A/C stuck ON and battery dies

[NateTheShake]

First off I'm a brand new member here. Through my various internet searches this site had the most comprehensive list of troubleshooting threads for the Ford Explorer/Ranger. So hello!

Here's my issue(s) in my 2005 Ford Ranger 4.0L:

A few days ago I noticed a pretty loud whirring sound coming from under the hood while driving. It sounded like the vehicle was running the A/C and the fan was engaged although I did not have the A/C turned on. After a few miles I pulled over to check under the hood and the A/C condenser was covered in frost and when I turned on the A/C it was freezing cold immediately. All well and good, but the A/C wasn't turned on.

So I decided to drive a few days and see if the problem continued. Well it has and yesterday I came out of work to find my battery was stone cold dead. I popped the clutch to get her started and came home to do some searching. As of this morning the car is even dead...er than yesterday (no battery power whatsoever).

The symptoms are as follows:

1. A/C system running regardless of A/C being on or off
2. Frost completely covering the A/C condenser
3. Fan running continually (which I assume to be a result of the A/C)
4. Dead battery after sitting for over a few hours

I've been trying to figure out how all these symptoms relate or if I am actually having more than one problem at once. I have an extremely busy work schedule so I'm tempted to drop it off at a repair shop, but I'd rather take a day of vacation to figure out what the problem might be before I get bent over backwards by a shop trying to repair random crap just to troubleshoot.

Any ideas guys?

 

[dynamite196]

I'd take a look at the a/c relay, there should be a box with a bunch of fuses and relays right near the battery. Do you have a hynes or other service manual? They generally specify how to test relays, or maybe somebody else here knows, but you could also try swapping it with another one you know works (say the cooling fan relay) and see what happens.