Tools Required

J 42000  Digital Battery Tester. See Special Tools .

• For best results, use an automatic taper-rate battery charger with a voltage capability of 16 volts.
Fig 1: Identifying Battery Charge Levels
Courtesy of GENERAL MOTORS CORP.
• A battery showing a green dot in the hydrometer (1) does not need to be charged unless the J 42000  Battery Tester has shown that the battery needs to be charged. See Special Tools .
• A battery showing a dark dot in the hydrometer (2) should be charged unless the J 42000  has indicated no charge is needed. See Special Tools .
• Do not charge a battery when the built in hydrometer is clear or yellow in the center (3). Tap the hydrometer lightly in order to dislodge any air bubbles. The bubbles may cause a false indication. If the hydrometer is still clear or yellow, replace the battery.
• The charging area should be well ventilated.
• Do not charge a battery that appears to be frozen; allow the battery to warm to room temperature and test it before charging.