GM Service Manual Online
For 1990-2009 cars only

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.


Object Number: 190959  Size: SF

Maintenance Free Battery


Object Number: 405476  Size: SH

The original equipment battery is a maintenance free type battery. The original equipment maintenance free type battery has the following components:

    • A hydrometer (1) which is an indicator of the battery state of charge
    • A negative terminal (2)
    • A retaining tab (3)
    • A positive terminal (4)
    • A battery core (5) which contains lead plates and sulfuric acid.

There are no vent plugs in the battery. The battery is completely sealed except for two small vent holes. These vent holes allow the small amount of hydrogen gas that is produced in the battery to escape.

The battery has three main functions as a source of energy:

    • Engine cranking
    • Voltage stabilizer
    • Alternate source of energy with generator overload.

Specification Label

The battery specification label is located on the battery and contains information about:

    • The battery load test rating
    • The original equipment catalog number
    • The recommended replacement model number

Battery Ratings

A battery has two ratings:

    • Reserve capacity
    • Cold cranking amperage

Important: When the battery must be replaced, install a new battery that meets or exceeds the original equipment battery cold cranking amperage and reserve capacity ratings (recommended replacement model number). Refer to the battery specification label on the original battery or Battery Usage .

Reserve Capacity

Reserve capacity is the amount of time (in minutes) it takes for a fully charged battery, discharged at a constant rate of 25 amperes and a constant temperature of 27°C (80°F), to reach a terminal voltage of 10.5 V. Refer to Battery Usage for the reserve capacity rating of the original equipment battery.

Cold Cranking Amperage

The cold cranking amperage is an indication of the ability of the battery to crank the engine at cold temperatures. The cold cranking amperage rating is the minimum amperage the battery must maintain for 30 seconds at -18°C (0°F) while maintaining at least 7.2 volts. Refer to Battery Usage for the cold cranking amperage rating of the original equipment battery for this vehicle.