Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 12, 2025 ...

Charging issue

January 06, 2024, 09:08:03 pm

When I start the coach, voltage on dash gauge goes to about 13.4 volts.  After an indeterminate amount of time, the voltage will go down under 12 volts immediately and the voltage back on the invertor panel will go up to 16 to 17 volts.  I can flip the boost switch and the voltage levels off at 13.4 at the gauge and 14 at the invertor panel.  I can switch the boost back off and voltage holds as it should........ any ideas?..... thanks

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Re: Charging issue

Reply #1 – January 06, 2024, 09:12:47 pm

Start by checking your batteries one at a time one cell could be bad.

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Re: Charging issue

Reply #2 – January 06, 2024, 09:17:05 pm

Batteries seem to be good...... all this is occurring with the engine running.

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Re: Charging issue

Reply #3 – January 07, 2024, 12:04:06 pm

Hi Lynn & Marilyn,

Good to see your names. We miss your annual seasonal gifts.

Not sure about your voltage issue, but it seems that 16 or 17 volts can only come from the alternator. And boost solenoid only connects both battery banks together.

Could be that the alternator voltage sense wire has a bad connection to the engine battery bank. OEM this alternator voltage sense connection was poorly designed in that it was picking up start battery voltage reading at isolator panel, where any number of problems could cause a bad reading.

The best correction to the alternator voltage sense is to run a separate wire from alternator to an in-line fused connection at the start battery positive post. Easy to determine which small alternator wire is voltage sense. Using a small PVC pipe between the frame members to route the new sense wire from street side to curb side works very well.

Long before problems show up, this mod is always a good preventative improvement to eliminate future problems. All should consider making this improvement.

Barry & Cindy

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Re: Charging issue

Reply #4 – January 07, 2024, 01:25:13 pm

Thanks...... I will make an attempt to check and correct that.

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