Battery Question in a Phoenix.....Take 2

[Eric521]

Ok replaced my cranking battery with a new X2 Northstar. But my boat is doing the exact same thing...voltage showing 9 when graphs are on and I trim motor and when I go to start my motor, one of my graphs turn off. Any ideas, I just spend $400 on a battery that I didn't need.

[DEFMP]

I know you're going to cringe when I say this, but I prefer my boats this way and have done two now, but I always hard wire each graph to the cranking batter to ensure I know exactly how my units are powered. It also reduces interference, especially at the bow from the trolling motor.

[Eric521]

Well it's been fine for 2 years and it just started. I'm pretty sure my graphs are direct wired. To me it's a voltage problem somewhere.

[DEFMP]

Well it's been fine for 2 years and it just started. I'm pretty sure my graphs are direct wired. To me it's a voltage problem somewhere.

Unless you wired the units to the batteries, the factory doesn't do this. Also, how are you measuring the voltage? I believe you need to measure at the battery and also measure at the unit connection, and if there is a difference then you have an issue in between(obviously). This is what hard wiring eliminates, if there is a difference, then your one wire is bad, so no need to dig around and see what the units are powered to.

[Eric521]

I'm measuring by the volt meter on my Lowrance. Getting ready to put a digital meter on the battery. My dealer installed all graphs and they hard wired them.

[DREWTICK]

Does you graphs turn off with the main power switch? if factory wired they will, check the voltage on the back of the main switch. the graphs may also go through one of the circuit breakers on a 2015, a bad breaker will cause the voltage drop to the graphs. so first read voltage at the battery, then at the switch, then at the graphs.

[kry29]

I would direct wire your graphs but the only thing I would think you could do is check voltage at your battery, then check voltage at the console before it ties in to the switches. If that's good, check voltage at the switch for the graphs and check it where it comes out of that switch. If that's good check it at the back of your graphs. Somewhere in there you should find the drop. My old boat had the same type of problem and I never found the cause. I ran new wires to the fuse panel and direct wired the graphs. Everything still worked ok but it would always show a low voltage or cut the graphs off until I direct wired them. You can also check to make sure something isn't pulling power when it's not supposed to

[DREWTICK]

if they hard wired them, check the voltage at the inline fuse for each graph and see if its close to what you get at the battery

[Eric521]

Ok digital meter on battery ready 12.5. Lowrances at the console readings are 11.8 and 11. I have 2 units at console. Start trimming motor up and down and digital meter on battery goes to 12.1 while console units drop to 10

[DREWTICK]

Ok digital meter on battery ready 12.5. Lowrances at the console readings are 11.8 and 11. I have 2 units at console. Start trimming motor up and down and digital meter on battery goes to 12.1 while console units drop to 10

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defiantly look for a inline fuse and check there

[haus9393]

If the fuses are good I would pull new wires for each graph. You might have an issue with wiring you can not see.

[DREWTICK]

also check if they only ran one wire to the battery and tied all the units to it , it may be to small, you can run one 8 to 10 gauge to a fuse box in the starboard rod locker and then run 14 gauge to each unit

[TritonJT]

Sure you don't have an alternator problem?

[Eric521]

Ok here's what I done....ran new separate wires from both console Lowrances to the battery with in line fuse and that fixed the low voltage reading on the units. While doing that I noticed my big positive wire from the battery to the master switch was loose at the master switch which may have been my problem.....now I'm wondering if I should unplug the power on my unit when I'm charging my batteries. One Lowrance on my console I leave on there all the time.

[GBhoss]

I have a separate cutoff switch for my graphs.... Battery to cutoff switch. Cutoff switch to units with a fuse before each unit. I leave both units disconnected from the battery unless they are in use. Also note that the voltage reading at the graphs WILL be different from the reading at the battery.

[haus9393]

I have charged batteries with graphs on dedicated power with no switch for like 5 years and never had an issue and I have the inline fuse. I'd bet your master switch was the issue. Glad you found it. Now you can sleep good at night