How to drive 4-pin fan
Connect +12V to red and 0V to black leave the other wires unconnected. If that doesn't work the fan is busted.

This is based on the assumption that this similar to the AFB series fans. (and every other common 12V tacho/pwm fan), I could't locate the AFC series on the Delta electronics web-site.

some of their other fans have blue as tachometer out and yellow as pwm in.