Battery Inspection/test
Tools Required
Diagnostic Aids
Caution: Refer to Battery Disconnect Caution in the Preface section.
| • | 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 a failed test on a good battery. |
| • | Use the Out of Vehicle test for each battery when testing a vehicle with dual batteries. |
Follow these instructions in order to avoid an incorrect diagnosis because of connections:
| • | If testing the vehicle with the battery cables still connected, wiggle the J 42000 clips on the terminal bolt. This may cut through any coating or through any 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 correct connections to the battery terminal bolts in the vehicle are in doubt, perform the following steps: |
| 1. | Disconnect the negative battery cable. |
| 2. | Disconnect the positive battery cable. |
| 3. | Install the test adapters on the terminals. |
| 4. | Follow the instructions for testing a removed battery. |
| • | If the tester displays a REPLACE BATTERY or BAD CELL-REPLACE result for a battery tested in the vehicle with the battery cables connected, perform the following steps: |
| 1. | Disconnect the negative battery cable. |
| 2. | Disconnect the positive battery cable. |
| 3. | Install the tester adapters. |
| Important: Always write the test code displayed by the tester on the repair order for any warranty purposes. The number is a unique code that describes the test data for a particular battery at a particular time. The test code may occasionally repeat when you retest the same battery. More often, each test will result in a different code. Use the test code from the second, or Out of Vehicle test. |
| 4. | Follow the instructions for testing a removed battery. |
| 5. | Replace the battery only if the second test shows a REPLACE BATTERY or BAD CELL-REPLACE result. |
Use the test code from the second test for any warranty purposes.
| • | Use the correct terminal adapters. |
| Do not use any common bolts or a combination of bolts, of nuts, and of washers as adapters when testing the battery. |
| Use the test adapters that are provided with the J 42000 or GM P/N 12303040 terminal adapters. If the adapters that are provided with the J 42000 require replacement, use GM P/N 12303040. Any other adapter may not contact the correct areas of the battery terminal, causing a resistance that may result in an invalid battery test result. |
Circuit/system Testing
- Inspect the battery for a cracked, broken, or damaged case, which may be indicated by battery acid leakage.
- Verify the cold cranking amperage (CCA), and reserve capacity (RC) and/or amp hour (AH) rating of the battery to the original battery or original equipment (OE) specification. Refer to Battery Usage .
- Verify that the battery cables are clean and tight. The battery terminal bolts should be torqued as specified in Fastener Tightening Specifications .
- Install the J 42000 and follow directions supplied by the tester.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Battery Positive and Negative Cable Replacement |
