The sealed battery is standard on all cars. There are no vent plugs in the cover. The battery is completely sealed, except for 2 small vent holes in the sides. These vent holes allow the small amount of gas produced in the battery to escape. The battery has the following advantages over conventional batteries:

The battery has 3 major functions in the electrical system. First, the battery provides a source of energy for cranking the engine. Second, the battery acts as a voltage stabilizer for the electrical system. Finally, the battery can, for a limited time, provide energy when the electrical demand exceeds the output of the generator.

A battery has 2 ratings: (1) a reserve capacity rating designated at 27°C (80°F), which is the time a fully charged battery will provide 25 amperes current flow at or above 10.5 volts; (2) a cold cranking amp rating determined under testing at 18°C (0°F), which indicates the cranking load capacity.

The reserve capacity is the maximum length of time it is possible to travel at night with the minimum electrical load and no generator output. Expressed in minutes, reserve capacity (or RC rating) is the time required for a fully charged battery, at a temperature of 27°C (80°F) and being discharged at a current of 25 amperes, to reach a terminal voltage of 10.5 volts.

The cold cranking amperage test is expressed at a battery temperature of 18°C (0°F). The current rating is the minimum amperage, which must be maintained by the battery for 30 seconds at the specified temperature, while meeting a minimum voltage requirement of 7.2 volts. This rating is a measure of cold cranking capacity.

The battery is not designed to last indefinitely. However, with proper care, the battery will provide many years of service.

If the battery tests well, but fails to perform satisfactorily in service for no apparent reason, the following factors may point to the cause of the trouble :

The sealed battery has a built in, temperature compensated hydrometer in the top of the battery. This hydrometer is to be used with the following diagnostic procedure

1. When observing the hydrometer, make sure that the battery has a clean top.
2. Under normal operation, 2 indications can be observed :

•	GREEN DOT VISIBLE--Any green appearance is interpreted as a "green dot", meaning the battery is ready for testing.

•	DARK GREEN DOT IS NOT VISIBLE--If there is a cranking complaint, the battery should be tested. The charging and electrical systems should also be checked at this time.

3. Occasionally, a third condition may appear :

CLEAR OR BRIGHT YELLOW--This means the fluid level is below the bottom of the hydrometer. This may have been caused by excessive or prolonged charging, a broken case, excessive tipping, or normal battery wear. Finding a battery in this condition may indicate high charging by a faulty charging system. Therefore, the charging and the electrical systems may need to be checked if a cranking complaint exists. If the cranking complaint is caused by the battery, replace the battery.

1. Batteries with the green dot showing do not require charging unless they have just been discharged (such as in cranking a vehicle).
2. When charging sealed terminal batteries out of the vehicle, install the adapter kit. Make sure all the charger connections are clean and tight. For best results, batteries should be charged while the electrolyte and the plates are at room temperature. A battery that is extremely cold may not accept current for several hours after starting the charger.
3. Charge the battery until the green dot appears. The battery should be checked every half hour while charging. Tipping or shaking the battery may be necessary to make the green dot appear.
4. After charging, the battery should be load tested. Refer to Battery Inspection/Test .

The time required to charge a battery will vary depending upon the following factors:

Unless this procedure is properly followed, a perfectly good battery may need to be replaced. The following procedure should be used to recharge a completely discharged battery:

1. Measure the voltage at the battery terminals with an accurate voltmeter. If the reading is below 10 volts, the charge current will be very low, and it could take some time before the battery accepts the current in excess of a few milli-amperes. Refer to "Charging Time Required", which focuses on the factors affecting both the charging time required and the rough estimates in the table below. Such low current may not be detectable on ammeters available in the field.
2. Set the battery charger on the high setting.

Important: Some chargers feature polarity protection circuitry, which prevents charging unless the charger leads are correctly connected to the battery terminals. A completely discharged battery may not have enough voltage to activate this circuitry, even though the leads are connected properly, making it appear that the battery will not accept charging current. Therefore, follow the specific charger manufacturer s instruction for bypassing or overriding the circuitry so that the charger will turn ON and charge a low voltage battery.

3. Continue to charge the battery until the charge current is measurable. Battery chargers vary in the amount of voltage and current provided. The time required for the battery to accept a measurable charge current at various voltages may be as follows:

•	If the charge current is not measurable at the end of the above charging times, the battery should be replaced.

•	If the charge current is measurable during the charging time, the battery is good, and charging should be completed in the normal manner.

Important: It is important to remember that a completely discharged battery must be recharged for a sufficient number of ampere hours (AH) to restore the battery to a usable state. As a general rule, using the reserve capacity rating (RC) as the number of ampere hours of charge usually brings the green dot into view.

•	If the charge current is still not measurable after using the charging time calculated by the above method, the battery should be replaced.