GM Service Manual Online
For 1990-2009 cars only

Caution: Batteries produce explosive gases. Batteries contain corrosive acid. Batteries supply levels of electrical current high enough to cause burns. Therefore, in order to reduce the risk of personal injury while working near a battery, observe the following guidelines:

   • 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.
      - Flush any contacted areas with water immediately and thoroughly.
      - Get medical help.

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. Refer to Electrolyte Freezing.

Notice: Turn OFF the ignition when connecting or disconnecting the battery cables, the battery charger or the jumper cables. Failure to do so may damage the PCM or other electronic components.

  1. Do the following in order to maintain the battery state of charge while storing the vehicle for more than 30 days:
  2. • 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.
  3. When it is time to reconnect the battery, use the following procedure:
  4. • 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 N·m (11 lb ft).

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

    • 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.