Edit: Rather than create a new thread, I've edited this one to create a How to:
I removed my AC a while back so I have the AC pressure switch shorted with a paper clip to keep the radiator fan working properly.
Since then, I've always thought it would be neat to re purpose the AC / ECON switch in the HVAC as a switch to manually activate the radiator fan when sitting in traffic.
I was thinking one way to do this was with the now disused AC pressure switch. But I'm not sure where the switch is connected. I took a look at the wiring diagrams and I THINK it goes the the radiator fan relay?
Anyone know any better or could help me track this down?
20 Gauge wire (closest colours I could find were blue and black). Can see the wire extensions crimped on and heat shrunk.
Once the extensions were crimped on, I covered the new wires with plastic split coil and fed them through the firewall along with the engine harness. From there, I fed it under the airbox, behind the glove box, behind the radio, and then over the lower air duct toward the switch. The route doesn't really matter, and I may end up changing it down the road.
I do plan on acquiring some oem Toyota 2-wire connectors from Dr. Tweak which I'll solder in-line near the ECU so that I can easily disconnect this new harness without having to get at the switch on the driver's side.
The factory switch. Im going to have some decals printed to cover the original text to match the new purpose of the switch.
Also, due to the nature of the Rad fan relay, I decided to install the switch upside down, otherwise the switch action would have been backwards.
I rewrapped the harness using a combination of 3M electrical tape and "X-treme Tape". I used the 3M tape in the same areas as OEM to help bundle the wires together. The X-treme tape I used overall to wrap the sections of old electrical tape I removed. It's supposed to be good from -50C to +260C and something like 8000V. Time will tell how long it will hold up for. This was my first attempt at wrapping an engine harness.
Last edited by Corey
on Sun May 10, 2015 3:13 am, edited 4 times in total.