Part and system guide

Battery

The battery stores electrical energy for starting and stabilizes voltage for the vehicle's electronics.

What it does

Provides high current to the starter and powers modules before the engine is running.

Failure signs

Slow cranking
Rapid clicking
Dim lights
No start after sitting
Corroded terminals

Maintenance notes

Keep terminals clean and tight.
Test battery health before winter or extreme heat.
Check charging voltage after replacing a repeatedly dead battery.