Adding a battery disconnect under dash
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3rd Gear
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Adding a battery disconnect under dash
Hello, my dad has a 15 or 20 year old f150, 6 cylinder. It has a small battery drain we can't figure out. I would like to put a switch under the dash. Any idea what switch I should use and what wire to run through fire wall to the battery? Thank you very much.
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From: Virginia
Do you want to walk through finding the drain?
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3rd Gear
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I just dont want to fool with it anymore. I want to put a switch on and be done with it. I just didn't think finding a simple switch and running a couple wires would be easy. Not sure why finding a switch is this hard.
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From: Virginia
Not sure what you want to switch. If you have found a smaller wire under the hood that makes the drain go away, you could put a switch on it. But most main feed wires are fairly large, at least 10 gauge. Instead of running the power from that point into the trucks wiring, that power is now going to be running all the way into your switch, leaving your switch and running all the way back out to it's original point of origin. You have to make sure you run large enough wire not to create too much voltage drop. And your switch needs to be large enough to handle the load. Depending on what circuit you are trying to kill, it can be over 30 amps if it involves the blower motor, the lights, the wipers, etc. which are all on during a rain event sometimes.
And then you have fusing. If the wire you want to intercept comes directly from the battery, it MUST be fused. The battery is capable of many many amps. If something happened to your new wire and it rubbed to a piece of metal, it can turn red hot very quickly and catch things on fire if it's not fused very close to the battery. The factory used fusible links for this purpose.
And then you have fusing. If the wire you want to intercept comes directly from the battery, it MUST be fused. The battery is capable of many many amps. If something happened to your new wire and it rubbed to a piece of metal, it can turn red hot very quickly and catch things on fire if it's not fused very close to the battery. The factory used fusible links for this purpose.
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