I've been toying with that idea for a while now, but yours looks good...guess you hadn't hooked up the fan motor by the looks of that open plug...curious to know how the wiring would work on my setup...since I don't have that much in terms of wires to work with...
Does this require direct wiring to the fuse panel (I remember a fan relay on mine that kept blowing)?
actually its kinda simple. though i think i may get a bigger fan. idk yet havent had any big heat days.
what i did was picked up a few things:
1x Thermostat to turn on power at set temp. (get adjustable one)
2x relays ~ Dual Pole type 30A(get what the fan draws on high)
1x roll of 10 guage wire (power to fan and ground)
1x roll of 16 guage for signal wire
3x packs of female conectors 10 guage
2x pack of female conects 16 guage
1x pack butt connectors 10 guage
2x pack vampire clips 16 guage.
1x 30A inline fuse
what you need to do is find a ignition power wire for the T-Stat's power, so it can send power down the signal wire, to trip the relays. I used the wire that runs to my cig lighter, as its setup for ignition on off.
baiscally, the thermostat comes on with the truck. when it senses heat, at a certain temp it send power down the signal wire to one relay. that relay is grounded, so it activates the switch on the relay.
Power from the battery (with fuse inline) goes into #30. when power from the thermostat is sent to the relay, it goes through #85 and the to a ground plugged into #86. this activates a coil, which sends the power from the #30 to the #87(not "a") and into the fan. #87 is plugged into the fan high wire.
now, this is what turns the high speed on. works great cus you can adjust it on the T-Stat.
now, for low, you run a wire from the positive on the ac pump, to the second relay #85. be sure to run a ground for #86 in this relay as well.
now heres where the first relay comes back into play. Run a wire from the #87a on the first relay, to the #30 on the second relay. this will now give the second relay power when the first one is not activated by the T-Stat. Now, run a wire from the low speed on the fan, to 87(not "a") on the second relay. What this does, is cycles the slow speed with the AC pump.
why you do this:
you must have a fan going on the ac condensor when the ac is running.
this setup runs the slow speed on the ac cycle, but if the T-stat senses high temp, it will disconect the slow relay and run the high until the temp drops, then bringing the slow back on and running it with the ac. Note: it will only run with the ac if its on. if the ac is not on, it wont run slow speed. .
if done correctly, when you start the truck and trun the ac on, the slow will kick on. if the truck gets too hot, the high will bypass the low, cool it and then return power to the low speed relay. if the ac is off and the temp is below the setting, no power will be drawn.
if you got lost in that heres a simple wire setup:
#30 is power in
#85 is signal in
#86 is signal out (or ground)
#87 is power out when signal wire is powered
#87a is power out when signal wire is not powered.
now, 87 and 87a could be switched depending on what kind of relay you get. meaning the off plug could be 87a not 87.
if you look at a relay, theres 2 plugs going one way, and 3 going the other.
the two are power out. of the 3 going the opposite way, the ones across from eachother are signal, and the one alone is power in.
any questions email
Clarke_n@live.com
Welcome Visitor! Please take a few seconds and 
