Engine won’t start or only clicks when you turn the key
Dashboard lights are very dim or don’t turn on
Headlights are weak or won’t turn on
Interior lights are dim or flicker
Power windows, radio, or other electronics work poorly or not at all
Battery warning light appears on the dashboard
Car starts after a jump but dies again soon after
Battery case looks swollen, cracked, or leaking
Corrosion is heavy on the battery terminals
Battery is older than 3 to 5 years
A multimeter shows about 12.6 volts when fully charged, and much lower readings can indicate a dead battery
The engine cranks very slowly or not at all
You hear repeated rapid clicking when trying to start the car