Battery keeps dying.
Thread Starter
Teching In
Joined: Aug 2018
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Battery keeps dying. Just installed amp, long story short the battery keeps dying. The amp turns off with the radio so I know the antenna switch is wired properly. The alternator is charging the battery fine. My ground to the amp may not be that good so I’m gonna try to get a better ground but I’m not sure if that’s gonna make a difference or not. I’m gonna try installing a kill switch in the power wire and see if that helps. Any ideas what I should look for?
TECH Addict
Joined: Oct 2016
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From: PDX-OR-USA
Turn everything off, pull all the fuses, put a low current ammeter on the battery + , install each fuse 1 at a time, the one with over a few "ma" is your drain.
Weak alternator diodes are one of the heavy hitters on this one, as well as a dirty top on the battery..
Weak alternator diodes are one of the heavy hitters on this one, as well as a dirty top on the battery..
Thread Starter
Teching In
Joined: Aug 2018
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My alternator makes a crazy whining noise aswell. Guessing the alternator is going bad. How can I check the diode
TECH Fanatic
Joined: Dec 2017
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From: Bossier City, Louisiana
If you have a good quality multimeter, set it to AC volts and connect the meter to the battery with the engine running. If the alternator produces more than a tiny fraction of one volt (let's say around .02 VAC) of alternating current, one or more diodes in your rectifier is leaking AC. Replace the alternator. DC volts should be around 14.2 VDC.
The cheap and freebie multimeters from Harbor Freight generally are tough to read for small amounts of alternating current. These meters auto range their displays all over the decimal point making things tough to read. Let's hope you can find a good meter.
Rick
The cheap and freebie multimeters from Harbor Freight generally are tough to read for small amounts of alternating current. These meters auto range their displays all over the decimal point making things tough to read. Let's hope you can find a good meter.
Rick
