What is best way to tap 12v ACC for multiple items/relays on FJ40

[zerotreedelta]

It's a horse apiece...I'm picking up what you're putting down.

I only like the fusible link as insurance against any abrasion on the feed between the battery and the secondary panel - typically those are heavier gauge, and they can make a tiddly bit o' heat if it happened to get pinched and grounded out.

Does depend a bit on where the box is planned to be and how long a run you'll have - the shorter the run, the less risk of course.

 

[45Dougal]

Relays should get their juice directly from a fused battery or added power distribution box. However, for switching them on and off, using the ignition switch like @ToyotaMatt suggested is a good one. Relays take like 0.1amps or less to switch, so triggering a few relays from the ignition switch is not a big deal at all.

Agreed, 100mA is nothing through the key switch (although relay is always active with the key). Maybe I misunderstood Matt's arrangement; I didn't see the relay there..
Late night reading..

 

[Last Flight Out]

Super lazy edit, but typically you'd want to put the toggle switch on the "signal" side, and not the load side. It's also frequently more common to switch the ground signal to the relay instead of the 12v, just as a ground wire is safer to run to the switch than the hot. They're generally a four terminal block - solenoid ground, solenoid 12v, 12v supply, and 12v load.

Alternatively, you could put the toggles in each leg of the green "ACC" line headed to each relay.

It's not on the diagram, but you'd likely want a section of fusible link between the battery and the new fuse box.

View attachment 3277997

Thanks @zerotreedelta - Ive never done a switch to Ground signal....that is an interesting idea. Curious - why is it "safer" to go this way vs 12v? Is it the idea around running a hot lead into cabin of car for potential contact with metal; potential shorting out?

And final question (Ill add fuse from batt to secondary block, as I forgot that)....is it ok to split one ACC switch signal as shown? I assume that really has no bearing on load, etc as it is simply a trigger to close the solenoid.