How to: Blower Motor Resistor Replacement (Fan only works on high!)

[PurpleMystique]

Recently, the heat/air fan on my sister's '99 Zetec ATX started only working on high, no matter where the fan speed knob was set. Instead of paying $75/hr for a mechanic to troubleshoot and fix this, I fired up CEG and found that it is a common problem. My local Ford dealer had two of these in stock, I believe the price was around $16. I noticed a lot of "where is the blower resistor" threads, so I thought some pictures could help.

It's located in the front passenger footwell. It's an awkward place to get to, let alone take a picture of, so I tried to take several. In this picture, the tan piece you see is the center console, and the part we're looking for is the white plastic part with the four-wire plug facing the firewall:

Mine was held in by a single torx-head screw, it wasn't too difficult to get out. If you don't have a torx bit handy, an appropriately sized flathead should work.

Here it is with the resistor pulled out:

Here's what a bad resistor looks like:

Somewhere along the line, Ford redesigned this part. Here's the old one compared to the new one, you can see that the plug is rotated 90 degrees, but it's not a problem:

Here's the new one installed:

Once you manage to cram yourself into the footwell somehow, replacing this part takes all of five minutes.

 

[Scorpion8]

Any way we can get this "How to" re-contented for reference?

 

[ghent96]

The pics in this thread are broken, but I've recently done this repair myself, and will try to "refresh" this old thread with new info and pics. From what I've heard, these resistors meltdown rather frequently.

The hardest thing is probably just finding where the blower motor resistor is located at. Get into your passenger seat footwell. Look up towards the blower motor, on the airduct that feeds to/from that blower motor, which lies against the front of the footwell (the firewall), you'll see 4 wires running into a rectangular plug, in a white rectangular piece of plastic. Only 1 screw attaches it.

Pictures coming soon.