Cockpit Side of the Wiring
Now that I have buttoned up the engine side of things I am going all in on the cockpit side of the firewall wiring. As I dig deeper and start laying things out I keep bumping into items spread across the three installation manuals - F5 Chassis Wiring Harness, Ford Control Pack Installation and the F5 Coyote Installation Manual.
I have several questions about integrating the RF harness with the Coyote harness. Some are related to what appear to be redundant circuits, and some are just those I can’t seem to wrap my head around. I am hoping some of you who have gone through this process can shed a little light. I am pretty comfortable with wiring but the directions provided are throwing me a curve ball. So here goes:
- Fan circuit. F5 instructions state to connect the RF blue fan wire to the Coyote PDB orange wire if I plan to use the engine fan control. I am assuming they mean the engine computer fan control. With that said, why use the RF wire at all? The PDB box has a power wire for the fan (orange), an associated relay to power the fan, and to me, connecting that blue wire seems totally extraneous and unnecessary. I am also using a PWM fan controller, so I don’t need the fan thermostat wire either.
- Ignition wiring. Specifically, the blue trigger wire. I am going with the “Setup A” wiring schematic from the PDB instructions. I am using an ignition key switch with a separate push-button start. Is it still necessary to connect the blue trigger wire from the RF harness? Again, seems redundant since its only function is to tell the starter solenoid to engage. Maybe I am missing something.
- RF harness power. I am pulling power off the ignition side of my cutoff switch to a bus bar. My intention is to then connect the necessary RF hot wires, which would normally go to the starter solenoid. There are three called out – Battery Feed, Alternator Feed and Ignition Switch to Solenoid. When I trace these back it looks like the Battery Feed powers the RF fuse panel, the Alternator feed should be coming from the alternator and the Ignition Switch feed powers the Bat + side of the ignition switch. Does this sound correct?
- Alternator Feed – my Coyote harness has a plug for the alternator built into the PDB harness. The Ford instructions indicate simply connecting C102A, and that’s it. Page 92 of the F5 Coyote installation calls out installing the “Chassis Harness Alternator Red Wire” to the alternator post. Aside from the stubby one in the main harness I mentioned in question 3 above, there is no engine-side heavy-gauge alternator wire in the RF harness that will come close to reaching the alternator. Do I simply connect a 6 or 8 gauge wire to the HAAT side of my cutoff switch and run it out to the alternator? Seems simple enough but that’s what worries me. What am I missing?
Thanks in advance.