charging issue
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charging issue
I have a 1997 expedition Eddie Bauer 5.4. A week ago I got the gremlins due to, I've since found out, the windshield leaking problem. I replaced the inside fuse box/gem with one out of a junk yard. It started and ran fine. Drove it around for a little while that same day when it died due to running out of battery life. Long story short I've now replaced the battery, two alternators, starter, alternator mega fuse, alternator plug, main cable from the mega fuse to alternator, neg battery cable, checked all relays and fuses and still shows the same signs. Before start the batt shows 12.30 volts. After start it shows anywhere from 11.8 to 12.00 volts. Everything shows its getting power but I've always been told after starting it should read between 13.3 to 14.4 volts. Any help would be deeply appreciated. I just bought this truck and am already very disappointed.
Postmaster
Joined: Sep 2010
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From: Southern Cal
Yep, you are not getting any charge. Battery voltage s/be about 12.8 volts static., 13.8-14.2 running at the alternator terminal, slightly less at the battery.
Sounds like it started with the gem box change. Are you sure the long one is compatible and that all connections are correct? Are all three wires connected properly on the back of the alternator?
To Jim's point, I would expect to see your alternator light to illuminate here if connections are correct.
Sounds like it started with the gem box change. Are you sure the long one is compatible and that all connections are correct? Are all three wires connected properly on the back of the alternator?
To Jim's point, I would expect to see your alternator light to illuminate here if connections are correct.
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Long story short I've now replaced the battery, two alternators, starter, alternator mega fuse, alternator plug, main cable from the mega fuse to alternator, neg battery cable, checked all relays and fuses and still shows the same signs. Before start the batt shows 12.30 volts. After start it shows anywhere from 11.8 to 12.00 volts.
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Fleet Owner
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In that case the problem is with the two alternators you installed, or there is no ground bond between the engine block and the body, or the belt is slipping.
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Alternators can test good when cool and fail when hot. When you took the voltage reading with the engine running, was the alternator hot or cool?
Logistics Pro
Joined: Jan 2001
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From: Central NYS
+1
But don't measure continuity.
With the engine running and with lights and heater fan on high, measure the voltage drop between the alternator frame and the battery negative post with your DMM. You want to see less than 0.2 volts dropped on the ground side.