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Dead Parrot · 06-23-2020, 10:01 AM

Yes. Normal behavior. My CUCV has dual 12V alts in a weird 24V setup. Two idiot lights. If on start the 6.2 diesel doesn't rev enough, one or both Gen lights stay on and the voltmeter stays in the yellow (no charging) zone. Bump the throttle and the light(s) go out and the voltmeter quickly climbs into the green zone.

Having working idiot lights or matching resistors are important. Without the small excite current, the alt won't start generating. That was why I suggested doing the remove/replace on the two wire plug. Replacing a heater core has plenty of chance to bump or jerk on those wires and plug.

06-23-2020, 10:01 AM	#5
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,663	Re: Heater core change. Now no charge Yes. Normal behavior. My CUCV has dual 12V alts in a weird 24V setup. Two idiot lights. If on start the 6.2 diesel doesn't rev enough, one or both Gen lights stay on and the voltmeter stays in the yellow (no charging) zone. Bump the throttle and the light(s) go out and the voltmeter quickly climbs into the green zone. Having working idiot lights or matching resistors are important. Without the small excite current, the alt won't start generating. That was why I suggested doing the remove/replace on the two wire plug. Replacing a heater core has plenty of chance to bump or jerk on those wires and plug.