PWM radiator fan controller

[TBART70]

Found out that the time delay relay needs to have 12 volts going through the accessory side to work. I will have to put a high amp relay in and use the time delay to control it. I wanted it to control the sensor but it has 5 volt reference which is not enough to power the capacitor.

Got it all together and it works good. 90 second delay off on the fans when car is off. pwm works well no full blast on the fans unless I hit the bypass switch.