For 1990-2009 cars

Caution: Batteries generate hydrogen gas, which is extremely flammable and may explode violently if ignited by a spark or a flame. Battery acid is extremely corrosive and causes severe personal injury if the acid comes into contact with the skin, and blindness if the acid comes into contact with the eyes. In order to avoid severe personal injury, use extreme caution when servicing the battery or battery-related components.

1. A maintenance free battery is standard on all vehicles. There are no vent plugs in the cover. The battery is completely sealed except for two small vent holes in the side. These vent holes allow the small amount of gas that is produced in the battery to escape.
2. The battery has three functions in the electrical system:

• | Provides a source of energy for engine cranking

• | Voltage stabilizer for the electrical system

• | provides energy for a limited time when the electrical load exceeds the output of the generator

3. The battery specification label contains important information about the following:

• | The test ratings

• | The original model number

• | The recommended replacement model number

• | The cold cranking Amps (CCA)

### Battery Diagnosis

If the battery tests good but still fails to perform satisfactorily, the following are some of the more common causes:

• | A vehicle accessory was left on overnight.

• | The driving speeds have been slow with frequent stops (stop-and-go driving).

• | The electrical load has exceeded the generator output (particularly with the addition of aftermarket equipment).

• | Existing conditions in the charging system, including the following possibilities:

- | An electrical short

- | A slipping belt

- | A bad generator

- | A bad generator voltage regulator

• | The battery has not been properly maintained, including the following situations:

- | A failure to keep the terminals tight

- | A failure to keep the terminals clean

- | A loose battery hold-down

• | Existing mechanical conditions in the electrical system, such as any short or pinched wires, attributing to power failure.

• | The car is in storage for extended periods of time.

• | Plug fouling, causing extended cranking periods.

• | The hydrometer has been read incorrectly.

• | There has been an insufficient Ampere-hour charge rate for a discharged battery.

• | There is a burned out charge indicator bulb causing a NO CHARGE condition.

• | There is a continuous current draw on the battery through excessive parasitic drain.

• | The battery is old.