Forum Discussion
RoyB
Jul 05, 2016Explorer II
The easy way to tell is to use a mulitmeter across the trailer battery terminals with no shore power or generator connected. You will read 12.6-7VDC if the trailer battery is fully charged. Then with the truck 7-way connector plugged in and the truck motor running you should see the DC VOLTAHE across the trailer battery terminals jump up to around 14VDC. This will tell if the truck is charging your trailer battery.
On my trailer setup my truck with the iginition key has to be turned on and the truck motor running of course. MY 2010 F150 Truch has a relay and a fuse labeled tow charge or something to that effect that I found in the glove box in an unmarked plastic bag and had to install these two items in the Truck fuse panel to get mine to work. The truck manual identifed these two location as tow charger I think it was... The FUSE and RELAY allows the TRAILER TOW CHARGE to be controlled by the truck ignition key on my truck.
Roy Ken
On my trailer setup my truck with the iginition key has to be turned on and the truck motor running of course. MY 2010 F150 Truch has a relay and a fuse labeled tow charge or something to that effect that I found in the glove box in an unmarked plastic bag and had to install these two items in the Truck fuse panel to get mine to work. The truck manual identifed these two location as tow charger I think it was... The FUSE and RELAY allows the TRAILER TOW CHARGE to be controlled by the truck ignition key on my truck.
Roy Ken
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