Hey what’s up guys I’m new here and having some issues with my 1999 2.5 5 speed ranger. Basically started the other day driving down the road and noticed my speedometer stopped working and my turn signals as well. Once I got to work I looked and found the #10 fuse had popped. Replaced it and everything worked fine throughout the day and then the next morning same thing happened in the same location in my neighborhood and did some research and people said it was speed sensor or turn signal switch. Replaced both and everything worked good the rest of the day. the next morning I had the same issue heading to work again. Then I noticed that it was only when I turned my ac off that it would blow the #10 fuse on the side of the dash. Tested a couple things and it’s only when the ac is switched from any of the ON positions to the OFF position that it pops. If I go from OFF to ON everything works as it should.

In the last month or so I’ve done some maintenance stuff on it but nothing pertaining to the AC besides moving the compressor
when replacing the head, head gasket, timing belt,, and p/s pump but I only unplugged the compressor and moved it over a bit. Checked the plug on it and everything looks fine. Just frustrating to say the least lol. Has anyone had any issues along the same lines? Or any ideas for me to try? Thank you.

 

Welcome to the forum

No, this is a new one

Fuse 10(7.5amp) powers several things
Speed servo
GEM module(partly)
Shift Lock(automatics only)
Blend door(temp control door)
Flasher(turn signals)
AND
Function selector for AC control <<< as you may have guessed this would be most likely cause of fuse blowing

On the back of the panel there is a Grey/yellow stripe wire that comes from fuse 10, it is only used for AC which is on in ALL setting except foe OFF, PANEL, and FLOOR, any other setting like panel/floor has AC on, just FYI
The Grey wire sends the 12v from fuse 10 out on a Purple wire to the PCM(engine computer), pin 41, the PCM is what turns on the AC compressor

Fuse 10-----------(grey wire)------------------------AC selector switch------------------(purple wire)--------------------pin41(PCM)

The selector switch is a dual layer switch, so it is grounded on one layer to activate the Blower relay and blower speed
If there is a short between the two layers then fuse 10 would blow when switch shorted to ground, so its not AC on or off its switch position
I would see if fuse blows when you have it on FLOOR(AC is off), then turn it to FLR/DEF(AC is on), then turn it back to FLOOR


Also adjust the TEMP setting to see if fuse blows, the Blend Door motor was an issue on all Ford cars and trucks, but didn't blow fuses just stopped working

 

Ok that hat makes sense then. I’ll give it a shot when I take off for lunch and have a little time to play with it. Thanks!

 

Just got the chance to mess with it. Fuse doesn’t pop unless switching from MAX A/C or A/C to anything else. So I’m guessing that would mean my selector switch is faulty then?

 

Yes, that would be my guess as well.

You could test it with ohm meter once its out

Replacement on Ebay is about $60

 

Picked one up from a local scrap yard for $30 and that fixed it so far. Thanks for all of the help/info. I’ll comment back if the problem comes up again.

 

Good work

Thank for the update and hopefully "the fix"