Charging the coach battery

[deltamaster]

I have a 2004 Four Winds Fun Mover Class "C" built on a Ford E-450 cutaway van chassis.

Recently I have noticed that it appears the coach battery is not charging when the chassis engine is running.

I have checked the circuit and found there is a cable from the engine battery that goes to a relay. Then the cable goes to the coach battery.

The relay activation circuit is energized in two ways. One is through the emergency start switch on the dash which energizes the relay. The other goes through a small electronic control and then to the ignition circuit for when the key is in the "on" position.

When the emergency start switch is depressed the power from the engine battery is sent to the coach battery and back so that power is shared between the two batteries.

When the ignition switch is turned on I can hear the relay click on but there is no power on the coach battery side of the relay. It is not until the engine is started that power is present on the coach battery side of the relay.

Problem is that with the engine running it seems there is still insufficient power sent to the coach battery. The lights are dimer unless the emergency start switch is depressed.

Does anyone here have any information on how this circuit operates and give me some information on what might be the problem.

The relay looks like the ones used in golf carts that are open when not energized but closed when they are energized to allow current through them. My experience with them is that they are either open or closed and either supply all power or none.

Are these systems different in some way?

[OnaQuest]

MEXICOWANDERER wrote:
I wouldn't tolerate a mickey-mouse setup like that for ten seconds. An automatic bi-directional charge relay is autonomous, and very durable. Check into the Sure Power bi-directional model.

Please inform us of how this is "mickey-mouse" as compared to the Sure Power.

The solenoid closes with the depression of the "Boost or AuxStart switch" just like the Sure Power.

The circuit board that the OP mentioned seems to be gating voltage to close the solenoid only when charging level voltage from the alternator is present. Just like the Sure Power.

There does appear to be some cable of contact resistance in the OP's setup somewhere, or his alternator is weak, but I see nothing wrong with the "mickey-mouse setup".

It doesn't seem to offer Bi-Directional activation, but that's pretty common in a Class-C.

Monaco, Winnebago and others used this setup for over 40 years before adding Bi-Directional charging in some of their largest rigs.

[rk911]

deltamaster wrote:
I have a 2004 Four Winds Fun Mover Class "C" built on a Ford E-450 cutaway van chassis.

Recently I have noticed that it appears the coach battery is not charging when the chassis engine is running.

I have checked the circuit and found there is a cable from the engine battery that goes to a relay. Then the cable goes to the coach battery.

The relay activation circuit is energized in two ways. One is through the emergency start switch on the dash which energizes the relay. The other goes through a small electronic control and then to the ignition circuit for when the key is in the "on" position.

When the emergency start switch is depressed the power from the engine battery is sent to the coach battery and back so that power is shared between the two batteries.

When the ignition switch is turned on I can hear the relay click on but there is no power on the coach battery side of the relay. It is not until the engine is started that power is present on the coach battery side of the relay.

Problem is that with the engine running it seems there is still insufficient power sent to the coach battery. The lights are dimer unless the emergency start switch is depressed.

Does anyone here have any information on how this circuit operates and give me some information on what might be the problem.

The relay looks like the ones used in golf carts that are open when not energized but closed when they are energized to allow current through them. My experience with them is that they are either open or closed and either supply all power or none.

Are these systems different in some way?

it's likely the charging diode on the alternator has gone to diode heaven.

[deltamaster]

Is this what you mean?
Sure Power: 12V 100A Battery Separator - Bi-Directional w/ Aux Start

[MEXICOWANDERER]

I wouldn't tolerate a mickey-mouse setup like that for ten seconds. An automatic bi-directional charge relay is autonomous, and very durable. Check into the Sure Power bi-directional model.

[MrWizard]

Sounds like the control for the relay has quit working
The manual override works, that means the relay and contacts are good
So the intuition on control sense had died our there is a loose or broken wire
If all the wiring appears solid, replace the system with some thing new