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flosho · Posted: Sun Jun 17, 2012 12:33 am Post subject: Need some wiring help... kthx

Does anyone know what this wire belongs to? Its Green/White and *was* connected to something but I can't figure it out.

It kinda goes with the a/c fan switch.

Right now my radiator fan doesn't turn on automatically.

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Grenadiers · Posted: Sun Jun 17, 2012 1:26 am Post subject:

Checking my '80 Euro wiring harness, looks like the terminal for the fog light switch. Does it have a black/white wire bundled with it? I attached my switch to the wiring, and the patina of the male/female terminals matched perfectly. Haynes calls it a green/white wire though.
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'83 944 Track car.
'88 924S Track car.
'89 944 Turbo
2004 Winnebago Vectra monster RV
2012 Jeep Wrangler
2014 Kia Soul
2001 Ford F350 powerstroke

flosho · Posted: Sun Jun 17, 2012 1:58 am Post subject:

Buwani 931 · Joined: 31 May 2004 Posts: 308 Location: Napa California

Is it really long? Like long enough to reach to ashtray light?
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1980 931
That's thirty minutes away. I'll be there in ten.

leadfoot · Posted: Sun Jun 17, 2012 8:27 am Post subject:

potentially, rear window defogger switch,
connects between
switch and defogger relay,
think there's a relay mounted near the heater control panel on the inside of the centre console just above the radio, and another one back a little further towards the firewall. I've had two cars which had "mystery" but you could tell they were factory positions the relays were mounted in. Think they just ran out of room on the relay panel to mount everything.
Stu
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

flosho · Posted: Sun Jun 17, 2012 10:33 am Post subject:

I *THINK* I've figured out what it could be.

In the wiring diagram (Page 297 of Haynes) it has a Green/White wire that connects to a resistor (which shows a red wire on the other side of the resistor).

fuse 3 has a red and red/brown wires from it the red/brow goes to the cooling fan relay and the red wire goes to the resistor and then to the cooling fan relay.

Any ideas on how to wire up an aftermarket fan to come on by itself?
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[This Space For Rent]

leadfoot · Posted: Sun Jun 17, 2012 11:42 am Post subject:

Ok, 2 options,
If your ecu has thermotime built in you wire the trigger circuit to pull negative,
The other option is to use a standard switch and the thermo switch in the rad, or both ecu and rad thermo for when the car is parked, as you'll lose power to the relay when ignition is switched off.
All the big ceramic resistor does is to rop voltage supply to power circuit to save draining the battery
I found if you can have the ecu vome on at 82/83C the by the time you seitch the car off it will spike up to 95C and the cool for approx 5mins and turn off. Having the fan bypass the ceramic resistor runs the fan harder but turns it off quicker. Below is the pin config for relays. Think of them as two seperate circuits, when one is completed(control) it energises the relays other circuit(power) and supplies the part with power, this way you have smaller wiring for control and heavy wiring for power and the relay is rated to supply the amperage required. Fuse comes before relay so if you draw too much power it blows and protects the more expensive relay.
http://www.mp3car.com/the-faq-emporium/117895-faq-relays-how-they-work-and-how-to-wire-it-up.html
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...