AC shuts off
 

Sorry if this was asked before but a search didn't reveal anything.
AC works and blows cold until the engine gets hot enough for the radiator fan to kick on. AC shuts off and I get hot air.
I replaced the radiator fan last fall but didn't notice the problem until this hot weather. Any ideas would be appreciated.

Re: AC shuts off
 

The A/C is set up to cut out if the engine water jacket temperature is "too high". So my question would be this: "When the A/C cuts out, just where, EXACTLY, on the scale is the water temperature needle?"

From what little information you gave, it sounds to me like it (the A/C) is operating normally but your car is overheating. The fan should NOT come on and run almost anytime the car is moving - mine doesn't, even in 95F or so weather - unless, of course, I'm sitting still for a time. (Ok, fine, the fan runs, but not at any speed you can hear it running, if I'm moving at all.)


Are you getting any warning lights on the dash when the A/C cuts out? If so, what lights are coming on?

Re: AC shuts off
 

check the heater control valves, they are plastic and brake, =AC gets hot once engine warms up

Re: AC shuts off
 

Jim is right, your A/C may not be cutting out, if the duovalve is doing it's usual "stick open" thing, then once the engine gets hot, you have heat, even if the A/C is cooling the air, it then goes thru the heater core and if the valves are open, you get hot air.


The issue can be a sticky valve or valves OR it can be fractured solder connections between the two circuit boards of the climate control module in the dash.

Re: AC shuts off
 

The radiator fan runs as soon as the AC is switched on, that is my understanding. So if it doesn’t then something is wrong. You can hear the AC compressor switch on and off.

Re: AC shuts off
 

Thanks for suggestions everyone. I'll check it out this weekend. Really appreciate it!