Battery Testing

Battery Side Terminal Adapters:

Battery Caution Label:

1. VISUAL INSPECTION
Check for obvious damage, such as a cracked or broken case or cover, that could permit loss of electrolyte. If obvious damage is noted, replace the battery. Determine cause of damage and correct as needed. If not, proceed to Step 2.

Built-In Hydrometer:

2. HYDROMETER CHECK
A. GREEN DOT VISIBLE - Go To Step 3.
B. DARK; GREEN DOT NOT VISIBLE
- Charge the battery as outlined under "Battery Charging", and then proceed to Step 3.
C. CLEAR OR YELLOW DOT
- If the hydrometer is clear or light yellow, the battery is low on electrolyte and should be replaced.

3. LOAD TEST
- Load testing requires use of battery side terminal adapters (AC Delco part number ST-1201, GM part number 12303040 or equivalent) to ensure good connections. Do not load test a frozen battery. Replace it instead.
A. Use a voltmeter to check voltage across terminals. With all loads off, and green dot showing in hydrometer (Step 2), voltage should be 12 volts or higher. If not, replace the battery.
B. With voltmeter still attached, connect a battery load tester across the battery terminals.
C. If battery has been on charge, apply a 300 ampere load for 15 seconds to remove surface charge from the battery. Remove load. (Do not complete this step if battery has not been recently charged).
D. Wait 15 seconds to let battery recover. Apply specified load located on battery label or listed in "Specifications". Read voltage after 15 seconds, then remove load. Electrical Specifications

Battery Temperature VS. Voltage Drop:

E. If voltage does not drop below the minimum listed, 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).
F. If voltage drops below the minimum listed, replace the battery.