Battery Not Operating Properly

CAUTION: Refer to Battery Disconnect Caution in Service Precautions.

IMPORTANT: The battery test using the J 42000 Battery Tester requires correct connections to the battery terminals. A failure to obtain the correct connections during the test may result in replacing the battery unnecessarily. Adhere to the following instructions in order to avoid an incorrect diagnosis due to poor connections:

- When testing the vehicle with the battery cables still connected, rock the J 42000 battery tester clips back and forth on the terminal bolt in order to cut through any coating or oxidation that may be present on the bolt. Even new bolts contain a protective coating that may insulate or cause a resistance in the test circuit.

- If it is uncertain that correct connections can be made to the battery terminal bolts in the vehicle, perform the following steps:
1. Disconnect the battery cables. Refer to Battery Negative Cable Disconnect/Connect Procedure.
2. Install the test adapters on the terminals.
3. Follow the instructions for testing the battery outside of the vehicle.

- If a REPLACE BATTERY result is obtained for a battery tested in the vehicle with the battery cables connected, perform the following steps:
1. Disconnect the battery cables. Refer to Battery Negative Cable Disconnect/Connect Procedure
2. Install the approved adapters.
3. Follow the instructions for testing the battery outside of the vehicle.
4. Replace the battery only if the second test shows a REPLACE BATTERY result.
For warranty purposes, use the test code from the second test.

- Use the approved terminal adapters.
Do not use any common bolts or a combination of bolts, nut, and washers as adapters when testing the battery.
Use the test adapters that are provided with the J 42000 battery tester. If the adapters that are provided with the J 42000 battery tester require replacement, only use equivalent adapters. Any other adapters may not contact the correct areas of the battery terminal, causing resistance that may result in an invalid battery test result.
- In order to test the top terminal, threaded stud batteries outside of the vehicle.
Do not connect the tester to the plain threaded terminals.

IMPORTANT: For warranty purposes, always place the test code displayed by the tester on the repair order. The number is a unique identifier that describes the test data for a particular battery at a particular time.

While the test code may occasionally repeat when retesting the same battery, it is more likely that a different code will result each time the battery is tested.

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Battery Not Operating Properly