Radiator Fan Wiring Question

[DSMvroom]

Hi guys,

I'm installing a slim fan today and of course it only has one positive and one negative.

Searching has found that many people have had success with connecting both the ground wires to the ground of the fan, and both of the positives to the positive of the fan.

My question is, would there be any ill effects if I only used one pair instead of both pairs? I understand that one pair is for the low speed and one pair is for the high speed, but my fan only has one speed anyway. Comments?

 

[MrBoxx]

It would only be bad if you mixed up the different speed positive wires with a different speed's ground. i.e. Hi-speed positive and low-speed negative connected to positive and negative fan wires, respectively. Since the different speeds are run through separate relays, I don't believe the fan would come on correctly, though I can't be positive. I've got mine hooked up to both positives and both grounds, plus I rewired the relays so both fans come on at the same time. So far, things are good.