low on R134A, then it will not engage the clutch. You could try putting a small can at autozone in to see if it works. If it does, then its a charge issue. Best solution to that is have a shop evacuate, vacuum, and recharge the system with dye.
 
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The AC runs (or should) when using the defrost mode for quicker defrosting. (many older systems didn't) The freon doesn't make anything cold, it absorbs heat which in effect, leaves cold. That part is for the cooling. But heat can be collect for other uses.
The system also contains some lubricant. So running the AC unit (compressor) in the winter makes for more efficient defrosting, and keeps the AC system lubed etc.
If the AC compressor is not kicking in, do the easy first like checking for voltage at the clutch pack connection. Fuse needs to be good etc. Also, if the freon level is too low which means the static pressure in the system is too low, there may not be enough in the system to actually run it. I had to put in almost a full can in the wife's SUV before the pressure switch allowed the circuit to complete for the compressor to operate. Then I continued to add (low pressure side) until I was able to obtain the correct amount needed. To little can frost things up as well as not enough. Oh, I had to evacuate the system because the valve needed replaced from leakage (not seating, so I pulled a vacumn then started adding freon (134-A) with new valve until enough activated the pressure switch which then allowed the clutch to engage to turn the compressor.
 
At 35 degree's, it may too cold for the compressor to kick in... Static pressure would be roughly 30psi, and the low cut off is about 25 and would kick back in 40-50??? or so. Compressor may come on briefly, then it would shut down for some time. As underhood temps rise, then the compressor should cycle more.
 
I like the way my 02 Accord is set up, the a/c automatically comes on when defrost or defrost/feet is selected (these are buttons with a picture showing window, and window/feet etc). The a/c button is separate below this, so if I don't want to run the a/c I just push the a/c button and presto no a/c running !!

Why this long explanatory post ? Because in the winter time I like the front window/feet mode best, as I don't like hot air blowing in my face, nor all on my feet... the from windshield/feet mode keeps the climate inside my car really comfortable, and there is no need for adjustments once the car is up to temp it is the perfect option in my opinion.

Honda does get some things right every so often, this option was one of them.. maybe the guy engineering this particular part thought the same way I think.
 
Originally Posted By: 1kickbuttranger
At 35 degree's, it may too cold for the compressor to kick in... Static pressure would be roughly 30psi, and the low cut off is about 25 and would kick back in 40-50??? or so. Compressor may come on briefly, then it would shut down for some time. As underhood temps rise, then the compressor should cycle more.


Where he's at, temps are sufficient to make the low pressure switch. He should be hearing the click of the compressor cluth engaging. But it appears the OP isn't providing much feedback so who knows? Maybe he took it in and it's already fixed.
 
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