Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 10, 2025 ...

Re: Battery advice

Reply #25 – March 10, 2019, 05:48:55 pm

Check again at both dash voltmeter and monitor with engine at 1100 RPM.  Let us know what you find.

And, even if voltage was 12.5, there are other things than the alternator that can cause this.  Let us know what you find and we can walk you through troubleshooting (assuming you have a digital voltmeter).  NOT difficult.

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Re: Battery advice

Reply #26 – March 10, 2019, 07:05:42 pm

Dash gauge looked like 12.8 on the needle and the audit monitor was 14.3v at 1100rpm.  Turned over and started quick.  Are they measuring 2 different things?

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Re: Battery advice

Reply #27 – March 10, 2019, 07:10:23 pm

Dash voltmeter is notoriously inaccurate.  But, easy to check:

Locate the battery isolator-- on most, raise the bed and it will be on the front wall of the engine room.

With engine on and around 1100 RPM, check voltage between good ground and:

Center terminal (from Alternator B+/alternator  output)
The two outer terminals-- one to each battery bank.

Let us know what you find.

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Re: Battery advice

Reply #28 – March 10, 2019, 07:29:56 pm

Facing rear bed open. Center 14.8 left13.93 right 14.03

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Re: Battery advice

Reply #29 – March 10, 2019, 07:37:19 pm

Those readings are fine.

Now, check voltage at the two battery banks.

Find out how you went from 13.93 or 14.03 at the isolator (connected by large-gauge cables to the batteries) down to 12.5 that he read at the battery!

Could be nothing more than a corroded or loose connection.

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