House battery not charging

[tobydad]

The house battery is not charging while engine is running. It charges when plugged in and when generator is running. Engine is charging at over 14 volts and the charging line leaving the engine battery to house battery is charging at over 14 volts, but the charge does not reach the house battery. There must be an in-line fuse somewhere and that is my problem. Does anyone know where it is. Motorhome is a 1998 E350 chassis with the V-10 engine. The fuse must be under the motorhome somewhere. I cannot find one under the hood and all automotive fuses were checked and are good.

[tboss]

there are two types of relays ,,one is a constant on and the other is for short burst like the starter relay.be sure you use the rite one..

[tboss]

there are two types of relays ,,one is a constant on and the other is for short burst like the starter relay.be sure you use the rite one..

[wwest]

Harvey51 wrote:
Our 2004 E350 uses the built in Ford auxiliary battery hanging system - a relay and fuse in the engine fuse box. From there, a cable goes under the vehicle to the trailer connector. Somewhere in between the cable has a branch with a connector pair supplying power to the house battery. We had a small problem with that connector; it had enough resistance to drop the charging voltage half a volt, which substantially affected the charging rate. Contact cleaner in the connector didn't solve it and I ended up soldering in a bypass around the connector for the positive wire.

That "connector" was likely an isolation diode (half a volt drop), you might want to return it to use.

[Harvey51]

Our 2004 E350 uses the built in Ford auxiliary battery hanging system - a relay and fuse in the engine fuse box. From there, a cable goes under the vehicle to the trailer connector. Somewhere in between the cable has a branch with a connector pair supplying power to the house battery. We had a small problem with that connector; it had enough resistance to drop the charging voltage half a volt, which substantially affected the charging rate. Contact cleaner in the connector didn't solve it and I ended up soldering in a bypass around the connector for the positive wire.

[tobydad]

Thanks for the replies everyone. There is no switch to boost the start battery. The motorhome is a 1998 Yellowstone Capri on a Ford E350 chassis with the V10 engine. It does not use a relay, but has a series of what I think are diodes located in the battery box where all the wires are connected and then goes to the house battery. I have checked with a multi-meter and the wire coming from below the motorhome does not read any voltage going to the "diodes". I have removed and cleaned all connections and when the rain stops and the ground dries, I will crawl under to see if I can follow the line.

[CloudDriver]

Dusty R wrote:
In our '03 Itasca, there is a relay that quite working in the middle of a long trip. I had to replace it in a parking lot next to an auto parts store.
If you tell us what make, model, and year your mh is maybe someone can tell you where yours located.
Dusty

The relay that Winnebago uses is in the picture below. The relay is operated by the ignition switch and connects the chassis and house batteries together when the ignition is on. Try turning the ignition switch on and off (without cranking the engine) and listen for a click or clunk sound, which will help in locating the relay (assuming you have one).

In the 10 years we have owned our MH I replaced the relay three times due to failure to charge the house batteries. The last time I bought this heavy duty relay, which I hope will last longer.

Winnebago's "Battery Mode Solenoid"

[GrumpyandGrandm]

wwest wrote:
If you have a switch wherein the house battery can BOOST the starting battery then there is NO fuse/CB in the circuit.

There is a fuse/cb in the isolator circuit. The emergency start button on the dash bypasses the isolator. Two totally different circuits.

[Dusty_R]

In our '03 Itasca, there is a relay that quite working in the middle of a long trip. I had to replace it in a parking lot next to an auto parts store.
If you tell us what make, model, and year your mh is maybe someone can tell you where yours located.

Dusty

[wwest]

If you have a switch wherein the house battery can BOOST the starting battery then there is NO fuse/CB in the circuit.

[pianotuna]

Hi

There is often a fuse or circuit breaker near the house battery. Trace the positive wire from the battery and see if you can find it.

[crasster]

Check all connections with a meter at the battery isolator.