Turn the ignition and let the engine idle.
: The alternator is faulty or slipping and not providing enough power. Auto xs battery and alternator tester instructions
: Alternator is undercharging or overcharging; the regulator or wiring may be faulty. : Alternator is faulty and not charging the battery. 4. Summary of LED Indicator Meanings Battery Test (Engine Off) Alternator Test (Engine On) Healthy / Full Charge Charging Correctly Low Charge / Needs Recharge Under/Overcharging Issues Faulty / Dead Battery Failed Alternator Safety Tips & Precautions Heat Warning Turn the ignition and let the engine idle
: Ensure the vehicle is parked on a flat surface with the engine turned off and the ignition key removed. Battery Access : Alternator is faulty and not charging the battery
To check the "resting" health of your battery, perform this test while the vehicle is parked and the engine is completely off.
Start the vehicle engine.