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For 1990-2009 cars only

Special Tools

J 42000 Battery Tester

Diagnostic Aids

Important: 

   • Failure to properly understand the battery and its function could lead to a misdiagnosis and unneeded repairs. For detail information, refer to Battery Description and Operation and Battery Common Causes of Malfunction .
   • If testing an AGM battery with the J 42000 , add 100 to the CCA rating of the battery and enter that amount into the tester when prompted for the CCA rating. For instance, if the AGM batteries CCA rating is 500 amps, enter 600 into the J 42000 . Perform this modification only if the J 42000 does not ask if you are testing an AGM battery. If these instructions are not followed when testing an AGM battery, an invalid test result and invalid test code will be obtained on the J 42000 .
   • The battery test using the J 42000 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.

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 an Out-of-Vehicle test.
    • 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.
        4. Follow the instructions for an Out-of-Vehicle test.
        5. Replace the battery only if the Out-of-Vehicle test shows a REPLACE BATTERY or BAD CELL-REPLACE result. This prevents battery replacements that are due only to faulty battery cable connections.
    • Use the correct terminal adapters.
    • Do not use any common bolts or a combination of bolts, nuts, and or washers as adapters when testing the battery.
    • Use the test adapters that are provided with the J 42000 or P/N 12303040 terminal adapters. If the adapters that are provided with the J 42000 require replacement, use P/N 12303040. Other adapters may not contact the correct areas of the battery terminal, causing a resistance that may result in an invalid battery test result.

Step

Action

Values

Yes

No

Caution: Refer to Battery Disconnect Caution in the Preface section.

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. If the battery is replaced due to failing the test, only an Out-of-Vehicle test code is valid for warranty purposes.

1

Inspect the battery for a cracked, broken, or damaged case, which may be indicated by battery acid leakage.

Is the battery OK?

--

Go to Step 2

Go to Step 15

2

Compare 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.

Does the battery meet or exceed the specifications?

--

Go to Step 3

Go to Step 15

3

  1. Turn OFF the ignition.
  2. Attempt to rotate the negative battery cable connector clockwise with light finger pressure.

Does the negative connector rotate?

--

Go to Step 4

Go to Step 5

4

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 (88 lb in)

Go to Step 9

Go to Step 8

5

Attempt to rotate the positive battery cable connector clockwise with light finger pressure.

Does the positive connector rotate?

--

Go to Step 7

Go to Step 6

6

Important: Ensure that all of the electrical loads are turned OFF.

  1. Install the J 42000 Battery Tester.
  2. Follow the directions supplied with the tester for an In-Vehicle test.
  3. Follow any directions displayed on the tester.
  4. If the tester calls for charging the battery, refer to Battery Charging .

Did the tester pass the battery?

--

Go to Step 14

Go to Step 8

7

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 (88 lb in)

Go to Step 10

Go to Step 8

8

  1. Disconnect the negative battery cable.
  2. Disconnect the positive battery cable.
  3. Clean and wire brush the lead face of both battery terminals and the metal contact rings in both cable connectors.
  4. Remove the bolts from the cable connectors in order to provide access to the connector rings as needed.
  5. If either of the battery terminals or the cable rings are excessively damaged or corroded, replace as needed.

Did you complete the repair?

--

Go to Step 11

--

9

  1. Disconnect the negative battery cable.
  2. Inspect for the following conditions and repair as needed:
  3. • The cable bolt is too long or deformed at the end.
    • There is foreign material present inside the nut in the battery terminal.
    • Damage to the battery terminal face or cable connector ring

Did you complete the repair?

--

Go to Step 10

--

10

  1. Disconnect the positive battery cable.
  2. Inspect for the following conditions and repair as needed:
  3. • The cable bolt is too long or deformed at the end.
    • There is foreign material present inside the nut in the battery terminal.
    • Damage to the battery terminal face or cable connector ring

Did you complete the repair?

--

Go to Step 11

--

11

Important: Ensure that both battery cables are disconnected and proper adapters are installed in the battery terminals.

  1. Install the J 42000 .
  2. Follow the directions supplied with the tester for an Out-of-Vehicle test.
  3. Follow any directions displayed on the tester.
  4. If the tester calls for charging the battery, refer to Battery Charging .

Did the tester pass the battery?

--

Go to Step 12

Go to Step 15

12

  1. Press the CODE button on the J 42000 .
  2. For warranty purposes, write the displayed code on the repair order.

Did you complete this action?

--

Go to Step 13

--

13

  1. Connect the positive battery cable to the batteries positive terminal.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Tighten the positive battery cable bolt to the specified value.
  4. Connect the negative battery cable to the battery negative terminal.
  5. Tighten the negative battery cable bolt to the specified value.

Are the cable bolts properly tightened?

17 N·m (13 lb ft)

Battery OK

--

14

  1. Press the CODE button on the J 42000 .
  2. For warranty purposes, write the displayed code on the repair order.

Did you complete the replacement?

--

Battery OK

--

15

Replace the battery. Refer to Battery Replacement .

Did you complete the replacement?

--

Battery OK

--