so my 02 Expedition has been nothing but problematic.

My current conundrum right now is I don't have any heat/defrost/a.c. in the front.
Resistor has been replaced, blower motor has been replaced, fuses seem to be fine. As far as I can tell I am not getting any power into the relay. Anyone know the cause of this or where to look?
The previous owner had installed an aftermarket radio and did a poor job of it.

I live in Michigan and no defrost is a problem.

 

"I want to find people that do this [bad stereo installs] and castrate them, because if they wire like this, god help us if they reproduce." -Aaron Cake

The following information is from the 1997 Factory Service Manual, 2002 may be slightly different but the logic is the same.

Are you receiving power at the relay's pin 86 from the interior fuse box (Fuse#24, 10A) when the Mode Selector switch in any position but off? Same with Relay pin 87 from the underhood fuse pin, (Fuse #23, 40A)?

If both of these are good, the relay's ground is the problem. The other possibility is that the relay is worn out after 14 years of use. Try swapping in a known good relay. If it's still not working, read on.

The Blower Relay's Pin 85 is a straight line to Ground# G200, which is shared with the Blower Speed Switch (which provides the blower motor's ground) and dashboard illumination. G200 is underneath the Passenger side of the dashboard and appears to be behind the kick panel. It has TWO ring terminals. If it looks CYAN, clean it with sandpaper or a dremel along with the sheetmetal that it touches when bolted down. Bare Shiny Metal is the goal here. Replacing the bolts with Stainless Steel ones is a smart choice too. Stock ones are probably M6x1.0, with a non-standard 8mm head.

 

Please define exactly what that means.

 

As in...things aren't getting hot or cold, the vents aren't changing from floor to vent to defrost, or as in the blower never blows?

 

Blower never blows. I have a new resistor, and blower motor in it. But no power is getting to them.

 

Here is the wiring diagram...start tracing.