Originally Posted by Diver007
Anyone know if you can jumper the House batteries to a dead chassis battery to start the engine ?
One-year-old house battery has Twice come up dead out of 50 times. Can't seem to find out what can draw down the battery with the key off and transfer switch off. Any ideas are welcome.
We can do it our 07 Raodtrek, but when I upgraded the electrical I made sure I used large enough components to do it safely.
You would need to get rid of the automatic battery separator that ties the front and rear together or jumper around it when needed, most likely need to upsize the cable to the rear along with the circuit breakers in that cable.
If you don't have the lithium or an engine generator you would probably have a #4 cable and 80 amp breakers in to the coach which isn't large enough for engine starting. We have very large cabling and battery capacity so no problem there, and use a manual charge relay to combine the front are rear batteries so very easy for use to do with a switch.
Don't just jumper around the existing separator without confirming the wiring can handle it. It is OK to charge the chassis battery from the coach on shore or solar power though, and the separator should do that for you automatically.