Alternator wiring diagram?

DWISE557

MEMBER
1998 ISUZU TROOPER
6 CYL
4WD
AUTOMATIC
100,000 MILES

I have a trooper that wouldn't start I jumped it took it to the local parts store to check battery they told me it was the alternator so I change it. After about a week it wouldn't start again so I put a new battery in it again after about a week it wouldn't start again checked battery, battery good but now I'm not getting any thing at all when I turn on the key.
I'm get power to the fuse box( checked both side of main fuse have power) but not getting power to Ignition fuse? What can be wrong

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

Check for battery drain

Get a test light and disconnect the negative battery cable now put the light between the cable and battery negative post is the light On? If so start removing fuses one at a time -the fuse that turns off the light is the trouble circuit. Then break out the electrical wiring diagram below.

These guides can help

https://www.2carpros.com/articles/car-battery-dead-overnight

and

https://www.2carpros.com/articles/how-to-check-wiring

In the event you removed all the fuses and the light is still On disconnect the alternator batt. feed and the connector-if this one turns off the light-the alternator has bad diodes.

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