To ground or not to ground?

[HugoBox]

I posted awhile ago about a problem with a bow mount (24 volt) Minnkota when I hook up the dpeth finder to the universal sonar. My brother who is a bit smart than me figures that because we have the dpeth finder wired directly to the ignition battery (12 volts) but the transducer for it is hooked up to the T/M wich is 24 volts we should ground the ignition battery to the negative side of the 24 volt set up. Does that make sense? Also, not sure if my description makes sense, if not I can further clarify.

thanks - erik

[BoxMN]

FYI - it is US1 not US2. I know US2 do not need to be grounded between starting and TM batts. Thanks for any info, we are trying to ge the front sonar working without making the motor go goofy...

[marine_man]

It would be worth a shot I guess to connect the two and see what happens... you could use a one half of the jumper cable to connect the two - that, or connect the depth finder wires to the trolling motor battery via jumper cables from where they would connect to the starting battery to the trolling motor battery temporarily.

marine_man