I'm looking for some help. My young and exuberant son just bought a 76 T-bird. Been sitting in a barn for several years. Anyway, it has an old Audiovox CD/Radio and USED to have an amp in the trunk. I am confused by the remote turn on wire that is supposed to come from the head unit. The best Audiovox could do is tell me that the wire is either pink or blue! I don't want to start any fires or melt anything. There are some stray wires in the trunk that are carrying current. One measures 7 volts DC and the other about -2.5 volts with the car off. Whether either of these is the Remote on-off or the original power feed to the old amp, I don't know. Any advice will be appreciated! Thanks.
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enough to be dangerous
When the radio is on you should have 12 volts. If you can not find the wire for it you can tap into the ignition wire in which will only give you 12volts or power only when you turn on the ignition. Hope this helps.
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Sound Pressure
You know you have the right amount of pressure when your eyes start to water! Now you've got Juice!
The remote turn on wire turns the amp on and off with the head unit (radio). Now the aftermarket audiovox head unit should have wire colors similar to this
https://www.the12volt.com/request/request2.asp but on the back of the head unit the remote wire is usually white and blue. Now on some older head units they didn’t come with remote turn on wires. In this case you would tap into a switched 12 volt source, such as the ignition. Now for the existing amp there should all ready be a remote turn on wire. It should have no power with the radio off and or car, and should have +12 volts with the radio and or car on. Depending on how the remote wire was set up, off the radio or ignition. If you cannot find a wire in the trunk that has a switched 12 volt like that. Then I would suggest you pull out the head unit and try and locate a blue/white wire. And test it for + 12. There also might be a blue wire now this could be the antenna trigger wire. However in the past I have seen where it is the remote turn on as well. If you find only a blue wire, test it for +12 volt with both the radio and or cd/ tape. If it loses voltage when in CD/tape mode then it cannot be used for the remote turn on lead. But to sum things up in the trunk you need to find a wire that has no voltage with the car/radio off and 12 volts with the car/radio on. If all else fails then I would tap into a switched ignition source and run a new wire to the amp.