HELP electrical ?

I have a 24 volt system on the scratcher and Saturday about 6 hours running my bow mount motor my hummingbird and radio quit working, so tried to power it up came on and right back off! checked both motor meters had 2 of 4 battery lights on both bow and tiller. it was time to leave so no worries got to ramp and all worked but came home and plug battery into on board charger, sunday same thing but I still needed to fish so on water repair began hooked up hummingbird to start batt and continued to fish till I left!? any idea on y? low voltage? I should add no fuses were blown thanks in advance hummingbird is brand new

1. Sonar units should not be connected to trolling motor batteries because of the potential for RFI. Connect to the main battery with a fuse as close to the battery as practical per your owner’s manual.
2. The charge indicator lights on trolling motors are not accurate or very useful. Get a digital multimeter and keep it in the boat.
3. It’s not surprising that you would discharge the battery low enough to cause sonar problems after 6 hours of fishing.
4. Per the chart below, don’t go under 50% charge or you will shorten your battery life.

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I ran 12 gauge wire from the new Humminbird on the console all the way back to the starting battery & put an inline (3A) fuse on the pos wire, a foot from the battery connection. Same thing for the Humminbird on the bow. No problems. I saw the scratcher 2 out there Sunday. I couldn’t hack the crowd so I went searching and found a few.

thank you guys!! I will do that and i have had a inline 8 inches from pos> now I just hooked it to start battery. thanks again for the help