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caryt

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Seems the Alt has given up, voltage driving will drop to 12.2 to 12.5 then jump to 13+ but usually 12.5 or less. Normally was 13.7to 14v. Drove home yesterday 50 miles, check charging system came up once I got home. Checked battery and it was 12.3v. I have a Odyssey battery and the auxiliary was deleted. Its a '21 with 40k miles. Everything is tight etc. Options? I haven't found a aftermarket like a Powermaster available.
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LouisvEarlleJT

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Around 12.5 is what it's supposed to stay at on these. It is a "smart" alternator, so it's not always on (like on anything from the last 30 years). It's basically supposed to charge the battery up after start-up then only put out what's necessary to keep things at equilibrium (~12.5 volts). If it's always showing 13-14 then something is up with your battery
 
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caryt

caryt

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Ok but majority of coming home yesterday it showed 12.2v and when I got home the Battery tested 12.3v. Put it on a Battery Tender overnight and was 12.8v this am, now 4 hours later its 12.5v.
 
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VA6489

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I have something similar on my JTRD. Genesis aux battery like OP. Check the dash after start up shows 13.8-14.1 VDC. Also on start up I hear the Genesis switch kick in almost like it is needed to start the rig.

Batteries are 1 year old both from Genesis.
 
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If these have a battery management system it may need reset. It'll charge the battery less as it gets older.
 
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caryt

caryt

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The battery is 2 years old and yesterday going to town, 45 min trip volts stayed at 14.1 there and back.
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