I want to wire this so that the relay only kicks on when the key is in the on position. My question is, where should I tap into for the relay power?
One option: The aforementioned harness from the HondaSXS store. Plugs inline behind the 12v socket in the dash:
Quick and easy KEY ON Accessory power source for your Honda Pioneer. PLUG-N-PLAY No Splicing of wires. No Tapping of wires. 3ft lead easily reaches anywhere under the hood. This kit plugs inline with OEM harness and provides a 12v positive lead. Use this Key-On Accessory wire to run the...
store.hondasxs.com
Another option: Use the correct sized
fuse tap (aka add-a-circuit) and the appropriate rated fuses on the 15A ACC fuse in the OEM fuse box under the hood. It's the same fuse that the above harness would get its power from. See
this post for a pic of which one.
You might also consider installing a
DPDT switch so that you can choose, with the flip of the switch, if you want to energize the circuit only when the key is on OR even if they key is off. Best of both words.
If you're going to be running more accessories, lights, etc., you might want to do a quick search on the forums for two things: Installing a dual battery and isolator kit and/or installing a continuous use relay and multi-circuit fuse block where you hook up most/all your accessories.
Here is a great video by forum member
@RobSparre covering it all in great detail.
Welcome from MI.