AC Always on, unless switch is off...

[Fredness]

Searched and found nothing.
I don't remember it always doing this, but I think it is an issue.
I think it was AC was on in AC, Max AC nad defrost only. Now it is on in every setting except "Off". I've pulled the #2 relay fromn the underhood power distro box, since we aren't using AC at the moment. Any ideas? Sounds like the controls are worn out/shorted.

 

[Fredness]

Can anyone with a '97-'98 verify thatt he AC is off during normal vent operation and only on during AC ans defrost operations?
Thanks!

 

[Turdle]

Mine cycles with every selection, except off.

 

[Fredness]

OK, maybe it isn't broken, it just never worked right from the factory!
I'll post my fix, should be good for a couple MPG's!

 

[Hoppy]

Your AC will come on in every position except off, floor or dash vent.

 

[briwayjones]

The compressor will cycle on AC, MAX AC, Defrost, Floor/Vent, defrost/floor and floor. Not vent though. So everything but vent(panel).

 

[Dopler174]

The only time is will be off other than "OFF" and the listed above, will be when the outside temp is below 42 Deg. I read it in a Ford owners manual.

 

[briwayjones]

The only time is will be off other than "OFF" and the listed above, will be when the outside temp is below 42 Deg. I read it in a Ford owners manual.

Mine cycles when it's below 42 degrees if I have it on defrost and such. It cycles to remove humidity from the air. And to keep the compressor lubricated.

 

[rwenzing]

This thread is about 2nd gen Explorers with manual A/C and the A/C compressor logic is as follows:

AC compressor operation allowed:
Max AC
AC
Vent/Floor
Floor/Defrost
Defrost

AC compressor operation not allowed:
Vent only
Floor only
Off

In addition to the manual controls, compressor operation can be disallowed three other ways.

Low A/C system pressure (cycling switch)
High A/C system pressure (pressure cutoff switch)
Engine in power mode (PCM)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If you don't like the factory A/C logic, it is easy to install a switch to interrupt the purple wire from the HVAC controls. This allows you to turn the compressor off in every mode if desired. (It is a good idea to run the compressor for short periods even when not needed for cooling or dehuimidification of the interior. This circulates the compressor oil and keeps the seals lubricated. That's why the factory setup has it running so often.)