charging system problem

The way you tell is to read the DC VOLTAGE across the battery terminals using a multimeter...

When the SHORE POWER/GENERATOR is disconnected your batteries should read 12.6-7VDC if fully charged.

When you plug in to shore power/Generator your battery terminals DC VOLTAGE should jump up to the 13.6VDC telling you the batteries are being charged.

When you turn off shore power completely the battery terminals should drop back to the 12.6-7VDC showing they are fully charged. Then start your truck engine and the DC VOLTAGE on the battery terminal should go back up to the 13.6 VDC level depending what your truck alternator is putting out at that time...

You have already done this part with shore power/generator connected but you probably need to unplug the shore power/generator completely then start your truck and see if that switches to 13.6VDC coming from your truck alternator system.

Roy Ken

Already did the shore power disconect and started the truck no charge from truck, went for a 45 min. ride with heater on and the truck still would not charge batteries went down from 12.61 to 12.40

Dave

I have a cable that plugs into the 7 pin on the truck and the other end plugs into the camper. If yours is the same you need to check power coming out of the cable after it is plugged into the truck and also make sure the connector/plug on the camper side is not corroded.

I'dcheck all the fuses in the camper and dig into the wiring on the back side of the plug inside the camper, see if the problem lies there. Wouldn't be surprised if you lost a fuse.

going to go check now, camper charged in the fall without problems, brand new so I don't think the plugs are corroded, sealed it so no mice problem in the winter, but going to check the camper end of plug to make sure I am getteing charge to there, post back later with results

Dave

Checked all fuses all good multimeter would not read the end of the plug to tell if i was charging at the end of the cable so that might be the problem so i'll have to go to a camper place monday and get them to check it, or put a continuity tester on the cable tomorow see if I have flow through

Dave

There will be a fuse in the truck for the trailer charge circuit as well, you need to find that one and check it.

You stated......

I also checked the 7 way plug at the back of the truck it indicates power at the plug so that is not a problem.

So if you have 12V DC power at top right pin (1 o'clock position) then truck fuse(s) are good.

Camper umbilical cord may be wired to a fuse panel and you have a blown fuse on that 'charge' line (12V DC Power) before it connects to camper battery positive terminal
OR
TO a terminal Block and you have broken/loose wiring

As I understand the situation, when the truck is running there is proper voltage to the trailer/camper plug at the rear of the truck. Even so the connection may have sufficient corrosion to prevent the current from the truck to the camper. Best to clean anyways.

Next, where is the wire from the plug to the battery, trace it back, there may be a fuse, check the fuse. Then remove the wire supply at the battery and check for voltage from the trailer/camper plug, no voltage, double check the route, you may a broken or disconnect line.

Good luck.

rick

I had the same problem,I accidently shorted the 7 pin cable.It blew the 40 amp fuse in the truck.After I relaced that fuse,had no charging at the batts.Started searching and found a protection fuse between the 7 pin and the batts had blown'
Had to remove a drawer and the panel under the sink.