Electrical Battery charge from car

KevD

New Member
May 11, 2022
7
3
3
Highett, Vic
Hi again. New to me 2015 17.56. The battery in the van charges from the car. But requires both Anderson and 12 pin to be plugged in. Is this normal?
 

Drover

Well-Known Member
Nov 7, 2013
11,859
18,384
113
QLD
www.expandasdownunder.com
No ................ usually the anderson does the fridge while the 12pin is left to do the 12v supply to van, could be an earthing problem or just weird set up, best way is to track each connection and see whats what, multi meter is handy... A simple test is to plug 12pin in, engine running, turn off battery switch in van, van lights should operate if 12pin supplying power which in turn should mean that when battery turned on it will be getting charged via the Setek......
Try to follow the Anderson cable to see where it goes, otherwise a check would be to again plug into tug, engine running, van battery off, confirm power at anderson then again at rear of fridge where the 12v terminal block is, of course if a fridge switch fitted this won't work. and do the same test with the lights.. the lights should come on with any one of the following 240v, battery switch turned on or connected to Tug and plugged in......
 
  • Like
Reactions: Boots in Action

CarlDry

New Member
Jan 5, 2019
23
12
3
Bundaberg
Anderson is generally connected to fridge only. The 12 pin is not used to charge the battery in the van, it is only used to let the fridge know when the tow vehicle ignition is on (generally so slides can not be moved while the van is being towed and to prevent the fridge from automatically switching to gas and igniting as soon as the ignition is turned off. This way the fridge doesn't ignite next to a fuel bowser when your filling up.) If you want to charge the battery you will need to run another cable from the tow vehicle and fit a dc-dc charger (JHUBS are not a DC-DC charger). If you run a new cable it should be a minimum of 6B&S all the way from the car battery (4B&S would be better).
 

Drover

Well-Known Member
Nov 7, 2013
11,859
18,384
113
QLD
www.expandasdownunder.com
Anderson is generally connected to fridge only. The 12 pin is not used to charge the battery in the van, it is only used to let the fridge know when the tow vehicle ignition is on (generally so slides can not be moved while the van is being towed and to prevent the fridge from automatically switching to gas and igniting as soon as the ignition is turned off. This way the fridge doesn't ignite next to a fuel bowser when your filling up.) If you want to charge the battery you will need to run another cable from the tow vehicle and fit a dc-dc charger (JHUBS are not a DC-DC charger). If you run a new cable it should be a minimum of 6B&S all the way from the car battery (4B&S would be better).


I beg to differ the BMPro series of RV management systems does take 12v from the tug via 12 pin or anderson, (personal preference) and doesn't require a seperate DC-DC charger in tug or van, it will charge the batteries via solar, 240v mains or 12v, the 12v supply runs to the Aux on the BMPro systems

On an auto fridge the D+ wire should be connected to a tug ignition supply of 12v to enable the fridge to see the tug is plugged in and in theory shut down when key is off, usually though its connected to the same fridge feed line, with the fridge disconnected by unplugging or a fridge switch relay operating a shut down the fridge will attempt to connect to LPG therefore a fail safe of 10 mins delay is fitted so that gas won't start in case the operator had a brain fart and didn't shut off gas at hook up, with an analogue fridge its not a problem as it require input to operate........

Of course if you have ample solar 12v charging from tug is redundant and a waste of money...
 
Last edited: