GM Service Manual Online
For 1990-2009 cars only

Certain electronic devices on the vehicle maintain a small continuous current drain (parasitic load) on the battery.

If the engine of the vehicle is not started for 30 days, the battery may reach a low state of charge. If the battery is repeatedly allowed to reach a low state of charge, permanent battery damage may result. A battery that remains in a low state of charge for a long period of time may be difficult to recharge or permanently damaged.

Battery Protection During Vehicle Storage

In order to maintain the battery state of charge while storing the vehicle for more than 30 days:


    Object Number: 1057  Size: SH
  1. Make sure that the green dot is visible in the battery hydrometer (1). If a green dot is not visible, refer to Battery Check .
  2. Disconnect the battery ground (negative) cable in order to protect the battery from discharge caused by parasitic current drains. Refer to Battery Negative Cable Disconnection and Connection .

Important: 

If the battery cannot be disconnected, establish a regular schedule for charging the battery every 20-45 days. Maintain a high state of charge for the battery.