Alternator Voltage Readings: What's Normal?
Analyze Charging Health
Reference Ranges
- Battery resting: ~12.6V fully charged, 12.2V or lower indicates low state of charge.
- Charging voltage: Usually 13.5V to 14.8V warm.
- AC ripple: Below about 0.30V is typical on many vehicles.
- Cable drop: Keep positive and ground path drop below about 0.20V each under load.
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