I'm converting my 91 geo tracker to use an electric fan,The fan will be a puller,same as stock. I know that black is ground and blue/green are positive.I know that the high speed setting on the fan is when both green and blue are hot.I'm just wondering which wire is the low speed setting, or if it even matters.

Thanks in advance.

If you have a 12v car battery (pulls a good deal of current to power fan, so battery works with testing) connect the fan to it and see how it goes; make SURE it's pulling air and not pushing it. You'd be better off letting it run at full speed as it'd kick on, cool radiator quickly, then go off. Some cars use a giant resistor to lower speeds.

 

If you can only get it to turn on at low speed, that might still be enough. In single fan set ups, I believe the higher speed kicks on when AC is activated as that creates a heavy load on the engine, which needs more gas at idle to compensate for and not stall out, which creates more heat.

 

Hook it up, and watch your temps. I'd suggest connecting a temporary light to the fan circuit so you know if/when the fan is kicking on. You can also run a slightly cooler thermostat 180 degree vs. 195, and the system will open the thermostat sooner, making it run cooler and less fan-on time.

Edited April 8, 201610 yr by Bushwick

either wire by it self will run the fan at low speed, I haven't found any difference in which one to use.

 

Of course I'm wiring them in to my 3/4 ton Chevy so I'm using their max potential.

The last time I used this fan was in the car in my sig, and with the EJ it had enough of an alternator not to care so it was full throttle.Now i'm using it on a 91 geo tracker and its alternator is only good for 55 amps,but the fan only has to cool 80 HP of 1.6L fury...