Battery: Description and Operation

CAUTION: Batteries produce explosive gasses. Batteries contain corrosive acid. Batteries supply levels of electrical current high enough to cause burns. Therefore, to reduce the risk of personal injury while working near a battery:
- Always shield your eyes.
- Avoid leaning over the battery whenever possible.
- Do not expose the battery to open flames or sparks.
- Do not allow battery acid to contact the eyes or the skin.
1. Flush any contacted areas with water immediately and thoroughly.
2. Get medical help.

The maintenance free battery is standard in all GM vehicles. The battery is completely sealed except for two small vent holes in the sides. The vent holes allow a small amount of gas produced in the battery to escape.
The battery provides the following three functions in the electrical system:
- The battery provides a source of energy for cranking the engine.
- The battery acts as a voltage stabilizer for the electrical system.
- The battery can provide energy when the electrical load exceeds the output of the generator, for a limited time.

ELECTROLYTE FREEZING
The freezing point of the battery electrolyte depends on the battery's specific gravity.
Freezing a battery can ruin the battery.
Protect the battery from freezing by keeping the battery fully charged.
With the green dot showing in the built-in hydrometer, the battery will not freeze until the temperature drops below -32°C (-25°F). A fully charged battery will not freeze until the temperature drops below -54°C (-65°F). Refer to Battery Hydrometer Displays Dark or Yellow Dot.

BATTERY RATINGS
The battery specification label contains useful information for servicing the battery. The information includes test ratings, original equipment and recommended replacement part numbers. Refer to Battery Usage.
The battery has two ratings: Cold Cranking Amperage (CCA) and Reserve Capacity.
- Cold Cranking Amperage indicates the battery's ability to crank the engine during cold temperatures.
- The CCA rating is the minimum amperage the battery must maintain for 30 seconds at -18°C (O°F), while staying above 7.2 volts.
- The actual performance of the battery varies with temperature, electrical load, and the condition of the vehicle's electrical condition.

RESERVE CAPACITY
Reserve capacity is the maximum amount of time (in minutes) it will take for a fully charged battery, being discharged at a constant rate of 25 amperes with the temperature remaining at 27°C (80°F), to reach a terminal voltage of 10.5 volts.
- Reserve capacity is an estimate of how long a person may operate the vehicle under the following conditions:
- No generator output
- The headlamps are on
- A minimum electrical load (most accessories are turned off).
- How long the battery will actually last when the vehicle is being driven without generator output depends on the following factors:
- The temperature
- The current draw
- The state of charge
- The condition of the battery

BATTERY (PROTECTION DURING STORAGE)

CAUTION: Batteries produce explosive gasses. Batteries contain corrosive acid. Batteries supply levels of electrical current high enough to cause burns. Therefore, to reduce the risk of personal injury while working near a battery:
- A/ways shield your eyes.
- Avoid leaning over the battery whenever possible.
- Do not expose the battery to open flames or sparks.
- Do not allow battery acid to contact the eyes or the skin.
1. Flush any contacted areas with water immediately and thoroughly.
2. Get medical help.
- Follow each step in the jump starting instructions, exactly.

Always shield your eyes.
- Avoid leaning over the battery whenever possible. Do not expose the battery to open flames or sparks.
- Do not allow battery acid to contact the eyes or the skin.
1. Flush any contacted areas with water immediately and thoroughly.
2. Get medical help.
- Follow each step in the jump starting instructions, exactly.
Certain electronic devices on the vehicle maintain a small continuous current drain (parasitic load) on the battery, such as a PCM or a VCM. A battery that is not used for an extended period of time will discharge. Eventually permanent damage will result. Discharged batteries will also freeze in cold weather.
- Do the following in order to maintain the battery state of charge while storing the vehicle for more than 30 days:
- Ensure that the green dot is visible in the built-in hydrometer.
- Disconnect the negative battery cable to protect the battery from discharge by parasitic current drains.
- When it is time to reconnect the battery, use the following procedure:

NOTICE: Refer to Fastener Notice in Service Precautions. Vehicle Damage Warnings

1. Lightly wire brush any oxidation from the contact face of the battery terminal and the battery post before reattaching the cable.

Tighten
Tighten the battery cable bolt to 15 Nm (11 ft. lbs.).

2. Reset the clock and the push-button tuning radio before the vehicle is put back into service.
- Maintain a high state of charge when the battery cannot be disconnected.
- Establish a regular schedule for recharging the battery every 20-45 days.
- When a battery is found without a green dot visible in the hydrometer, promptly recharge the battery.
- To reduce charging time, use a battery charger that can produce a charging voltage of at least 16 volts.
- Original equipment maintenance free batteries are not damaged by charging rates of 50 amps or more.
- The battery will not be damaged as long as the battery does not spew acid from the vents or get hotter than 52°C (125°F).
- Check the battery being charged every 45-60 minutes.
- If gassing or overheating does occur, reduce the rate of charge, or stop if necessary.
- Avoid overcharging by stopping one hour after the green dot appears in the hydrometer.
- Allow ample charging time. Refer to Battery Charging.
- A battery that has remained in a discharged state for a long period of time is difficult to recharge or may be permanently damaged.

BATTERY TRAY AND HOLD-DOWN RETAINER DESCRIPTION

CAUTION: Batteries produce explosive gasses. Batteries contain corrosive acid. Batteries supply levels of electrical current high enough to cause burns. Therefore, to reduce the risk of personal injury while working near a battery:
- Always shield your eyes.
- Avoid leaning over the battery whenever possible.
- Do not expose the battery to open flames or sparks.
- Do not allow battery acid to contact the eyes or the skin.
1. Flush any contacted areas with water immediately and thoroughly.
2. Get medical help.

The battery tray and the retainer should be clean and free of corrosion before the battery is installed.
The tray should be in good condition so the tray can hold the heavy battery securely and level. Be certain that there are no parts in the tray before installing the battery. Refer to Battery
Prevent the battery from shaking in the tray by tightening the retainer to specifications.

Tighten
Tighten the battery hold down retainer nut to 17 Nm (13 ft. lbs.).