Air conditioner goes on and off


1996 Grand Voyager; 167,000 miles

AC worked fine until a year ago when mechanic “charged it” since then I moved out of state and AC continues to work intermittently.

The fan works but the air will go from cold to “not cold” seeminly when I hit a bump … seems like an electrical problem


If the mechanic had to charge it up last year, chances are your low again. Have it checked to make sure. These systems don’t stay leak free forever, and this van is 12 years old. Probably has a few very slow leaks in it.


Hopefully you also fixed 100% of the leaks when you “recharged it.”


thanx knuckles, but I prob’ly wasn’t clear.
The air will be cold and fan works then the fan continuing to work but the air is no longer cold.
The mechanic in CA said they checked it out and there were no leaks
last summer a mechanic here in Pittsburgh said there were no leaks and suggested replacing the entire unit
Any ideas?


2 mechsanics said there were no leaks
fan works fine but air temp will go from cold to "not cold"
Some times (today) the AC was fine all 3 times I used the car


There are so many possibilities but I’ll give you one experience: My car would push out cold air except when I stopped in traffic, then it would go warm. As soon as I was on my way again the cold air would come on beautifully. My problem was two fuses which protected two large fans which are used to cool the radiator and the cooling coil. Fuses were replaced and have never failed again.


Craig and Busted Knuckles are correct of course about the leaks. If the system was recharged then it was leaking. Where do these mechanics think the refrigerant went? Nobody stole it.
You can safely figure a 13 year old vehicle with 167 miles has a leak or two.

As to the compressor possibly going on and off here, the first thing I would want to know is what the system pressures currently are. If the system is slightly low and the pressure is hovering close to the cut out point then maybe a bump is nudging it over the top.

Other possibilities could be a faulty relay, compressor clutch coil or connector, dashboard fan or mode control switch, faulty pressure switch, etc.
About all that can be done is go through the circuit connectors and perform the wiggle test on them while noting if the compressor is kicked on and off from doing this.


thanx chums, I’ll check the fuses