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Voltage goes down when idle. Battery, alternator, and starter check out. ?

(2003 Chevrolet Suburban 1500)
in Dayton, OH on November 10, 2013
My truck stalled while turning and the voltage is going down when the truck is in idle. Had the battery, alternator, and starter check out fine. What else could be wrong?
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Popular Answer
of G. T. Service Center on November 10, 2013
When turning your engine dies, you have to restart it? Amp gauge drops as it was tested? Test showed good at the same time?
of Gillespie's Auto Service on November 10, 2013
Depending on how many accessories are running, it can be considered normal for the system voltage to drop when you come down to idle and the battery is required to full fill one of its jobs and that is to supplement the charging system. So the questions go, "How low does the system voltage go"? Is there any other symptoms that need to be considered? GM will command the alternator to turn off if the computer senses that the engine is about to stall, that removes that extra load and can help prevent stalling. You may need an experienced tech to check this carefully.
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