Leisure battery grounding

Hi all,

Hopefully a straight forward question for you guys. I'm on the final phase of installing my leisure battery, so far I've:

- Ran a wire from battery to under passenger seat
- Installed renogy 60A dcdc charger (fused live from battery, negative to chassis)
- Ran a positive wire to under drivers seat ready for battery

My question is, do I need to run a negative from leisure battery to the dcdc charger, or do I ground the leisure battery to the chassis, or both?

Also who knew the handbrake was secured to the drivers seat base? Don't do this on a slope, almost destroyed my garage door 😂

T6.1
 
If you’ve grounded the charger to the chassis then just do the same for the leisure battery.
 
Hi all,

Hopefully a straight forward question for you guys. I'm on the final phase of installing my leisure battery, so far I've:

- Ran a wire from battery to under passenger seat
- Installed renogy 60A dcdc charger (fused live from battery, negative to chassis)
- Ran a positive wire to under drivers seat ready for battery

My question is, do I need to run a negative from leisure battery to the dcdc charger, or do I ground the leisure battery to the chassis, or both?

Also who knew the handbrake was secured to the drivers seat base? Don't do this on a slope, almost destroyed my garage door 😂

T6.1
Lucky with the door. As Deaky says just go to the floor bolts. I couldn't as i had to remove the one under the passenger seat to sit my battery down a bit further so used seatbase bolts but cleaned off any paint to ensure as good contact. Also ended up putting a busbar in as I run an inverter too and wanted to be sure
 
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Thanks for all the replies, I will give it a go tomorrow! Also, I know there’s so many threads on this but what colour wire would an ignition live be? I have a suspicion that I may have one under the seat since I have an own battery feed there
 
Ok, so this is what I have under passengers seat, from memory the fuse is for the 12v sockets, but I haven't a clue what the relay is for.

The power to the fuse is only 12v when ignition is on but I'm wondering is the relay is only triggered when the engine is running.

My thoughts for triggering the charger are:

1) piggy back of the fuse, but this would drain the battery if left on accessory for a while

2) maybe the relay has the elusive ignition live on it which would be the better option

Am I at least in the right ball park, anyone know what this relay does?

Thanks

IMG_20250505_140352137_HDR.webp
 
Ok, so I measured the pins on the relay, taking the brown as earth the other pins read 13v with engine off and 14.5v with engine running on one pin, 4.5v regardless ok another and nothing iron the other pins. When the engines off there is no voltage and whatever I do I couldn't get the relay to click. Also didn't affect anything if I removed it.

I'm at a loss to what this is!
 
Even for high currents, for example a 3000W inverter?
I installed a busbar straight from the LB in 25mm cable for my inverter. On the plus side i also connected my Orion etc to this so direct to LB as well as chassis earth.1000007630.webp
 
I installed a busbar straight from the LB in 25mm cable for my inverter. On the plus side i also connected my Orion etc to this so direct to LB as well as chassis earth.View attachment 285708
Thanks, that doesn't answer the question if the OEM under seat earth point would take currents upwards of 300A. 25mm2 cable also might be a bit on the skinny side for those currents.
 
I only have a 1500w inverter so should be ok. I was advised to run a negative from the LB to the inverter hence the busbar in the photo
 
Ok, so I measured the pins on the relay, taking the brown as earth the other pins read 13v with engine off and 14.5v with engine running on one pin, 4.5v regardless ok another and nothing iron the other pins. When the engines off there is no voltage and whatever I do I couldn't get the relay to click. Also didn't affect anything if I removed it.

I'm at a loss to what this is
Just gonna bump this as I could really do with some help on this
 
Ok, so I measured the pins on the relay, taking the brown as earth the other pins read 13v with engine off and 14.5v with engine running on one pin, 4.5v regardless ok another and nothing iron the other pins. When the engines off there is no voltage and whatever I do I couldn't get the relay to click. Also didn't affect anything if I removed it.

I'm at a loss to what this is!
I think it is the original split charge relay, which you don’t need now.
 
I think it is the original split charge relay, which you don’t need now.
Thanks, I'm kind of thinking along the same lines, but have read it may need activating in vcds?

Either way, I'm just after something to trigger my dcdc without the need to run another cable
 
The relay should have feed from the starter battery, output to the leisure battery, a run signal and an earth. The first two should be in thicker gauge wire. You should be able to use the run signal wire for your DC DC charger
 
Thanks, I'm kind of thinking along the same lines, but have read it may need activating in vcds?

Either way, I'm just after something to trigger my dcdc without the need to run another cable
I don’t think 645 is the split charge relay - see what you can find using the search function , or if a member look at the schematics
 
Even for high currents, for example a 3000W inverter?
The seat bolts are just a double threaded stud so whilst you might clean the paint from around the seat base you don’t know how clean the connection is at the other side of the stud.

I think I’d be connecting a 3000w inverter straight to the battery or shunt terminals
 
Thanks, I've spent hours sifting through different posts and am none the wiser unfortunately.

I've run some tests with the multi meter and nothing seems to change it, in fact nothing seems to change/not work even when I remove the relay
 
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