PWM radiator fan controller

[terrydmorgan]

I'm wiring my car now and got to the point where I was going to hook up the wiring harness for coolant fans using relays to effect a single speed fan controller. However, I ran across a posting on Lateral-G that goes into great detail on how to use the ECU and a pwm controller (from a C6 Corvette) to produce a variable speed fan. The fan speed is controlled by inputs from coolant temp and AC pressure. Aside from mounting the PWM controller, you only need to add an AC pressure sensor with 3 signal lines to the ECU, and the ECU programming will have to be changed. For a Vintage Air system, you'll still want to use their binary switch to turn the AC compressor off when AC pressure is too high or too low, as no one has figured out how to control the compressor using the ECU. Should be a very reliable setup since it relies on GM production parts. And it's not terribly expensive. The PWM controller is about $100.

I'm going to get started on mine soon.



If you're interested, here's a link to the Lateral-G posting: http://www.lateral-g.net/forums/showthread.php4?t=40215