Strange Blower fan problem

[jp450]

I did the searching and came up with nothing...

My 99 Sport's blower fan is messed up. The fan works in possition 1 (low) 2, 3,& 4. However possition 2&3 are the same fan speed... Replaced the resistor pack, switch and checked all the relays with no results... Any Ideas?

 

[budwich]

check the connector by measuring between the two pins for 2 and 3 .... actually all combinations.... they all should be open. while on the topic, I thought there was only "off" "low" "medium" and "high".... I assume you are referring to "low" and "medium".... not that it matters... I am not a long time Ford owner so they maybe difference across models that I am not aware off.

 

[jp450]

The off is selected on the vent selector knob. The lowest setting is almost totaly off but there is a ever so slight breeze coming from the vents...

 

[budwich]

you are right... my bad.... I don't know what I was thinking about.... too much sun on the tennis courts. Anyways, the check that I suggested is still valid....with the connector off.

 

[gijoecam]

Double-check the switch itself. Make sure it's got continuity through it.

Indeed, double-check the harness and connector. It may *look* OK, but may, in fact, be toasted.

Mine got to the point where it only worked on high, and the connector had melted and the wiring had corroded. The corrosion caused it to get hot, which melted the connector.

Pics are in the gallery linked in my signature. They're in the Explorer Pics menu IIRC.

 

[jp450]

I found the problem... It was the LG/W wire from the switch to the resistor pack. The resistor pack side was a little loose and coroded. A little push and wiggle was all it needed.... Well now I have a new switch and resistor pack. They should outlast the truck...

Thanks for the help!

Jeff

 

[gijoecam]

Glad you got it fixed!

I forgot to mention... You may want to pick up a new pig-tail anyways. The pig-tail isn't sealed, so the terminals and the wires themselves corrode, and that generates more heat, which causes more corrosion.... It's a vicious cycle. The new pigtail was about $15 IIRC, and all you had to do was strip back the bad wiring a bit and solder it in place.

Also, I filled the outside of my new pig-tail with silicone to help seal out the moisture that caused the problem in the first place, and packed the front face and the resistor pack with dielectric grease to completely isolate the connections from the elements.

-Joe