ac fan-fuse 27 pass comp keeps burning out

[david ranger]

Due to Eddo;'s remark I decided to unplug the AC compressor connector GRY/WHT+BLKbefore installing the external relay.
Now the fuse does not blow anymore.

Ofcourse I have no working AC.
Guess the short is in the compressor itself ?

 

[david ranger]

Found 2 vids covering a delaminating coil causing a short..

 

[RonD]

Problem is fuse 27 has no connection to AC clutch

AC Clutch is powered by fuse 25 in engine fuse box
AC Clutch relay is powered by PCM Relay and fuse 11 in engine fuse box

Fuse 27 is a "trigger voltage" so it was most likely being shorted to ground INSIDE the PCM, probably the black/yellow wire, its always a ground if AC pressure is OK

 

[david ranger]

RonD, you were right. Drove around 2 weeks with AC compressor clutch unplugged but then the fuse started blowing again.
So no easy fix by replacing the clutch coil and i have to install that external relay.

Has anyone the pin out diagram for easy location of wires (41,69 and 86) in the PCM bundle?
2005 3.0 V6
Cannot find it online.

 

[Eddo Rogue]

RonD is always right lol...the D is for Da man!

 

[RonD]

You would need a 2005 Ford Ranger EVTM(electric troubleshooting manual) that Ford sends out to Dealer shops every year for every model, its part of the Shop Manual set

Like this one: https://www.ebay.com/p/22012217399?iid=362817950270

 

[david ranger]

Luckily FORD put the number at the first pin and last pin of each row (1~27, 28~52,etc) so that helped a lot.
Finally installed the external relay and problem solved.

Thanks guys for all the help. Greetings from a cold car in the HOT Caribbean!

 

[RonD]

Good work

Thanks for the update

 

[david ranger]

And the fuse blew again after 14 days.
So maybe there is another short circuit somewhere.
I changed the fuse and now it works again.

I am waiting for the clutch coil to clear customs due to a long delay.
It is a shame not to try it as i have the part already.

 

[RonD]

The 14days is odd

Yes, might as well change the coil, but its power comes from fuse 25 in engine fuse box, not 27 in cab fuse box

I would be tempted to use a 15amp fuse in place of the 10amp, just to see if its a direct short thats blowing the fuse not an amp draw issue, the wiring can handle 15amps, so no "smoke show" lol, but up to you

The Blend Door is also powered by this fuse 27, and it was a common failure on Fords, although can't say shorting out was a failure point, but its an electric motor so certainly could be the issue, drawing too many amps now and then

 

[david ranger]

Thanks. I will swap it out for a 15amp next time it blows.

 

[RonD]

Do you remember adjusting the TEMP knob at the time it might have blown, or does it pretty much stay on COLD all the time, lol

The TEMP knob controls the Blend Door

 

[david ranger]

Thanks Ron D.
I unplugged the blend door actuator a long time ago so that may not interfere anymore.
I tried 15 and 20 amps with no result.
They burn within minutes.

So i will change the coil. See what that does.

 

[david ranger]

I sold the car WITH the problem for the next owner.
Thank you guys for all the help.
It is really appreciated.