MICRO 420 BATTERY TESTER (GASOLINE ENGINES)
The Micro 420 automotive battery tester is designed to help diagnose the cause of a defective battery. Follow the instruction service information supplied with the tester to properly diagnose a vehicle. If the instruction service information is not available. See Standard Procedure which includes the directions for using the Micro 420 battery tester.
OTC ONE STEP BATTERY ANALYZER AND CHARGER (DIESEL ENGINES)
The OTC One Step Battery Analyzer and Charger is designed to help diagnose the cause of a defective battery. Follow the instruction service information supplied with the tester to properly diagnose a vehicle.
| 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. | 1. See Standard Procedure for the appropriate test procedures. Repair the excessive ignition-off draw, as required. |
| 2. The charging system is inoperative. | 2. Determine if the charging system is performing to specifications. Refer to Electrical - Engine Systems/Charging - Diagnosis and Testing for the appropriate charging system diagnosis and testing procedures. Repair the inoperative charging system, as required. | |
| 3. The battery is discharged. | 3. Determine the battery state-of-charge using the appropriate battery tester. Charge the inoperative battery, as required. | |
| 4. The battery terminal connections are loose or corroded. | 4. See Diagnosis and Testing for the appropriate battery cable diagnosis and testing procedures. Clean and tighten the battery terminal connections, as required. | |
| 5. The battery has an incorrect size or rating for this vehicle. | 5. See Specifications for the proper battery size and rating. Replace an incorrect battery, as required. | |
| 6. The battery is inoperative. | 6. Test the battery using the appropriate battery tester. Replace the inoperative battery, as required. | |
| 7. The starting system is inoperative. | 7. Determine if the starting system is performing to specifications. Refer to Electrical - Engine Systems/Starting - Diagnosis and Testing for the appropriate starting system diagnosis and testing procedures. Repair the inoperative starting system, as required. | |
| 8. The battery is physically damaged. | 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. | 1. See Specifications for the proper battery size and rating. Replace an incorrect battery, as required. |
| 2. The battery terminal connections are loose or corroded. | 2. See Diagnosis and Testing for the appropriate battery cable diagnosis and testing procedures. Clean and tighten the battery terminal connections, as required. | |
| 3. The electrical system ignition-off draw is excessive. | 3. See Standard Procedure for the appropriate test procedures. Repair the excessive ignition-off draw, as required. | |
| 4. The battery is inoperative. | 4. Test the battery using the appropriate battery tester. Replace the inoperative battery, as required. | |
| 5. The starting system is inoperative. | 5. Determine if the starting system is performing to specifications. Refer to Electrical - Engine Systems/Starting - Diagnosis and Testing for the appropriate starting system diagnosis and testing procedures. Repair the inoperative starting system, as required. | |
| 6. The charging system is inoperative. | 6. Determine if the charging system is performing to specifications. Refer to Electrical - Engine Systems/Charging - Diagnosis and Testing for the appropriate charging system diagnosis and testing procedures. Repair the inoperative charging system, as required. | |
| 7. Electrical loads exceed the output of the charging system. | 7. Inspect the vehicle for aftermarket electrical equipment which might cause excessive electrical loads. | |
| 8. Slow driving or prolonged idling with high-amperage draw loads in use. | 8. Advise the vehicle operator, as required. | |
| THE BATTERY WILL NOT ACCEPT A CHARGE. | 1. The battery is inoperative. | 1. Test the battery using the appropriate battery tester. Replace the inoperative battery, as required. |
BATTERY RECONNECTION
Note. This reconnection procedure is to be performed anytime the battery has been disconnected.
- Connect the negative battery cable remote terminal to the remote battery post and tighten the nut. CAUTION: Once the battery has been connected, review and perform the following information as applicable.
ELECTRONIC STABILITY PROGRAM (ESP)
If the vehicle is equipped with ESP, once the battery is reconnected, the Steering Angle Sensor (SAS) in the clockspring needs to be calibrated. The SAS requires calibration anytime the battery or an ABS (ESP) component has been disconnected for any length of time. If the SAS is not calibrated following battery reconnection, the ESP/BAS indicator lamp is illuminated following five ignition cycles indicating the need for calibration.
To calibrate, perform the following
- Start the engine.
- Center the steering wheel.
- Turn the steering wheel all the way to the left until the internal stop in the steering gear is met, then turn the wheel all the way to the right until the opposite internal stop in the steering gear is met.
- Center the steering wheel.
- Stop the engine.
CLEANING
The following information details the recommended cleaning procedures for the battery and related components. In addition to the maintenance schedules found in this service information and the Owner's Manual, it is recommended that these procedures be performed any time the battery or related components must be removed for vehicle service.
Scheme 22
Scheme 23
Scheme 24
- Clean the battery cable terminal clamps (2) of all corrosion. Remove any corrosion using a wire brush (1) or a post and terminal cleaning tool, and a sodium bicarbonate (baking soda) and warm water cleaning solution.
- Clean the battery tray and battery hold-down hardware of all corrosion. Remove any corrosion using a wire brush and a sodium bicarbonate (baking soda) and warm water cleaning solution. Paint any exposed bare metal.
- If the removed battery is to be reinstalled, clean the outside of the battery case (3) and the top cover with a sodium bicarbonate (baking soda) and warm water cleaning solution using a stiff bristle parts cleaning brush (1) to remove any acid film. Rinse the battery with clean water. Ensure that the cleaning solution does not enter the battery cells through the vent holes. If the battery is being replaced. See «Specifications»(ref-353573-S15953684882010011200000) for the factory-installed battery specifications. Confirm that the replacement battery is the correct size and has the correct ratings for the vehicle.
- Clean the battery thermal guard with a sodium bicarbonate (baking soda) and warm water cleaning solution using a stiff bristle parts cleaning brush to remove any acid film.
- Clean any corrosion from the battery terminal posts with a wire brush or a post and terminal cleaner, and a sodium bicarbonate (baking soda) and warm water cleaning solution.
CONVENTIONAL BATTERY - GASOLINE ENGINE
Low-maintenance conventional batteries are used on vehicles equipped with a gasoline engine, these batteries have non-removable battery cell caps. Under normal service, the composition of this battery reduces gassing and water loss at normal charge rates.
Conventional batteries are made up of six individual cells that are connected in series. Each cell contains positive charged cell groups made of lead oxide, and negatively charged cell groups made of sponge lead. The cells are submerged in a sulfuric acid and water solution called electrolyte.
The battery is used to store electrical energy potential in a chemical form. When an electrical load is applied to the battery terminals, an electrochemical reaction occurs within the battery. This reaction causes the battery to discharge electrical current.
The Micro 420 automotive battery tester is designed to help diagnose the cause of a defective battery. Follow the instruction service information supplied with the tester to properly diagnose a vehicle. If the instruction service information is not available refer to Standard Procedure , which includes the directions for using the Micro 420 battery tester.
The OTC One Step Battery Analyzer and Charger is designed to help diagnose the cause of a defective battery. Follow the instruction information supplied with the tester to properly diagnose a vehicle.
| WARNING | If the battery shows signs of freezing, leaking or loose posts, do not test, assist-boost, or charge. The battery may arc internally and explode. Personal injury and/or vehicle damage may result. |
| WARNING | Explosive hydrogen gas forms in and around the battery. Do not smoke, use flame, or create sparks near the battery. Personal injury and/or vehicle damage may result. |
| WARNING | The battery contains sulfuric acid, which is poisonous and caustic. Avoid contact with the skin, eyes, or clothing. In the event of contact, flush with water and call a physician immediately. Keep out of the reach of children. |
| WARNING | Never exceed 14.4 volts when charging a spiral cell battery. Personal injury and/or battery damage may result. |
A battery that will not accept a charge is faulty, and must be replaced. Further testing is not required. A fully-charged battery must be tested to determine its cranking capacity. A battery that is fully-charged, but fails the OTC One Step Battery Analyzer and Charger or other load test, is faulty and must be replaced.
Note. Completely discharged batteries may take several hours to accept a charge. Refer to Standard Procedure for the proper battery charging procedures.
SPIRAL CELL BATTERY CHARGING
| WARNING | Never exceed 14.4 volts when charging a spiral cell battery. Personal injury and/or battery damage may result. |
Vehicles equipped with a diesel engine utilize a unique spiral cell battery. This battery has a maximum charging voltage that must not be exceeded in order to restore the battery to its full potential, failure to use the following spiral cell battery charging procedure could result in damage to the battery or personal injury.
Battery charging is the means by which the battery can be restored to its full voltage potential. A battery is fully-charged when
- OTC One Step Battery Analyzer and Charger special tool number OT-3641 or equivalent tester indicates battery is OK.
- Open-circuit voltage of the battery is 12.65 volts or above.
- Battery passes Load Test multiple times.
| WARNING | If the battery shows signs of freezing, leaking, loose posts or low electrolyte level, do not test, assist-boost, or charge. The battery may arc internally and explode. Personal injury and/or vehicle damage may result. |
| WARNING | Explosive hydrogen gas forms in and around the battery. Do not smoke, use flame, or create sparks near the battery. Personal injury and/or vehicle damage may result. |
| WARNING | The battery contains sulfuric acid, which is poisonous and caustic. Avoid contact with the skin, eyes, or clothing. In the event of contact, flush with water and call a physician immediately. Keep out of the reach of children. |
| CAUTION | Always disconnect and isolate the battery negative cable before charging a battery. Charge the battery directly at the battery terminals. Do not exceed 14.4 volts while charging a battery. |
| CAUTION | The battery should not be hot to the touch. If the battery feels hot to the touch, turn off the charger and let the battery cool before continuing the charging operation. Damage to the battery may result. |
After the battery has been charged to 12.6 volts or greater, perform a load test to determine the battery cranking capacity. If the battery passes a load test, return the battery to service. If the battery fails a load test, it is faulty and must be replaced.
Clean and inspect the battery hold downs, tray, terminals, posts, and top before completing battery service. See Cleaning for the proper battery system cleaning procedures. See Inspection for the proper battery system inspection procedures.
CHARGING A COMPLETELY DISCHARGED SPIRAL CELL BATTERY
| WARNING | Never exceed 14.4 volts when charging a spiral cell battery. Personal injury and/or battery damage may result. |
The following procedure should be used to recharge a completely discharged battery. Unless this procedure is properly followed, a good battery may be needlessly replaced.
Scheme 25
- Measure the voltage at the battery posts with a voltmeter, accurate to 1/10 (0.10) volt. Refer to Battery «Removal»(ref-353573-S13199479202010011200000) and «Installation»(ref-353573-S19841030422010011200000) for access instructions. If the reading is below ten volts, the battery charging current will be low. It could take several hours before the battery accepts a current greater than a few milliamperes. Such low current may not be detectable on the ammeters built into many battery chargers.
- Disconnect and isolate the battery negative cable. Connect the OTC One Step Battery Analyzer and Charger special tool number OT-3641 or equivalent. NOTE: Some battery chargers are equipped with polarity-sensing circuitry. This circuitry protects the battery charger and the battery from being damaged if they are improperly connected. If the battery state-of-charge is too low for the polarity-sensing circuitry to detect, the battery charger will not operate. This makes it appear that the battery will not accept charging current. See the instructions provided by the manufacturer of the battery charger for details on how to bypass the polarity-sensing circuitry.
- Battery chargers vary in the amount of voltage and current they provide. The amount of time required for a battery to accept measurable charging current at various voltages is shown in «SPIRAL CELL BATTERY CHARGE RATE TABLE»(ref-353573-S02070922642010011200000) . If the charging current is still not measurable at the end of the charging time, the battery is faulty and must be replaced. If the charging current is measurable during the charging time, the battery may be good and the charging should be completed in the normal manner.
| Voltage | Minutes |
|---|---|
| 14.4 volts maximum | Up to 10 minutes |
| 13.0 to 14 volts | Up to 20 minutes |
| 12.9 volts or less | Up to 30 minutes |
SPIRAL CELL BATTERY CHARGE RATE TABLE
CHARGING TIME REQUIRED
The time required to charge a battery will vary, depending upon the following factors
- Battery Capacity - A completely discharged heavy-duty battery requires twice the charging time of a small capacity battery.
- Temperature - A longer time will be needed to charge a battery at -18° C (0° F) than at 27° C (80° F). When a fast battery charger is connected to a cold battery, the current accepted by the battery will be very low at first. As the battery warms, it will accept a higher charging current rate (amperage).
- Charger Capacity - A battery charger that supplies only five amperes will require a longer charging time. A battery charger that supplies eight amperes will require a shorter charging time.
- State-Of-Charge - A completely discharged battery requires more charging time than a partially discharged battery. Electrolyte is nearly pure water in a completely discharged battery. At first, the charging current (amperage) will be low. As the battery charges, the specific gravity of the electrolyte will gradually rise.
The Battery Charging Time Table gives an indication of the time required to charge a typical battery at room temperature based upon the battery state-of-charge and the charger capacity.
| Charging Amperage | 5 Amps | 8 Amps |
|---|---|---|
| Open Circuit Voltage | Hours Charging @ 21° C (70° F) | |
| 12.25 to 12.49 | 6 hours | 3 hours |
| 12.00 to 12.24 | 10 hours | 5 hours |
| 10.00 to 11.99 | 14 hours | 7 hours |
| Below 10.00 | 18 hours | 9 hours |
SPIRAL CELL BATTERY CHARGE TIME TABLE
CONVENTIONAL BATTERY CHARGING
| CAUTION | Vehicles equipped with a diesel engine utilize a unique spiral cell battery. This battery has a maximum charging voltage that must be used in order to restore the battery to its full potential, failure to use the spiral cell battery charging procedure could result in damage to the battery or personal injury. See Standard Procedure for the appropriate procedure. |
Battery charging is the means by which the battery can be restored to its full voltage potential. A battery is fully-charged when
- Micro 420 battery tester indicates battery is OK.
- Open-circuit voltage of the battery is 12.65 volts or above.
- Battery passes Load Test multiple times.
| WARNING | If the battery shows signs of freezing, leaking, loose posts, do not test, assist-boost, or charge. The battery may arc internally and explode. Personal injury and/or vehicle damage may result. |
| WARNING | Explosive hydrogen gas forms in and around the battery. Do not smoke, use flame, or create sparks near the battery. Personal injury and/or vehicle damage may result. |
| WARNING | The battery contains sulfuric acid, which is poisonous and caustic. Avoid contact with the skin, eyes, or clothing. In the event of contact, flush with water and call a physician immediately. Keep out of the reach of children. |
| WARNING | If the battery is equipped with removable cell caps, be certain that each of the cell caps is in place and tight before the battery is returned to service. Personal injury and/or vehicle damage may result from loose or missing cell caps. |
| CAUTION | Always disconnect and isolate the battery negative cable before charging a battery. Do not exceed sixteen volts while charging a battery. Damage to the vehicle electrical system components may result. |
| CAUTION | Battery electrolyte will bubble inside the battery case during normal battery charging. Electrolyte boiling or being discharged from the battery vents indicates a battery overcharging condition. Immediately reduce the charging rate or turn off the charger to evaluate the battery condition. Damage to the battery may result from overcharging. |
| CAUTION | The battery should not be hot to the touch. If the battery feels hot to the touch, turn off the charger and let the battery cool before continuing the charging operation. Damage to the battery may result. |
After the battery has been charged to an open-circuit voltage reading of 12.4 volts or greater, retest the battery with the Micro 420 tester or perform a load test to determine the battery cranking capacity. See Standard Procedure for the proper battery test procedures. If the battery passes a load test, return the battery to service. If the battery fails a load test, it is faulty and must be replaced.
Clean and inspect the battery hold downs, tray, terminals, posts, and top before completing battery service. See Cleaning for the proper battery system cleaning procedures. See Inspection for the proper battery system inspection procedures.
CHARGING A COMPLETELY DISCHARGED CONVENTIONAL BATTERY
The following procedure should be used to recharge a completely discharged battery. Unless this procedure is properly followed, a good battery may be needlessly replaced.
Scheme 26
- Measure the voltage at the battery posts with a voltmeter, accurate to 1/10 (0.10) volt. If the reading is below ten volts, the battery charging current will be low. It could take some time before the battery accepts a current greater than a few milliamperes. Such low current may not be detectable on the ammeters built into many battery chargers.
- Disconnect and isolate the battery negative cable. Connect the battery charger leads. Some battery chargers are equipped with polarity-sensing circuitry. This circuitry protects the battery charger and the battery from being damaged if they are improperly connected. If the battery state-of-charge is too low for the polarity-sensing circuitry to detect, the battery charger will not operate. This makes it appear that the battery will not accept charging current. See the instructions provided by the manufacturer of the battery charger for details on how to bypass the polarity-sensing circuitry.
- Battery chargers vary in the amount of voltage and current they provide. The amount of time required for a battery to accept measurable charging current at various voltages is shown in the «CONVENTIONAL BATTERY CHARGE RATE TABLE»(ref-353573-S21686611892010011200000) . If the charging current is still not measurable at the end of the charging time, the battery is faulty and must be replaced. If the charging current is measurable during the charging time, the battery may be good and the charging should be completed in the normal manner.
| Voltage | Minutes |
|---|---|
| 16.0 volts maximum | Up to 10 min. |
| 14.0 to 15.9 volts | Up to 20 min. |
| 13.9 volts or less | Up to 30 min. |
CONVENTIONAL BATTERY CHARGE RATE TABLE
The time required to charge a battery will vary, depending upon the following factors
- Battery Capacity - A completely discharged heavy-duty battery requires twice the charging time of a small capacity battery.
- Temperature - A longer time will be needed to charge a battery at -18° C (0° F) than at 27° C (80° F). When a fast battery charger is connected to a cold battery, the current accepted by the battery will be very low at first. As the battery warms, it will accept a higher charging current rate (amperage).
- Charger Capacity - A battery charger that supplies only five amperes will require a longer charging time. A battery charger that supplies twenty amperes or more will require a shorter charging time.
- State-Of-Charge - A completely discharged battery requires more charging time than a partially discharged battery. Electrolyte is nearly pure water in a completely discharged battery. At first, the charging current (amperage) will be low. As the battery charges, the specific gravity of the electrolyte will gradually rise.
The Conventional Battery Charging Time Table gives an indication of the time required to charge a typical battery at room temperature based upon the battery state-of-charge and the charger capacity.
| Charging Amperage | 5 Amps | 10 Amps | 20 Amps |
|---|---|---|---|
| Open Circuit Voltage | Hours Charging @ 21° C (70° F) | ||
| 12.25 to 12.49 | 6 hours | 3 hours | 1.5 hours |
| 12.00 to 12.24 | 10 hours | 5 hours | 2.5 hours |
| 10.00 to 11.99 | 14 hours | 7 hours | 3.5 hours |
| Below 10.00 | 18 hours | 9 hours | 4.5 hours |
CONVENTIONAL BATTERY CHARGING TIME TABLE
Scheme 27
Note. The Micro 420 battery tester should only be used to test vehicles equipped with gasoline engines. If the vehicle being tested has a diesel engine the OTC, One Step Battery Analyzer and Charger (OTC) special tool number OT-3641 or equivalent should be used to test the battery.
Always use the Micro 420 instruction manual that was supplied with the tester as a reference. If the instruction manual is not available the following procedure can be used
| WARNING | Always wear appropriate eye protection and use extreme caution when working with batteries. Failure to do so may result in serious or fatal injury. |
BATTERY CABLES
A voltage drop test will determine if there is excessive resistance in the battery cable terminal connections or the battery cable. If excessive resistance is found in the battery cable connections, the connection point should be disassembled, cleaned of all corrosion or foreign material, then reassembled. Following reassembly, check the voltage drop for the battery cable connection and the battery cable again to confirm repair.
When performing the voltage drop test, it is important to remember that the voltage drop is giving an indication of the resistance between the two points at which the voltmeter probes are attached. EXAMPLE: When testing the resistance of the battery positive cable, touch the voltmeter leads to the battery positive cable terminal clamp and to the battery positive cable eyelet terminal at the starter solenoid B(+) terminal stud. If you probe the battery positive terminal post and the battery positive cable eyelet terminal at the starter solenoid B(+) terminal stud, you are reading the combined voltage drop in the battery positive cable terminal clamp-to-terminal post connection and the battery positive cable.