Location of 12 volt ignition source- under hood or under driver dash

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I'm installing a Redarc DUAL INPUT 40A IN-VEHICLE DC BATTERY CHARGER and it requires a 12 volt ignition turn on wire.

Where would I tap into a location, either under the driver dash or driver side under the hood? I would prefer not to tap into any fuse box. I would rather tap into
a 12 volt ignition wire or a location that has 12 volt ignition power.
 
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given that you need it as a signal wire you could tap it just about anywhere, i would try to find something close to wherever the charger is going to be mounted then check an ewd to see whats available
 

Broski

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40 amps well need a Dedicated line from the battery and most likely a relay from from a ignition source to turn it on.
I’m one banana when it comes to wiring someone with more experience May chime in
 
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It's going to be mounting near the driver side 2nd row seat. So anywhere from that location under the channels under the doors under the dash through firewall and under the hood. Where would you tap into this?
 
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40 amps well need a Dedicated line from the battery and most likely a relay from from a ignition source to turn it on.
I’m one banana when it comes to wiring someone with more experience May chime in
The 40 amps is power going to the batteries. Those will have 4 awg. The 12 volt ignition wire is just a signal turn on so it gets a 10 awg.
 
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given that you need it as a signal wire you could tap it just about anywhere, i would try to find something close to wherever the charger is going to be mounted then check an ewd to see whats available
I have the EWD but it's it's written in language that is like Greek to me
 
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I have the EWD but it's it's written in language that is like Greek to me



not to sound too condescending or like a smart ass but start there, toyota does a really good job of laying out whats in the book and how to read it. if you look in the front pages of the ewd the how to use this manual is an excellent guide to using the book. it breaks down how to read an ewd and shows examples of what your looking at and the glossary will have symbols that youll see.

the book isnt going to give an exact tap here, youll have to probably do some voltage checks to make sure that you have a 12v source thats going to suit your needs (hot all the time, hot key on, hot in run)
 
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Cig lighter is keyed power, have been using it as my signal for a keyed power fuse panel without issue for many years.
 
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Cig lighter is keyed power, have been using it as my signal for a keyed power fuse panel without issue for many years.
Good option, but that's not quite under the driver side dash (it's more central) and I've made that into a 12 volt constant already.
 

Broski

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Theirs switched power under the passenger front seat at the rear heater.
Mine rear heater was removed so it was a perfect place to grab key on power.
 
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Thanks. I have some of these, but as I mentioned in my post, I would rather not tap into a fuse panel.

if your worried about overloading the circuit i would see what the draw on the charger is and then choose an appropriate circuit that has a high enough amperage or something that you dont use often. i would also second the cig lighter as an option since it is fairly easy to access, hot key on, and you can run your signal wire under the rug from the center console. you could also look at the dome light wire for door the rear door switches but thats hot all the time and may not be the most ideal if you were looking for power with key on only
 

TomH

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There is an unused three wire connector on the drivers side tucked up in the corner by the vent. One of the wires is switched power.
 
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Do US vehicles have this power box in the engine bay (circled yellow below)? It's an easy place to find ACC/ON switched 12V power.

InkedFZJ Power Box.jpg
 

Broski

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Broski

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There is an unused three wire connector on the drivers side tucked up in the corner by the vent. One of the wires is switched power.
This is good to know, I have not seen this connector ! but well be looking for it !
 
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Wiper motor if you dont have the power outlet box under the hood. This is where most IGN power is sourced here in AUS for dual battery controllers.

EDIT : sorry just saw your mounting in the rear wagon space, fuel pump +ve feed then
 
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Theirs switched power under the passenger front seat at the rear heater.
Mine rear heater was removed so it was a perfect place to grab key on power.
Yes, that is a possibility if I have to use the passenger side.
 

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