A friend wants cameras front and rear on his truck like his hero. That’s an easy task. Plug and play.
Or so I thought.
If camera 1 in the front is plugged in to a 12v outlet, it works.
If camera 2 in the front is plugged in to a 12v outlet, it works.
So far, so good.
Now, since he wants minimal cutting, conversion, or changes we have to be creative.
He has a positive and negative wire coming directly from the battery to a couple of radios. Big stuff, like 12 gauge I think. Both have an inline 20 amp fuse. I tap into them, adding a 12V outlet below the dash. I plug in a 1 into 2 splitter, giving us 2 12v outlets to use down below, leaving the dash alone in case he wants to use his GPS or whatever.
When camera 1 is plugged in and turned on, we’re good. When camera 2 is plugged in, we blow a fuse. A 20 or even 30 amp fuse, just smokes upon plugging. The camera isn’t even attached yet. And the most confusing part is, the fuse in the plug itself is a 2 amp fuse, and it never blows!
Taking this cord to another car works fine. Hooking it up to another car, or my jump box makes it work fine. Only when tapped in to “mains” as it were, does it stop working.
It will blow a 30 amp fuse quick as a wink. The one in the splitter plug, or the +/- leads. You’d think there’s a short. But, I took it to my shop to experiment, and plugged it into a 12v power supply, and Viola! It works!
Why the hell is this this 12v plug and power cord blowing 20 and 30 amp fuses, while the 2 amp stays intact and works?
What am I missing here?