1996 Ford F150 Owner's Manual - Page 74

Supplemental air bag readiness light Battery Voltage Gauge (Voltmeter) This gauge shows you the battery voltage when the ignition key is in the ON position. If you are running electrical accessories (when the engine is off, or idling at a low speed), the pointer may move toward the lower end of the normal band. If it stays outside the normal band area, have your vehicle's electrical system checked as soon as it is safely possible. If the battery is operating under cold weather conditions, the pointer may indicate in the upper range of the NORMAL band while the battery is charging. If you are running electrical accessories with the engine off or idling at a low speed, or the battery is not fully charged, the pointer may move toward the lower end of the NORMAL band. If it stays outside the NORMAL band, have your vehicle's electrical system checked as soon as it is safely possible. Battery voltage gauge 72