Battery Load Test

CAUTION: Batteries produce explosive gases, contain corrosive acid, and supply levels of electrical current high enough to cause burns. Therefore, to reduce the risk of personal injury when working near a battery:

IMPORTANT: Load testing a battery out of the vehicle requires the use of battery side terminal adapters (AC Delco pant number ST-1201, GM part number 12303040 or equivalent) to ensure good connections.

Do not load test a frozen battery. Replace it instead.
1. Turn the ignition key OFF.
2. Use a DVOM with load OFF to check the voltage across the terminals. With all loads off, and the green dot showing in the hydrometer, the voltage should be 12 volts or higher. If not, replace the battery.
3. With DVOM still attached, connect a battery load tester across the battery terminals.
4. If the battery has been on charge, within the past 24 hours apply a 300 ampere load for 15 seconds to remove surface charge from the battery. Remove the load. (Do not complete this step if the battery has not been recently charged.)
5. Wait 15 seconds to let the battery recover. Apply the specified load located on the battery label or Refer to Battery Usage. Read the voltage after 15 seconds, them remove the load.
6. If the voltage does not drop below the minimum, the battery is good and should be returned to service. (The battery temperature must be estimated by feel and by the temperature the battery has been exposed to for the proceeding few hours). Refer to Battery Temperature. vs. Test Voltage. Electrical Specifications
7. If the voltage drops below the minimum listed, replace the battery.