Aftermarket radiator fan wiring

[Mulvi]

Hi all as the title suggests im about to wire some slim aftermarket fans for the twin td04 vr4. Would like to know how to go about this. The fans I have are 2 wire and ive noticed the stock plug has 3 wires two larger and one smaller. Im a sparky and I have a hunch the old module on the fan controlled the speeds and was just fed a constant 12 volts and was fed a voltage signal from the ecu. Would like to know what other peoples solutions have been. cheers

 

[pretzil]

Yeah, the small wire is a signal from the ECU, if it is cut then both fans run at full power as a fail safe (I ran mine thru a switched relay as an override to turn the fans on)
You can just keep the original hedgehog control module and tap your new fans into the 2 wire outputs that went to the old fans.

If relocating the hedgehog make sure it is in the flow of the fan air still.

 

[Mulvi]

Funnily enough the hedgehog has been sold along with the stock fans. How do you suggest I control the fans? Or do I just need to go and find one just to keep it simple

 

[pretzil]

I'm sure there are aftermarket fan controllers available, but keep in mind I'm pretty sure the factory one also gets a signal to turn on when the AC condenser needs it.
Might just be easier to track down a factory one