GMC 2003 Envoy - Manual (Page 163)

Voltmeter Gage
When your engine is ngt
funning, bul The ignilion is
on (in RUM)j this gage
shows your battery’s slate
of Charge In DC voJls.
Whan the angino is running, the gage shows the
condition of (he charging system. Readings heiween (he
iaw and high wamir^g zones indicate ihe normal
operating range.
Readings fn The tow warning zone may occyjr when a
large number ot electrical accessories aro operating in
the vehicle and the engine is left Idling tor an
BKlendod porfod. This condition is normal since (he
charging systein is not able lo provide lull power
at on gin a idle. As engine speeds arg inengased, this
condilion should correct itselt as higher engine speeds
allow the charging syslom to create maKimum power.
Vou can only drive for a short lime with the reading
iis either warning zona. If you rnust drive, lam oft
all unnecessary accessories.
Readings in either warning гопа ir^dícate a possible
problem in the electrical system, Have the vehicle
serviced as soon as possible.
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