Operation CHARM: Car repair manuals for everyone.

Battery Common Causes of Failure

The battery is not designed to last indefinitely, but will provide many years of service with proper care. If the battery performs satisfactorily during testing but fails to operate properly for no apparent reason, the following factors may be the cause of the problem:
1. The vehicle accessories have been left on overnight or for an extended period of time without the generator operating.
2. The battery may not have sufficient time to recharge if the vehicle has been driven at low average 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. One of the following faulty conditions exist in the charging system:
^ Electrical shorts
^ A slipping drive belt
^ A faulty generator
^ A faulty voltage regulator

Refer to Charging System Check. Component Tests and General Diagnostics
5. The battery has been neglected and/or abused.
This is indicated by the following conditions:
^ A loose battery retainer
^ Loose hold down brackets
^ Dirty battery connections
^ Loose battery connections
6. The vehicle has been stored for an extended period of time without proper battery protection.

Refer to Battery Electrical Drain/Parasitic Load. Battery Electrical Drain/Parasitic Load Test
7. The vehicle has received a new battery without a proper charge.
8. There has been extended engine cranking due to poor engine mechanical conditions.
9. The built-in hydrometer has been incorrectly interpreted. Refer to Battery Hydrometer Displays Dark or Yellow Dot. Battery Hydrometer Displays Dark or Yellow Dot
10. Increased parasitic load has caused continued current draw on the battery. Refer to Battery Electrical Drain/Parasitic Load Test. Battery Electrical Drain/Parasitic Load Test
11. Faulty mechanical conditions exist in the electrical system, such as pinched wires.