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Micro 420 Battery Tester: Notes

WARNING: This page is about a different car, the 2004 Chrysler Pacifica. However, it is still accessible from the selected car via links, so may be relevant.

The Micro 420 automotive battery tester is a special service tool, designed to help the dealership technician diagnose the cause of a defective battery. Follow the instruction manual supplied with the tester to properly diagnose a vehicle. If the instruction manual is not available refer to the STANDARD PROCEDURE  in this article, which includes the directions for using the Micro 420 battery tester.

BATTERY SYSTEM DIAGNOSIS

CONDITION POSSIBLE CAUSES CORRECTION
THE BATTERY SEEMS WEAK OR DEAD WHEN ATTEMPTING TO START THE ENGINE.
  1. The electrical system ignition-off draw is excessive.
  2. The charging system is faulty.
  3. The battery is discharged.
  4. The battery terminal connections are loose or corroded.
  5. The battery has an incorrect size or rating for this vehicle.
  6. The battery is faulty.
  7. The starting system is faulty.
  8. The battery is physically damaged.
  1. Refer to the STANDARD PROCEDURE - IGNITION-OFF DRAW TEST  for the proper test procedures. Repair the excessive ignition-off draw, as required.
  2. Determine if the charging system is performing to specifications. Refer to GENERATORS & REGULATORS for additional charging system diagnosis and testing procedures. Repair the faulty charging system, as required.
  3. Determine the battery state-of-charge using the Micro 420 battery tester. Refer to STANDARD PROCEDURE  for additional test procedures. Charge the faulty battery, as required.
  4. Refer to BATTERY CABLES  for the proper battery cable diagnosis and testing procedures. Check and clean and tighten the battery terminal connections, as required.
  5. Refer to SPECIFICATIONS  for the proper size and rating. Replace an incorrect battery, as required.
  6. Test the battery using the Micro 420 battery tester. Refer to the STANDARD PROCEDURE  in this section for additional test procedures. Replace the faulty battery, as required.
  7. Determine if the starting system is performing to specifications. Refer to STARTING for the proper starting system diagnosis and testing procedures. Repair the faulty starting system, as required.
  8. Inspect the battery for loose terminal posts or a cracked and leaking case. Replace the damaged battery, as required.
THE BATTERY STATE OF CHARGE CANNOT BE MAINTAINED.
  1. The battery has an incorrect size or rating for this vehicle.
  2. The battery terminal connections are loose or corroded.
  3. The electrical system ignition-off draw is excessive.
  4. The battery is faulty.
  5. The starting system is faulty.
  6. The charging system is faulty.
  7. Electrical loads exceed the output of the charging system.
  8. Slow driving or prolonged idling with high-amperage draw loads in use.
  1. Refer to SPECIFICATIONS  for the proper specifications. Replace an incorrect battery, as required.
  2. Refer to DIAGNOSIS AND TESTING - BATTERY CABLE  for the proper cable diagnosis and testing procedures. Clean and tighten the battery terminal connections, as required.
  3. Refer to the STANDARD PROCEDURE - IGNITION-OFF DRAW TEST  test procedures. Repair the faulty electrical system, as required.
  4. Test the battery using the Micro 420 battery tester. Refer to the STANDARD PROCEDURE  for additional test procedures. Replace the faulty battery, as required.
  5. Determine if the starting system is performing to specifications. Refer to STARTING for the proper starting system diagnosis and testing procedures. Repair the faulty starting system, as required.
  6. Determine if the charging system is performing to specifications. Refer to GENERATORS & REGULATORS for charging system diagnosis and testing procedures. Repair the faulty charging system, as required.
  7. Inspect the vehicle for aftermarket electrical equipment which might cause excessive electrical loads.
  8. Advise the vehicle operator, as required.
THE BATTERY WILL NOT ACCEPT A CHARGE.
  1. The battery is faulty.
  1. Test the battery using the Micro 420 battery tester.. Charge or replace the faulty battery, as required.
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