Batteries & Jump Starting

Batteries & Jump Starting answers from Piston Journal: troubleshooting fixes, step-by-step how-tos, comparisons and quick facts, each with the short answer first.

Batteries & Jump Starting

Is a Car Battery 12 Volts? What the Real Readings Mean

Is a car battery 12 volts? Yes, nominally, but a healthy one reads about 12.6 volts at rest and 13.7 to 14.7 with the engine running. What each reading means.

Batteries & Jump Starting

Why Is My Car Battery Smoking? Causes and Safe Fixes

Why is my car battery smoking? Usually overcharging from a bad alternator or the wrong charger. What to do right now, the likely causes, and when to call a pro.