Accessory wiring question
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Accessory wiring question
I am installing a hands free cell phone kit in my truck. It is the hard wired type. What I would like to do is wire it so that when the truck is off and the phone rings, the horn will blow. I am out of the truck at times and don't always grab the phone. I know this can be done, I know a company that does this to their fleet. The wiring comes with a hot, an ignition hot, a ground and another wire that attaches to the stereo system to auto mute the radio when a call comes in. My radio does not support this particular function. I am wondering if there is any way to tap this wire into the horn relay so that it honks with the ring?
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From: Virginia
When you get it all set up, take a meter and test the auto mute wire. Put the red lead on the mute wire, and the black meter lead to ground on the truck. See what you get when the phone rings. If you get 12 volts, you may be able to drive a relay with that signal, and let the relay contacts activate the horn circuit.
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From: Bel Air USA
I installed a hands free kit in my 93 F150XLT and used the radio mute wire to mute my radio. If I remember correctrly, (it has been a few years now), I used a relay to cut power to the radio when I receive or make a phone call. You could also use the wire to blow your horn but you would need to get a time delay relay or the horn would blow all the time you are on the horn. I believe that Grainger's would have the type of relay that you would need.
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From: Bel Air USA
You can actually drive a relay regardless of whether the wire goes from 0 to 12 when the phone is in use or goes from 12 to 0 when the phone is in use. You will still need a time delay relay unless you don't mind the horn blowing the whole time the phone is in use.
The wire will stay in whatever state it goes to while the phone is in use, not just while it is ringing.
The wire will stay in whatever state it goes to while the phone is in use, not just while it is ringing.
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Originally posted by kioolt
You can actually drive a relay regardless of whether the wire goes from 0 to 12 when the phone is in use or goes from 12 to 0 when the phone is in use. You will still need a time delay relay unless you don't mind the horn blowing the whole time the phone is in use.
The wire will stay in whatever state it goes to while the phone is in use, not just while it is ringing.
You can actually drive a relay regardless of whether the wire goes from 0 to 12 when the phone is in use or goes from 12 to 0 when the phone is in use. You will still need a time delay relay unless you don't mind the horn blowing the whole time the phone is in use.
The wire will stay in whatever state it goes to while the phone is in use, not just while it is ringing.
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From: Oregon
The official term for what you are trying to do is called, "horn honk". I know, sounds kind of hocky, but that's it. Like, "I'm installing my own horn honk feature and I need a timed relay, do you have one?"
Try searching, "radio horn honk."
Try searching, "radio horn honk."
