aternator to battery problem
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aternator to battery problem
new battery and new alternator but battery is not getting charged at all.. what do i do, no blown fuses connections to each are clean and solid.. is it a bad ground somewhere? help...
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Joined: May 2003
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From: Kalispell, Mt.
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From: Virginia
I don't know what year truck you are working on, but most have a fusible link in the output wire of the alternator. Follow the large output wire up from the alt, and somewhere in the harness, there should be a fusible link if you have an older truck, or it may have a fuse in the fuse box if it's a newer truck.
If you want to be sure if it's charging or not, measure the voltage of the battery with the engine not running, and then when it's running. It should be higher with the engine running.
If you want to be sure if it's charging or not, measure the voltage of the battery with the engine not running, and then when it's running. It should be higher with the engine running.
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As Franklin2 said, there is a fuseable link in the system. It is a special piece of wire spliced into the wiring harness at a connection. It would be on the starter solenoid or starter where the battery lead connects. It may not appear to be melted or burned or the insulation could look scorched. Do the voltage test he suggested. If you do not see increased voltage at the battery when the engine is running on fast idle the alt is not charging the battery. The next place to check is the alternator output. With the engine off if you have no voltage at the alternator on the output terminal that fuse link, or the wiring is bad. If there is voltage there but the alt does not charge it is an alternator/regulator problem. It is unlikely that the problem is bad grounds but not impossible. A bad ground would probably still charge, just not too well.
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From: nova scotia, canada
alt
is the new alt the exact same as the old one. are all the wires connected back up in the same way they came off. does this alt have an external regulator? is there a good ground to the block (if it started whit the new bat then the block ground is ok). you could have a wiring problem at the excite wire. if it doesn't get a signal to charge then it won't. depends on the alt. from the output terminal of the alt test the voltage to the neg of the bat if its over 13.2 volts at idle then the problem is the red wire to the batt. does the dash light come on to tell you its not charging when the truck is running?
