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siiirhd88
12-22-2007, 04:47 PM
Thanks to Tom locating a vendor source I now have heated windscreens for the wife's 109. I still haven't had any ice or frost to see how well they really heat up, but they seem to do a good job clearing up the typical fogging. I also added a heated rear window and washer to the previously added rear wiper. The windscreens have conductors at the top and bottom edge, that are not completely hidden when installed in the windscreen frame. The wires exit the glass along the bottom edge, and the angle glass securing strip must be cut or drilled to clear the wires. I used a Jeep Cherokee heated rear window 'smart' relay for the circuit, which was wired to dulplicated the Jeep circuit. Pressing a momentary pushbutton energizes the circuit for 5 minutes, then shuts off. I also added a green indicating light to show the circuit is energized.

Bob

pygmypotomus
12-22-2007, 06:36 PM
That's awesome! I'd love that but I think I need to focus on functional wipers first. :)

scatterling
12-22-2007, 06:55 PM
Bob,
nice looking dash...who is the vendor for the glass? cheaper than RN?
thanks Neil

siiirhd88
12-22-2007, 08:26 PM
I will need to check with Tom P before I post the vendor info. We had three sets shipped from England. The cost per SET, with shipping, was cheaper than a single windscreen, less shipping from RN. I don't know how these screens are in comparison to a factory screen from RN, however.

I did order a Defender heated rear window from RN, due to a much higher shipping cost if sent from England. The box for a rear window would have been much larger, and couldn't be delivered to the house.

Bob

siiirhd88
12-23-2007, 02:42 PM
This is the heated screen relay and circuit as wired in the 109. I'm not sure what I bungled in the wiring, but in the 109 the screens come on automatically when the ignition switch is in the 'on' position. Pressing the momentary pushbutton shuts off the screens, until the button is depressed again.

The relay can be found in a mid 90s Jeep Cherokee, behind the dash to the right of the instrument panel. It is the red color relay, plugged into (I think) a red socket. The relays are available new from Napa and the dealer at around $40. I picked up a handfull of relays from my nearby Jeep junkyard, for free.

The relay has five 1/4" flat lugs, numbered 1 through 5 with very small numbers. #1 is power from the relay out to the heated screens. #2 is wired to ground. #3 is power in from the momentary contact switch. #4 is hot power in from the battery circuit, normally the solid brown wire in an unaltered Series harness. (does one exist?) #5 is relay power from the ignition circuit, normally the solid white wire. The power to the momentary switch is also connected to the ignition circuit. I used insulated 1/4" female spade crimp connectors for the relay wires, and added fuses to the ignition and battery power to the relay.

Bob

http://i26.photobucket.com/albums/c120/SIIIRHD88/ScreenRelay.jpg

http://i26.photobucket.com/albums/c120/SIIIRHD88/ScreenRelay2.jpg

http://i26.photobucket.com/albums/c120/SIIIRHD88/ScreenCircuit.jpg

crazyfish
12-24-2007, 12:48 AM
If it comes on when the ignition comes on, then shouldn't the switch being between the ignition and 5? I can't find a good diagram of the workings but it still looks like a SPST relay. I wonder if you could hook up the idiot light to 3.

siiirhd88
01-02-2008, 10:48 PM
We had a hard frost the other morning, with thick ice covering all of the glass. After starting the truck and powering up the heated screen and rear window, I scraped the ice off of the passenger windscreen and side windows. By the time I had the other windows scraped clear, the rear window was melted clear and the windscreen was a layer of wet ice that the wipers instantly cleared. The ice I had left around the edges of the passenger screen was still evident when I reached home, but the drivers screen was completely clear.

I had noted that when in the rain and the screens fog, the drivers screen becomes fog free in about two minutes when the passenger screen is still not fog free after 20 minutes, even with the blower on.

Whoo Hooo ! A mod that works well!

Bob