Windstar A/C has a mind of it's own?????

[kjlouie]

My 2003 Windstar's A/C will be on when I start the car, when the A/C was off when I turned off the car the day before "and" vise versa. I.E. when I had the A/C on the previous day, when I start the car the following day, the A/C will be off. It's annoying in the winter when I don't use the A/C and I start the car the next day, the A/C is ON and I have to turn it off everytime! Anyone have any suggestions?
Thanks in advance.
Kingman

[bdahl385]

Just be sure to turn your AC ON before you turn your engine OFF so that your AC will be OFF when you turn the engine ON...

I can't believe I just said that - Seriously, you have a most unusual symptom and don't have a clue what would cause this. Does it happen 100% of the time? Please post back if / when you find the cure, this should be very interesting...

[tomj76]

So you're saying that at startup the A/C doesn't behave according to the selector switch position?

Is this the only function that follows this strange behavior? In other words, does the fan operate if the selector is in the off position? Does the air come out the right vents for the position of the switch?

[kjlouie]

Thank you both for such a quick reply.
Isn't it the weirdest thing? When the Windstar is started, the A/C is always the opposite of what it was when the car was last on. It happens 100% of the time. If the A/C was ON when the car was turned OFF, the A/C will be OFF when you start the Windstar next time! (and vice versa) It only happens when the Climate Control is in one of the "on" position, i.e. A/c , A/C Max, Upper vents, Lower Vents, Defrost, etc. If the climate control knob is in the "off" position (12 oclock straight up), the A/C light on the button doesn't go on and the A/C won't be on...

Any help or direction would be appreciated. Everything works fine, except it's a hassle to remember to push the A/C button on or off when you start the car.......
Thanks for your learned suggestions.
Kjlouie

[tomj76]

I think the A/C controls on your '03 operate differently than the A/C controls on my '96. I have no light indicating the status of the air conditioner, and no button to operate it separately from the climate control knob.

It sounds like the button you're talking about toggles the A/C operation independent of the knob position. Is that right? Is the button a mechanically latching toggle (like the rear window wiper button) or is it electrically toggling w/o a mechanical latch, like the O/D button on the transmission?

[bdahl385]

I have a 2000 so would think the controls would function similar to the "posessed" 2003. On mine, the A/C switch is a separately mounted momentary contact it appears to me. It physically does not stay indented when on and then out when off. The A/C function toggles as you depress and release the switch. A very dim orange bulb glows to show status.

I wonder if there could be a pinched wire from this A/C switch or such that is grounding when the motor torques during engine startup. It could also be a grounding or power issue that causes the climate control module(s) to interpret the engine start voltage spike as a change in the switch position.

You would really need to understand electrical diagrams and read the schematic for this switch and what it connects to to troubleshoot it. One of the more interesting problems no doubt.

[tomj76]

The good news is that it is highly repeatable, so with the right knowledge and tools it should be easy enough to diagnose.

[searcherrr]

I'd call TAPS. lol

9 times out of 10 with electrical its the moving part. Wires haven't changed or moved in years. I bet its the switch itself and the contacts have worn or corroded. I had this happen to me on my rear panel windows and had to replace the switch. There was no ghostly stuff like this afoot, but just that they would work sometimes and other times not.

And yes.... I agree always TURN OFF A/C before cutting off ignition. Always start Ignition with A/C OFF. Your vehicle will thank you.