Diagnostic Aids
Caution: Refer to Battery Disconnect Caution in the Preface section.
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 a failed test on a good battery.
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 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 negative battery cable. |
| 2. | Disconnect the positive battery cable. |
| 3. | Install the test adapters on the terminals. |
| 4. | Follow the instructions for testing the battery outside of the vehicle. |
| • | If a REPLACE BATTERY result is obtained for a battery that is below 4°C (40°F), perform the following steps: |
| 1. | Disconnect the negative battery cable. |
| 2. | Disconnect the positive battery cable. |
| 3. | Allow the battery to sit in a warm place (above 15°C (60°F) for 6 hours. |
| 4. | Install the approved adapters. |
| 5. | Follow the instructions for testing the battery outside of the vehicle. |
| 6. | Replace the battery only if the second test shows a REPLACE BATTERY result. |
For warranty purposes, use the test code from the second test.
| • | 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 negative battery cable. |
| 2. | Disconnect the positive battery cable. |
| 3. | Install the approved adapters. |
| 4. | Follow the instructions for testing the battery outside of the vehicle. |
| 5. | 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, nuts, and washers as adapters when testing the battery. |
| Use the test adapters that are provided with the J 42000 tester or GM part number 12303040 terminal adapters. If the adapters that are provided with the J 42000 tester require replacement, only use adapters with the GM part number 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. |
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.Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Inspect the battery for a cracked, broken, or damaged case, which may indicated by battery acid leakage. Is the battery OK? | -- | Go to Step 2 | Go to Step 19 | ||||||
2 | Compare the Cold Cranking Amperage (CCA) and Reserve Capacity (RC) of the battery to the original battery or Original Equipment (OE) specification. Refer to Battery Usage Does the battery meet or exceed the specifications? | -- | Go to Step 3 | Go to Step 19 | ||||||
3 | Does the hydrometer display a yellow dot? | -- | Go to Step 4 | Go to Step 5 | ||||||
4 | Tap the hydrometer lightly on top with the handle of a small screwdriver to dislodge any air bubbles inside the battery. Does the hydrometer still display a yellow dot? | -- | Go to Step 19 | Go to Step 5 | ||||||
5 |
Does the negative connector rotate? | -- | Go to Step 6 | Go to Step 7 | ||||||
6 | Use a torque wrench in order to verify the torque to loosen the negative battery terminal bolt. Is the torque above the specified value? | 10 N·m | Go to Step 8 | Go to Step 7 | ||||||
7 |
Caution: Refer to Battery Disconnect Caution in the Preface section. Disconnect the negative battery cable. Is the cable disconnected? | -- | Go to Step 9 | -- | ||||||
8 |
Caution: Refer to Battery Disconnect Caution in the Preface section. Ensure the negative battery cable is disconnected. Inspect for the following conditions and repair as needed:
Is the repair complete? | -- | Go to Step 9 | -- | ||||||
9 | Rotate the positive battery cable connector clockwise with light finger pressure. Does the positive connector rotate? | -- | Go to Step 10 | Go to Step 11 | ||||||
10 | Use a torque wrench in order to verify the torque to loosen the positive battery terminal bolt. Is the torque above the specified value? | 10 N·m | Go to Step 12 | Go to Step 11 | ||||||
11 |
Caution: Refer to Battery Disconnect Caution in the Preface section. Disconnect the positive battery cable. Is the cable disconnected? | -- | Go to Step 13 | -- | ||||||
12 |
Caution: Refer to Battery Disconnect Caution in the Preface section.
Is the repair complete? | -- | Go to Step 13 | -- | ||||||
13 |
Are the metal connecting parts clean and in good condition? | -- | Go to Step 14 | -- | ||||||
14 |
Is the cable bolt properly tightened? | -- | Go to Step 15 | -- | ||||||
15 |
Is the cable bolt properly tightened? | -- | Go to Step 16 | -- | ||||||
16 |
Important: Make sure all electrical loads are turned OFF.
Did the tester pass the battery? | -- | Go to Step 17 | Go to Step 18 | ||||||
17 |
Did you complete this action? | -- | Battery OK | -- | ||||||
18 |
Replace the battery. Refer to Battery Replacement . Did you complete the replacement? | -- | Battery OK | -- | ||||||
19 | Replace the battery. Refer to Battery Replacement . Did you complete the replacement? | -- | Battery OK | -- |
