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Discussion Starter · #1 ·
This one is stumping me. This morning the 2004 started up just fine. Drove for an hour then stopped. About an hour later tried to start and just clicked. Was able to finally jump it and drove it home. When i got home,I left it idling and got my multi-meter. when probing the 2 batteries, virtually ZERO voltage with engine running. Inside gauge reads 14 volts. Turned engine OFF to check batteries. They read near ZERO. Now here is the rub. When I DISCONNECT the side terminals from batteries and check battery (part where terminals screw in) directly, the both read 12.67 (fully charged).

That is my issue. Hooked Up = no reading. Unhooked = full charge. Will take alternator to shop tomorrow for testing/rebuild, but battery reading perplex me.

Any thoughts?
 

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Sounds like the cables are corroded, or a bad ground. Remember the power is only as good as the ground. First clean the cables and check the ground. Also chech at the Red Jump Box- sometimes they are loose.
 

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This one is stumping me. This morning the 2004 started up just fine. Drove for an hour then stopped. About an hour later tried to start and just clicked. Was able to finally jump it and drove it home. When i got home,I left it idling and got my multi-meter. when probing the 2 batteries, virtually ZERO voltage with engine running. Inside gauge reads 14 volts. Turned engine OFF to check batteries. They read near ZERO. Now here is the rub. When I DISCONNECT the side terminals from batteries and check battery (part where terminals screw in) directly, the both read 12.67 (fully charged).

That is my issue. Hooked Up = no reading. Unhooked = full charge. Will take alternator to shop tomorrow for testing/rebuild, but battery reading perplex me.

Any thoughts?

where are you placing your meter leads when its connected. what your saying is not physically possible if you are metering the battery at the battery so the issue must be elsewhere. if you are metering from the battery to the frame, or from battery to battery then the issue could be a cable or a bad cell in one battery, but if you are testing post to post connected and disconnected there should not be a significant difference. if there is and you are SURE your meter and cables are not faulty, then disconnect the batteries immediately to prevent fire as the only other possibility is a dead short on the + wire and even that should not yield a 0 volt reading. .
 
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