[Red_Stang06]

I have a 2006 Mustang. A few days ago, I noticed that the first 3 speeds of my 4 speed heater fan switch did not work. Position 4, which is HIGH works great. Does anyone have any experience with fan switches? I am hoping to find that there is something simple solution and not have to replace the switch.

All comments welcome.

Mary

 

[stars]

There’s a fuse in series with the resistor string that lowers the fan speed (see diagram). In all likelihood that has blown. The whole resistor assembly will probably need to be replaced. Sorry for the bad news.

 

[Red_Stang06]

Thanks so much. This is a start. Is it very complicated to replace? Is it accessable under the dash or does the center section (where the switch is mounted) have to be removed to replace the resistor pack?

 

[stars]

The resistor assembly is actually located inside the plenum area and uses air flow through the vent system to stay within its operating temperature range. I've not actually removed one from an S197 so regrettably I can't give more details about gaining access to it. There's a good chance it will unscrew from the outside of the plenum. I'm guessing you'll have to remove the center consol to get to it, though taking a look underneath the dash can't hurt.

 

[stars]

Found the diagram (in the link). Looks like it won't be too hard to replace.

Ford Service Manuals - REMOVAL AND INSTALLATION

 

[ChrisLav]

My girl had the same problem in her car. 1,2, and 3 didn't work but 4 did. I know we cleaned out the cabin air filter and something else.


I'll ask tonight for ya but if you wanted you can try replacing fuses and cleaning the cabin air filter in the meantime.

 

[TimmyandRene]

Our 06 Mustang has had the same problem, we were able to replace the part fairly easy, and not expensive, about $20.00, but now about 2 months later it has gone bad again! Anyone else having these issues?

 

[Emonesmith2]

Our 06 Mustang has had the same problem, we were able to replace the part fairly easy, and not expensive, about $20.00, but now about 2 months later it has gone bad again! Anyone else having these issues?

The same thing happened to me and my 08 mustang.
After I installed the new piece, it worked great for a couple months. Then it started making an aggresive clicking noise when it first started up. Now it stopped clicking, but only works on 4 again. I guess I'll try replacing it again and see if that solves it!

 

[wjbertrand]

Betting the fuse is OK since the high speed works, probably just the resistor assembly. These will overheat and burn out if your air flow is inadequate - clogged cabin filter, fan not running at correct speed, kinked or obstructed vents. Tip: don't run your fan with all the vents shut.

 

[Coosawjack]

In the '03 and '04 Marauders FORD had a lot of problems with the "Blower Control Module" since it had poor solder joints on a LARGE transistor mounted to the heatsink!!
Simply removing the "BCM" and re-soldering the transistor fixed 90% of them......give it a whirl.....got nothing to lose!!:grin:

 

[s197gt]

"These will overheat and burn out if your air flow is inadequate - clogged cabin filter, fan not running at correct speed, kinked or obstructed vents"

So while you're in there, replacing the resistor, why not remove the blower motor and check it's squirrel cage for foreign objects. And as stated above, must also check the cabin air filter (in cowl area/underhood/firewall area.)

Blower motor here:

Ford Service Manuals - REMOVAL AND INSTALLATION

Both the resistor and blower motor are each incredibly easy to remove and replace or reinstall on this car...each being directly above the passenger side footwell area.

And there are various YouTube videos relating to cabin air filter replacement, also cowl drain grommets, water leaks...all related to same area of car under hood.

Example here: http://www.allfordmustangs.com/foru...301555-pics-vid-2005-dash-water-leak-fix.html