Having connected MIL-spec wire to all six wires (three on the fan and three on the plug) we shrunk everything in 3/8” Raychem shrink wrap and used adhesive shrink to seal off the ends. We ran both sets of wires to the passenger side where our relays are mounted and zip tied the wires neatly out of the way.
Despite using standard (cheap) automotive-grade wire with relatively weak insulation, the 99+ fan has a decent gauge wire given its 40 Amp draw:
|Chassis Side Wire Color||Fan Side Wire Color||Description||Gauge Wire|
|Dark Green (middle)||Brown/Red (middle)||Low Speed Fan||14 awg|
|Light Green||Brown||High Speed Fan||12 awg|
The NOsparc® arc suppressors are wired as drawn in the diagram earlier. The Red wire connects to the hot side which always has power while the Black wire becomes hot once the relay triggers it to switch on. This is when the Arc Suppressor does its job to eliminate arcing to prolong the life of the relay.
The NOsparc suppressors are also mounted with a ¼” gap for better insulation.
Wiring the power, ground, triggers, and NOsparc was a bit time consuming given that each wire was crimped, soldered, and shrunk. This was as elegant as we could make it.
Now the wiring is finished. The main power and ground from the circuit breaker travels along the bottom of the radiator shroud and up to the relays before following the new wires to the center of the fan motor. The factory plug’s ground and low/high fan wires travel to the relays across the radiator face and act as triggers to send the power to the fan motor via 10 gauge MIL-spec wire.