Need a switched power source to tap...
 

Looking to wire a device and planing on using a 4 pin relay...

After doing some reseach and looking at the fuse panel in my H3 not certain what to tap into.

Need 12v only when the key is on. Any suggestions?

Thanks!

Re: Need a switched power source to tap...
 

I used the acc outlet for 12 volts (or get it under the dash in trailer wires or under the hood).
I taped into the green/white ignition wire behind the wheel(comes down from the key)to switch it on only when trucks running.(to power fridge).

I first hooked it up to key foward and back(acc) but I had batterey issues.
I used the yellow wire that goes to rear wiper(to relay)

What are you installing ?

Re: Need a switched power source to tap...
 

[quote=fourfourto]I used the acc outlet for 12 volts (or get it under the dash in trailer wires or under the hood).
I taped into the green/white ignition wire behind the wheel(comes down from the key)to switch it on only when trucks running.(to power fridge).

I first hooked it up to key foward and back(acc) but I had batterey issues.
I used the yellow wire that goes to rear wiper(to relay)

Thanks 442!
Let me see if I have this correctly. Since I am looking for a switched on source you are suggesting the green wire/white tracer that drops down from column to tap from to activate my relay.

I have a 30 amp load off the other side of the proposed 4 pin relay for a fuel booster that currently runs on a manual switch:beerchug:

So did you do something similar for your fridge?

Those acc ports are on all the time and not good for the battery.

Regarding the green/white wire how did you tap in?:D

Re: Need a switched power source to tap...
 

Im not sure of the amps on the acc oultets I think one has more amps then the other(The dealer put a cig plug in my left one)
Only way to check is to see what fuse is used by looking at the fuse box)
I originaly had the fridge hooked up to the cluster that is capped off for the trailering brake that is located under dash to left of wheel towards the radio.
Easy to find and theres a 12 volt constant there.
When I hooked up a trailering brake I moved the fridge wire to acc oulet I think the lighter was 20 amps and the right acc was 15 amps Im not sure though.(taped into right one and I havent had a problem with the fridge yet)Im Kinda sure the + in the cluster is 30amps.

It doesnt matter that your power wire is constant it will be switched on and off by the relay. the switch wire(ign or ign and acc) isnt powerfull enough to run a device it just triggers the relay to allow 12volt wire to power device.



As for tapping into the green/white wire ,you could use one of those in line tappers at any auto store just get the correct gauge. that what I used at the acc plug and the rear wiper switch.For the green /white wire I just un did the electrical tape from that wire where the installer cut into it for my aftermarket auto start.

You could get the 12volt power wire off the battery if the wire is needed under hood,just get a eye loop and put it on the battery terminal(use a fuse as close to the battery as posible and make sure you leave the original terminal nut there and put the eye loop on top then use another 10mm nut on top of that. do not try to remove original nut it only loosens to remove terminal you cant get the eye loop under it without damaging the stupid set up of the terminals.
Good luck:beerchug: I hope I didnt over explain this ?

Re: Need a switched power source to tap...
 

Thanks for that 442,
Been probing around and going to run a block off the battery similar to your set up for my load side of the relay.
For the switch side source going to tap into the wire for the sun roof 12v which I do not have:beerchug:
This electrical stuff makes me crazy. Appreciate the sanity check!
BTW that is one clean battery top you have there.

Re: Need a switched power source to tap...
 

Old pic from 05 when i installed my airhorn.
I have a few more tap ins on it now.

W the sunroof is on a RAP circut.
It will stay on when keys in acc position and when key is removed,untill you open the door.
Im dont think thats a good idea for your install.


Remember think twice(or more if your like me) do once

List complete install when your done Fuel booster ?