Where to pull switched 12V power from?
Thread Starter
TECH Apprentice
Joined: Sep 2003
Posts: 304
Likes: 0
From: Lake Cumberland, KY
Where to pull switched 12V power from? I'm racking my brain trying to figure out which fuse in the underhood fuse block I can pull switched 12v power from. Right now my radio stays on ALL the time and I have to manually turn it on and off. I think it keeps sending a signal to my amp and keeps it turned on because if I don't drive it for a day or two my yellow-top is generally drained. I have a wiring harness from a local stereo shop with all the relays to make everything plug up to factory but it has to draw switched power from somewhere! ANY HELP??? 
thanks!
thanks! 
Sounds to me you have wires hooked up wrong.
Mainly I belive you may have the power wire from you radio connected to the continues wire, instead of the ignition wire.
When connecting a radio their is two wire that are very critical so your radio isn't on after you turn off the car with the ignition.
That would be the power wire, and the igniation wire. Switch these two wires.
I would go to an auto parts store and get wire tester -not sure the proper name of this too- but it allows you to test if the wire is getting juice, with or without the ignition switch on the on position.
fix: you wired your radio wrong, wire the right wires.
Mainly I belive you may have the power wire from you radio connected to the continues wire, instead of the ignition wire.
When connecting a radio their is two wire that are very critical so your radio isn't on after you turn off the car with the ignition.
That would be the power wire, and the igniation wire. Switch these two wires.
I would go to an auto parts store and get wire tester -not sure the proper name of this too- but it allows you to test if the wire is getting juice, with or without the ignition switch on the on position.
fix: you wired your radio wrong, wire the right wires.
there are many places to pick up an ignition on wire, these guys are right u definitly have your 12v radio source hooked to a constant 12+. this will drain any battery over a time period, and eventually it can cause damage or complete failure to your alternator due to heavy loading and constant charging demanded from it. bak to ignition on, think of all the ignition on sources in your car, what only works with the key in the ''on'' or ''start'' position? then tap the power from that accessory (not ground of course) the way to do this is with a tool called a light voltage testor. hook the clip to a good ground, start poking into the wire with the key on, if it lights up, turn the key off, the light should go off. if it stays on it is a constant source.
