GM Service Manual Online
For 1990-2009 cars only

Caution: Wear a safety face shield when load testing a battery to prevent possible personal injury.

Tools Required

J 39200 Digital Multimeter


    Object Number: 167883  Size: SH

    Important: Do not load test a frozen battery.

  1. Connect the J 39200 and a battery load tester (2) across the battery terminals.
  2. Apply a 300 ampere load for 15 seconds in order to remove the surface charge from the battery (1).
  3. Remove the load.
  4. Wait for 15 seconds in order to let the battery recover.

  5. Object Number: 167881  Size: SH
  6. Apply the load specified on the battery label or half the cold cranking ampere rating to the battery.
  7. Measure the battery voltage after 15 seconds.
  8. Remove the load.
  9. If the voltage does not drop below the minimum voltage listed below, the battery is good and should be returned to service. (Estimate the battery temperature by feel and by the temperature the battery had been exposed to for the preceding few hours).
  10. If the voltage drops below the minimum listed below, replace the battery.

Battery Load Test Voltage

Estimated Temperature

Minimum Voltage

21°C (70°F)

9.6 VDC

10°C (50°F)

9.4 VDC

0°C (30°F)

9.1 VDC

-10°C (15°F)

8.8 VDC

-18°C (0°F)

8.5 VDC

Below -18°C (0°F)

8.0 VDC