Joined the club, killed my house batteries

[Cutwater28GG]

The research I did has the solix at the lowest idle draw compared with the competition

 

[brtnstrns]

You need to jump-start them. The BMS protected them. Easiest way to do that is to start the engine, so it's running. Parallel your engine and house, as that'll provide 14+ volts to the (6) Dakota batteries you have. That will jump-start them to start taking a charge. Then turn on your battery charger, un-parallel the engine and house (don't leave them in parallel for very long). Turn the engine off. Your battery charger should be able to finish charging your house lithium bank to fully charged. With a 60 amp battery charger and 600 ah, it'll take awhile... figure at least 12 hours.

Coincidentally, I also completely depleted my Dakota LFPs on our R-25 this week, so I tried this method just now.

I didn't seem to get any indication that it actually worked. Even with the engine running, turning the switch to parallel, there were no signs of the house system getting any voltage at all.

It may be a completely false memory, but I do feel like during orientation they said the parallel switch is between the engine and thruster battery. I may be incorrect there, but if not, there may not be a good way to parallel the engine to house LFP batteries.

 

[Submariner]

It may be a completely false memory, but I do feel like during orientation they said the parallel switch is between the engine and thruster battery. I may be incorrect there, but if not, there may not be a good way to parallel the engine to house LFP batteries.

The newest boats (mid-year 2026 and newer) come with EPOCH batteries which don't support engine starting. They have their parallel switch wired to connect the thruster battery to the engine battery. The Dakota's were wired such that you could parallel the house and engine.

With EPOCH batteries, you need jumper cables.

 

[brtnstrns]

The newest boats (mid-year 2026 and newer) come with EPOCH batteries which don't support engine starting. They have their parallel switch wired to connect the thruster to the engine. The Dakota's were wired such that you could parallel the house and engine.

With EPOCH batteries, you need jumper cables.

Interesting. Ours is a 2025, probably one of the last, if not the last before the switchover to electric steering and all that jazz.

Would you expect that with the engine running, parallel switch on there would be any signs of life? Lights wouldn’t turn on nor would the victron monitor when I tried earlier today following the process you laid out in your previous comment.

Going to go back down this evening to troubleshoot with actual tools on hand. It was just a coincidence I went down there earlier to find it dead and noticed this thread was ongoing.

 

[Submariner]

Interesting. Ours is a 2025, probably one of the last, if not the last before the switchover to electric steering and all that jazz.

Would you expect that with the engine running, parallel switch on there would be any signs of life? Lights wouldn’t turn on nor would the victron monitor when I tried earlier today following the process you laid out in your previous comment.

Going to go back down this evening to troubleshoot with actual tools on hand. It was just a coincidence I went down there earlier to find it dead and noticed this thread was ongoing.

Do you have EPOCH's or Dakota LFP batteries?

 

[brtnstrns]

Do you have EPOCH's or Dakota LFP batteries?

Dakota

 

[boatliker]

You need to jump-start them. The BMS protected them. Easiest way to do that is to start the engine, so it's running. Parallel your engine and house, as that'll provide 14+ volts to the (6) Dakota batteries you have. That will jump-start them to start taking a charge. Then turn on your battery charger, un-parallel the engine and house (don't leave them in parallel for very long). Turn the engine off. Your battery charger should be able to finish charging your house lithium bank to fully charged. With a 60 amp battery charger and 600 ah, it'll take awhile... figure at least 12 hours.

This worked like a charm. Back up to 100% in about 9 hours, maybe less. Thanks for the assist, Martin.

 

[brtnstrns]

Do you have EPOCH's or Dakota LFP batteries?

This worked like a charm. Back up to 100% in about 9 hours, maybe less. Thanks for the assist, Martin.

Went down to the boat last night and threw my multimeter on the Dakota house batteries: 0.31 VDC. Checked continuity between house and engine batteries with parallel switch both on and off and couldn't get continuity anywhere. Thinking my parallel switch isn't doing anything at all so I'll need to bug the folks at Fluid Motion about that since that could lead to some big issues if I wasn't at a marina.

Finally was able to wake the batteries up with a victron battery charger (only own EVs now so don't carry jumper cables with me anymore) and got them up enough to let the boat's charger take over.

 

[Submariner]

Went down to the boat last night and threw my multimeter on the Dakota house batteries: 0.31 VDC. Checked continuity between house and engine batteries with parallel switch both on and off and couldn't get continuity anywhere. Thinking my parallel switch isn't doing anything at all so I'll need to bug the folks at Fluid Motion about that since that could lead to some big issues if I wasn't at a marina.

Finally was able to wake the batteries up with a victron battery charger (only own EVs now so don't carry jumper cables with me anymore) and got them up enough to let the boat's charger take over.

I'd pull the panel on the DC switches for engine, house, parallel, thruster. Take voltage readings from behind those DC switches to figure out what gets joined when you turn on the parallel switch.