Issue with gauges coming on after dual battery install

[Tobes]

So I used the Blue Seas dual battery switch with ACR. Have it all hooked up turn on the power. Accessories all come on, boat starts up, but the gauges do not come on. Tach wont work.

Now, I have an OFF/ON/COMBINE option. If I set it to ON, all the accessories work and engine will start but no gauges (RPM/speedo/digital readout). If I put it on combine batteries, it works just fine (all accessories, engine starts, gauges good).

Now, before I started, I fired up the boat just to ensure everything was working properly in case of an issue like this. Everything worked including gauges.

Any ideas? Thanks in advance. Only thing I can think is possible not enough juice in the battery? Maybe its low? Typically, I have been running the boat weekly but it has sat for 3-4 weeks now. My charger is due here tomorrow and it will be installed promptly (should have picked it up sooner).

Only thing I can think of is one of the batteries is low (not sure if the gauges run on accessory power or engine circuit??) and not enough juice unless both are on? Even when the engine is running it wont come on without combine battery setting.


** No need to bump this but figured out the issue. The *new* battery I purchased apparently wasnt charged. Maybe it sat around for a bit, not sure. Unfortunately, when I went to hook up the charger (permanent install), the post spun while removing the nut that holds the cables on. I had to cut it off ;/ Doubt they will warranty the battery although I hope so if I end up having issues with it. As of now, the battery is fully charged and there is no issue with the gauges not coming on.

Pretty weird that the motor would start, stereo would run at full power, blower/lighting would come on, but the gauges would not work. Either way, all good now. On to cutting a hole in the side of the boat for that convenient charging port.

 

[veedubtek]

That is a little odd. Glad you got her sorted though!

 

[Julian]

I assume you connected the boats house line to the 2nd battery and the 2 starter cables to the starting battery, and that it was the new house battery that was dead? The helm all runs off that house line.

 

[Tobes]

Yes, it was the house battery that was brand new. Just not charged. Maybe it sat around for a bit. Once I got the charger on it for a good 24 hours (NOCO Mini 8amp charger, 4amp each bank) it was good to go. It was just weird because the stereo would play full volume but the gauges wouldnt work even with the stereo off. Electrical gremlins right?

All good now though. Thanks for the reply. Got everything hooked up and operating properly. Got my marinco outlet installed as well (went with it because I was able to wire the plug instead of actually plug into the back like some of them).

 

[Tobes]

So, after a few more outings and what not, I discovered that the issue was not fixed. I was getting the same thing. I figured that a cell was dead in the new battery so I used it as an excuse to upgrade to AGM. Picked up a starting and deep cycle. Installed batteries, tested it all out in the garage (started boat, ran it for oil change, ect) and all was good. Gauges would immediately come on each time.

Went to the lake today (keep in mind batteries were on charger, charger showing green when I pulled the plug meaning they were on maintain mode) and when I got there, same shit happened. Gauges would not come on. I could use the radio, bilge, blower, accessories but the gauges would not work unless I went to combine mode. This just not make any sense at this point. Pretty frustrating at this point. Voltage is fine when this happens as well. Any ideas at all? About to go back to a single battery setup........ Would it hurt anything to always run combine mode?

 

[Bruce]

Is there a jumper between the negatives on the two batteries?

Where do the gauges get power? Is it from the accessory circuit or the engine circuit? I suspect it is from the engine circuit.

 

[Tobes]

Is there a jumper between the negatives on the two batteries?

Where do the gauges get power? Is it from the accessory circuit or the engine circuit? I suspect it is from the engine circuit.

Thanks for the reply. No jumper between the negatives. Maybe I should try this?

Helm gauges run off the house line (as Julian stated above). Its just the factory helm gauges, no aftermarket stuff. I guess where I am at with it is why can I use the radio, bilge, blower (radio maxes at 160w RMS that I have installed) but the gauges wont come on? As soon as I turn the batteries to combine, gauges come on. I guess after typing everything and having it intermittent, seems like a possible grounding issue somewhere as you seem to have suggested.

 

[Bill D]

Yeah, you need to have the negatives of the two batteries tied together.

 

[Tobes]

Yup, thanks for the replies.

For some reason, I did not realize they needed to be tied together but after thinking about it, it makes sense. Just threw on a negative post to negative post cable and all is well (I believe). Tried it just before installing it and the gauges would not turn on. Installed it and gauges are working again. Glad I do not have to worry about it anymore!

Now for fish finder install this week!

 

[Bruce]

Thanks for the reply. No jumper between the negatives. Maybe I should try this?

I bet adding one solves your problem. You can not run positive from one battery and negative from the other. There needs to be a common negative bus.

 

[Julian]

Installed it and gauges are working again.

Glad you were able to get to the bottom of the problem! Mod on!