I just got a switch for the rear defrost for a 91-94 Explorer,
Engineering Number F37B-19A328-AA
Part Number F3TZ18C621B
Supposed to be self contained with timer...just need power.
I plan on installing it in my F350 for mirror heat that I just installed.
It has 5 wires which means there is more to hook up than power in, out and ground.
Anyone have a schematic or the color codes for this?
How about rating for the switch? The mirrors only pull 1.4 amps total.

Here are the colors...

2 large (14g)
Brown w/ Lt blue stripe
Grey w/ lt blue stripe

3 small (18g)
Purple w/ Orange stripe
Lt Blue w/ Red stripe
Black ( I assume it's ground)

And Pics....







Thanks all!

 

Here's the circuit, have no idea in the switch rating but surely the mirror is less than the rear window grid.

 

It's hard to tell from the diagram above, but fuse 11 appears to be a 15-amp fuse so the switch should be good for at least that much current since there is probably a chance that the rear window defrost could be the only thing on that circuit that would be operational when the defrost circuit could short out, therefore all 15 amps could momentarily flow through the switch before the fuse would blow. Continuous current of the rear window defrost is probably in the neighborhood of 5 amps, you should have no problem using the switch for your mirrors.

-Rod

 

Wow! Thanks guys! That is exactly what I needed. Now to find the time to mount it....wire it....etc.

 

Hi, I bought the switch but it didn't come with the wiring/plug. Would you happen to have a part number for that?

 

I'm afraid I don't. I got lucky and mine came with it.
You can do searches like in Google or eBay for pigtails or..... Salvage yard or..... Just connect direct to the back of the switch. With the pics n diagram you should be able to see what goes where. At first I was thinking of connecting direct to the back of the switch until I saw the part with the pigtail.

 

does that switch fit in that pill shaped blank on the dash (used for adjustable pedals) on
the super duty trucks?

 

I dont have adjustable pedals on my truck so I couldnt tell you on the fit. I installed mine next to the ESOF switch. Measured the body of the switch. Made a cardboard template then traced it to the dash and drilled and routed with a dremel

 

the original part numbers you posted showed one of these. ive seen it in 80s tauruses. it looks like the same shape of the blank hole on my 03 dash.

now doing some more research it looks like theres a crown victoria switch that would pop right into that hole. i have a ram phone mount base right next to my transfer case switch.

 

What you have to watch for tho is the timer. The one that I used has it built in to the back side.
If yours has it built in too then now I wish I had gotten one of those.