Coach Battery not charging While driving - 2006 Thor Four Winds class c

[KandT]

Will do ten bear - seems like a good thing to have in the tool box!!!

[KandT]

A very sincere and enthusiastic thank you to all that weighed in and educated me on this problem!!

I fixed it this morning and couldn't be more excited!!

I wouldn't have been able to figure it out without the forum help!

By the way I looked and looked and can't find an aux start switch. Anyone with the same coach know if I have one?

[KNMIB]

Originally Posted by KandT

A very sincere and enthusiastic thank you to all that weighed in and educated me on this problem!!

I fixed it this morning and couldn't be more excited!!

I wouldn't have been able to figure it out without the forum help!

By the way I looked and looked and can't find an aux start switch. Anyone with the same coach know if I have one?

I have a 2012 Four Wind and the emergency start switch is to the left of the steering column.

[KandT]

Originally Posted by KNMIB

I have a 2012 Four Wind and the emergency start switch is to the left of the steering column.

Thanks!! I wish it was there on mine!

[tenbear]

AFAIK, I don't have one in my 05.

Maybe it is not required since turning the ignition on puts the chassis battery and coach battery in parallel. Of course, the coach battery is connected with relatively small wire.

[KandT]

Ahhhh Ten Bear you answered my thought without me having to ask It.

So what happens if the coach battery is drained or dead? Will chassis batt still start the engine?? Also, could it send more energy to house batt instead of chassis as it charges?? Mine seemed to be sending 14.1 volts to chassis and 13.9 to house but my house was fully charged

[tenbear]

Originally Posted by KandT

Ahhhh Ten Bear you answered my thought without me having to ask It.

So what happens if the coach battery is drained or dead? Will chassis batt still start the engine?? Also, could it send more energy to house batt instead of chassis as it charges?? Mine seemed to be sending 14.1 volts to chassis and 13.9 to house but my house was fully charged

Well, If you are measuring the voltages at the batteries, the difference is due to the voltage drop in the wires. The engine is wired with heavy wires and the length of the wires to the chassis battery is much shorter than the wire to the coach battery.

If you are measuring the voltages on the two connections on the solenoid, the voltages should be pretty much the same. If not, the solenoid has a voltage drop that I wouldn't expect.

Would the chassis battery start the engine if the coach battery was drained? I suspect so. The wire is long and with the voltage drop in the wire, the coach battery will probably not accept much current.

Will the coach battery start the engine if the chassis battery is drained? I doubt it. Too much and too small wire.

[tenbear]

Another thought after re-reading your post.

The alternator sends the same voltage to the batteries and the voltage that the batteries receive is reduced by the voltage drop in the wires.

The energy that the batteries receive depends on their state of charge. Batteries only draw the current that their state of charge allows. A fully charged battery will draw only a little current while a fully drained battery will draw quite a lot of current. Think of energy as voltage times current (power).

If you are interested in learning more, google "The 12 volt side of life". It has lots of info.

[KandT]

Originally Posted by tenbear

Another thought after re-reading your post.

The alternator sends the same voltage to the batteries and the voltage that the batteries receive is reduced by the voltage drop in the wires.

The energy that the batteries receive depends on their state of charge. Batteries only draw the current that their state of charge allows. A fully charged battery will draw only a little current while a fully drained battery will draw quite a lot of current. Think of energy as voltage times current (power).

If you are interested in learning more, google "The 12 volt side of life". It has lots of info.

So Ten Bear it sounds like your system works exactly the same as mine does. Over the years I would guess you have had a less than fully charged house battery? Did your chassis start right up?

Also, I did start to read "the 12 volt side and of life". Good info!

[tenbear]

I have never had a problem starting the engine. I am careful to keep the coach battery above 12.1v. I don't recall ever having the coach even near fully discharged. I have replaced the coach battery so it probably did get discharged at some point, I don't remember.

[KandT]

Sounds good Ten Bear. I will move that into my "Don't worry about that" pile and make room for a new worry😀