Anyone know exactly how our fan controllers work?

[MalcolmV8]

I'm installing a more powerful fan in my car with a shroud. A 98 Lincoln Mark VIII fan to be exact. I'm trying to decide on how to wire it.

My first thought was just take the low speed circuit from the fan controller and have it activate a relay and turn on the fan. Nice and simple.

I'm really not concerned with two speeds but if there's any possibility I'm open to it.

So with that does the low and high speed circuit from the fan controller work at different voltages? Or are they both 12 volt outputs that just run different windings in the motor of our stock fan that spin at different speeds?

Could I just wire the low and high speed circuits together (set to come on together in tune) to supply additional current to this fan which draws more and eliminate adding an additional relay? Or does the fan controller turn off the low speed output when the high speed output turns on?

So many questions... if anyone is overly familiar with the fan controller and can save me some detective work please chime in.

Thanks
Malcolm

 

[ShadowDrake]

I'm installing a more powerful fan in my car with a shroud. A 98 Lincoln Mark VIII fan to be exact. I'm trying to decide on how to wire it.

My first thought was just take the low speed circuit from the fan controller and have it activate a relay and turn on the fan. Nice and simple.

I'm really not concerned with two speeds but if there's any possibility I'm open to it.

So with that does the low and high speed circuit from the fan controller work at different voltages? Or are they both 12 volt outputs that just run different windings in the motor of our stock fan that spin at different speeds?

Could I just wire the low and high speed circuits together (set to come on together in tune) to supply additional current to this fan which draws more and eliminate adding an additional relay? Or does the fan controller turn off the low speed output when the high speed output turns on?

So many questions... if anyone is overly familiar with the fan controller and can save me some detective work please chime in.

Thanks
Malcolm

This one is coming off the top of my head, this is what I would do:

If I'm not mistaken the ECU has two pins it uses for LSF and HSF. I'd just use those (ground trigger) to power new relays for your high speed and low speed fans. The little fan controller relay or whatever it happens to be does some magic and drops the voltage to the fan. It generates a pretty significant amount of heat in operation so I think it's just a resistor bank.

But if you're looking to replace all of that anyway just skip the whole thing and use the pins at the ECU to drive new (bigger) relays.

 

[MalcolmV8]

The new fan is single speed. Only has two wire connections. I think I'll just use the current ECU/Fan controller to trigger a new relay and be done with it. Nice and simple.