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Discussion Starter · #1 ·
I'm not electrical savvy. But I didn't think I was a dummy. I bought a boss audio system for my Sport glide. So the instructions offer 2 wiring options, one with a switch and one using a relay. So I tried to wire it with a switch. I watched a couple videos and thought it would be do able. So, I bought an on and off switch. 30 amp. I ran a wire to the positive side of the battery. I hooked the negative side of the wiring to a post on the side of the frame. Looks like a ground bank. I tested it with a test light. It has a few wires hooked in to it. Nothing hooked to wires past the switch. As soon as I connected the Negative battery cable it started smoking, melted the Pos and Neg wires from the switch back to the battery. Any Ideas what I did wrong? The switch is labeled, Earth, load and 12 volt 30 amp. I had the ground to earth, Hot to 12v. And a wire out to the stereo connector. Which has only 2 wires. Red and black with a red stripe. Nothing was plugged in to them, they did not melt. I did have the ground and the black with red stripe hooked together on the earth connector of the switch. Thanks in advance.
 

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Not having the schematic or directions i am guessing. Was the switch a lighted switch? I assume so, as switches do not use a ground unless they are a lighted switch and you never connect a red stripe wire to ground, even if it is a black with red stripe, so curious as to what each end of the red stripe wire was connected to. Also best advice i can give you is to ALWAYS put an in line fuse on the positive wire. If you had wires coming off the switch, perhaps one was touching a ground if the switch was wired correctly.
I also would opt to wire it through a relay and not a switch, just my opinion. Have the relay close (powered) when the key is in the on or run position. Also 30 AMP is an awful lot of current for a radio. Does it have a high powered AMP? 30 seems a bit high. What does the radio label say for amperage? Start with an inline fuse that size between the switch and power source/battery.

Take a very close look at the switch…you wired positive and ground and made the connection to create a short and everything melted. Always use an inline fuse to protect the electrical system or you will learn a very expensive lesson.
 

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Discussion Starter · #3 ·
Not having the schematic or directions i am guessing. Was the switch a lighted switch? I assume so, as switches do not use a ground unless they are a lighted switch and you never connect a red stripe wire to ground, even if it is a black with red stripe, so curious as to what each end of the red stripe wire was connected to. Also best advice i can give you is to ALWAYS put an in line fuse on the positive wire. If you had wires coming off the switch, perhaps one was touching a ground if the switch was wired correctly.
I also would opt to wire it through a relay and not a switch, just my opinion. Have the relay close (powered) when the key is in the on or run position. Also 30 AMP is an awful lot of current for a radio. Does it have a high powered AMP? 30 seems a bit high. What does the radio label say for amperage? Start with an inline fuse that size between the switch and power source/battery.

Take a very close look at the switch…you wired positive and ground and made the connection to create a short and everything melted. Always use an inline fuse to protect the electrical system or you will learn a very expensive lesson.
Nothing was plugged in to the stereo end. Only wires to the switch. Yes the switch is lighted. All three prongs are the same color, one long one in the middle. there is a 7.5 amp fuse between the switch and the radio. That's what the directions showed. I was thinking I wired it wrong. But I just went out to check. I touched the wires directly to the pos. and Neg. on the battery with no issues. Then flipped the switch and it lit up. Should I put the fuse between the battery and the switch? I will have to run new wires anyway.
 

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Yes, between the battery and switch. A lighted switch does explain the ground…it is not needed for the switch to work, it is only used to allow the light to work. Just to be sure, if you have a multimeter, ohm between the 2 positions on the switch that is the load and 12V and make sure you have continuity with the switch on then turn the switch off and you should loose continuity.
Be wary of the ground as it will show continuity between the ground and the 12v lead through the light bulb so it is easy to confuse them and I suspect that happened and caused the melting of wires. With the meter set to lowest ohm setting with the switch on, you should read 0 ohms between load and 12v leads and you will read something a little higher than 0 between the ground and 12V. My advise is not to connect the ground just yet. Get everything working first. This helps a avoid the risk of reversing the wires and is the best approach. That is because it can be tricky with a lighted switch unless you are experienced…
 

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By the way, given wires melted, i would not use that switch as it will have premature failure. Sure bet it’s is damaged internally but may seem fine right now…it isn’t…
 

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You can stick with a 30 Amp switch…just put in a fuse that aligns with the radio current demand. The fuse is what is important. You want the switch to be able to carry what ever demand you place on it but fused to protect everything…including the switch
 

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Discussion Starter · #8 ·
You can stick with a 30 Amp switch…just put in a fuse that aligns with the radio current demand. The fuse is what is important. You want the switch to be able to carry what ever demand you place on it but fused to protect everything…including the switch
Thank you. You have been very helpful.
 

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Note: only connect ground wires to the black wire lug NOT the black / green wire lug. The black/green grounds are for non switching circuits only.
 
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