When the engine is running, the battery voltage should be within which range?

When the engine is running, the battery voltage should be within which range?

• A. 13-15 volts
• B. 11-12 volts
• C. 9-11 volts
• D. 16-18 volts

Answer: (A)

When the engine is running, the alternator charges the battery and powers the electrical system, so you should see a higher-than-resting voltage at the battery that stays within a safe charging range. A typical, healthy reading is about 13.5 to 14.5 volts, commonly described as roughly 13–15 volts. This tells you the charging system is supplying current to both the battery and the vehicle’s electrical loads. If the reading drops to about 11–12 volts with the engine running, the alternator isn’t charging properly or the belt/tul loid is slipping, and the battery may discharge despite the engine running. A range of 9–11 volts is too low and indicates a charging problem or a heavy load pulling the voltage down. On the other hand, a reading of 16–18 volts suggests overcharging, which can damage the battery and electrical components and usually points to a faulty voltage regulator or alternator. To check, measure across the battery terminals with the engine running; you should see roughly 13.5–14.5 volts.

When the engine is running, the alternator charges the battery and powers the electrical system, so you should see a higher-than-resting voltage at the battery that stays within a safe charging range. A typical, healthy reading is about 13.5 to 14.5 volts, commonly described as roughly 13–15 volts. This tells you the charging system is supplying current to both the battery and the vehicle’s electrical loads.

If the reading drops to about 11–12 volts with the engine running, the alternator isn’t charging properly or the belt/tul loid is slipping, and the battery may discharge despite the engine running. A range of 9–11 volts is too low and indicates a charging problem or a heavy load pulling the voltage down. On the other hand, a reading of 16–18 volts suggests overcharging, which can damage the battery and electrical components and usually points to a faulty voltage regulator or alternator.

To check, measure across the battery terminals with the engine running; you should see roughly 13.5–14.5 volts.