I’ve got a 2002 Escape, 130k on it, fairly light duty, and I live in GA so it’s still really clean and no rust or anything. I’ve got an intermittent AC problem. The AC works perfectly, dumping out ice cold air, but only like half the time, the other half of the time it just blows air. I’d say there is a pattern that it’s more likely to cut off in stop and go traffic, or if I sit with it idling, but that isn’t always the case. It works so well when it works, I’m guessing it’s either related to the clutch, a relay, or a sensor somewhere, but I’m not sure what to do next.


Anybody have any suggestions, or anything that can at least help me rule out anything and get me closer to the problem?

 

Being a 2002 it's 15 years old. A/C systems will leak refrigerant over time.You may be a little low on refrigerant, thus no cooling at low speeds. Also, since the systems are charged under a vacuum, any lost refrigerant can be replaced with ambient air. Since you're in GA., your ambient air has more moisture due to humidity. Any moisture in the system can cause the orifice/expansion valve to freeze up causing no A/C until it unfreezes. For basic maintenance, I would have the system recovered, pull a good vacuum to rid the system of any residual moisture and then put a fresh charge of refrigerant. Add no oil as you don't want to slug the compressor with liquid and lock the compressor up.

 

I've still got the same issue I originally posted. My AC goes warm when I stop moving. In the last week I've done some investigating.


Last week I did have the system checked, evacuated, vacuum tested, the re-filled at a shop. We were in FL at the beach, I was in and out in under an hour, I saw the sign and pulled in.


Apparently it was slightly low, and he replaced the schrader valves, suspecting one of them could have been seeping. It may have been, but regardless I still have the issue and I'm 300 miles from the shop. He did see a bead of water, I don't fault him in any way.


Now that I'm paying close attention to it, if I maintain highway speeds, the AC works indefinitely.


I've now realized the radiator fans are only operating at low speed. I tested the fans by bypassing the relays, and they both work at high speed.


I tested the relays, all three work perfectly.


There is the 4th relay that I saw is some sort of medium speed relay. I didn't test that one since I couldn't easily get at it.


So basically, I've zeroed in that the fans not going to high speed is the problem.


I have no idea what's causing them not to go to high speed.


I've read some threads pointing me to the CTS,


My temperature gauge is always right in the center, I watched the tem with the cluster in diagnostic mode for a few days and it shows a pretty constant reading too, I forget what it was, 200s somewhere.


I've been keeping an eye on the coolant. The level has been perfect. I mention that because about 6 weeks ago the coolant level light has been coming on, which I think is just that the float has gotten heavy triggering the light. I can't imagine it's related because I see no correlation between the AC kicking off and the coolant level light being on.


I'd read something about disconnecting the CTS, which causes the fans to come on, but I think that was addressing them not coming on at all vs them not going to high speed, and I couldn't see which speed it put them at, or if that could cause other issues.


Can anyone help me zero in on how to get those fans to come on at high speed?


Also, does anybody know the different criteria for them coming on at the different speeds? Temps? AC On? Coolant level? Speed lower than?

 

:-) I checked the CTS to see if it was covered in crud, it was, and the o-ring was dried out so it was dripping when I put it back in. I replaced the CTS and just ran it in the garage for an hour and 15 minutes, and it's been dumping out 47 degrees the whole time, and the high speed fans kick right on and off with the AC switch.


I didn't test it between testing and re-seating all the relays, I didn't really have a choice since it was leaking, but I'm optimistic that it's fixed.

 

So oddly it stayed on at an idle all that time, I tried it again later in the day in the blazing sun too, no issue. The temperature reading was right around 217 the whole time. I ran a few errands at the end of the day and it ended up cutting off again. The temperature while driving hovers around 232, and it was probably about 30 minutes in that it cut out after having been stopped for about 30 minutes.


The symptoms today seem to be that it gives me 30 or 40 minutes, then fades if I stop, but comes back.


The only relay I didn't check was that medium speed one. I'm wondering if that's the root of it.

 

Alright, I still need some guidance on my AC issue. My suspicion is that it's tied to the electric fans not running fast enough when they need to. I've confirmed that the fans themselves do function at all speeds by jumping the relays, bench tested the relays, checked the fuses, and confirmed that the resistor has continuity. My coolant temperature sensor gasket was dried up and dripped after I looked at it, so I replaced the sensor. A few weeks ago I did have the system evacuated, vacuum tested, recharged, and the schrader valves replaced. I was looking at the wrong numbers on my temperature reading, it runs between 94 and 98 or so celsius using the cluster diagnostic mode. The AC works as long as I'm driving, and oddly if I don't drive at all. If I drive, then stop at a light the AC goes warm within a couple of minutes. It confused me that when I started the car cold, and left it idling for over an hour not having been driven at all, the AC ran ice cold the whole time. Any suggestions appreciated.