Common Causes of Battery Failure

The battery is not designed to last indefinitely; however, with proper care, it will provide many years of service. If the battery performs satisfactorily during testing but fails to operate properly for no apparent reason, the following are some of the more important factors that may be the cause of the problem:
1. Vehicle accessories left on overnight or for an extended period of time without the generator operating.
2. Slow average driving speeds for short time periods.
3. The vehicle's electrical load is greater than the generator output, particularly with the addition of aftermarket electrical accessories.
4. Conditions in the charging system such as electrical shorts, slipping drive belt, faulty generator or voltage regulator. Refer to Charging System for generator and charging system diagnosis. Charging System
5. Battery neglect and/or abuse, such as a loose battery retainer and hold down brackets or failure to maintain clean and tight battery connections.
6. Extended vehicle storage without proper battery protection. Refer to "Battery Protection During Vehicle Storage" for proper storage procedures.
7. New batteries received without proper charge.
8. Extended engine cranking due to poor engine mechanical conditions. Refer to Engine General Information and Mechanical Diagnosis and Engine Mechanical for engine diagnosis and repair procedures.
9. Incorrect interpretation of the built-in hydrometer. Refer to "Built-In Hydrometer" for proper hydrometer interpretation information.
10. Continued current draw on the battery through increased parasitic load.
11. Mechanical conditions in the electrical system, such as shorted or pinched wires.