Battery With Visual Indicator

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WARNING:

If the "Visual Indicator" is colorless or light yellow: Do not check or charge the battery. Do not perform a jump start. There is danger of explosion! The battery must be replaced. replace the battery. Refer to BATTERY, REMOVING AND INSTALLING .

NOTE:

The "visual indicator" -arrow- provides information about the fluid levels and the charge level for the battery being checked.

Fig 1: Identifying "Magic Eye" On Battery

Courtesy of AUDI OF AMERICA, LLC

Determining the state of charge via the color on the "Visual Indicator" is not permitted. To do this, use the corresponding check program in the diagnostic tester. Refer to BATTERY, CHECKING LEVEL USING GUIDED FAULT FINDING .

As the "visual indicator" is only located in a battery cell, only the battery electrolyte level for this battery cell can be checked.

-- Make sure the battery and the terminal clamps are secure. Tighten them if necessary. Refer to BATTERY, CHECKING FOR SECURE FIT .

-- Perform a visual inspection of the battery housing and check for the following:

Corrosion on or damage to the battery pole
Damage to the housing

Before checking electrolyte level:

-- Carefully tap on the "Visual Indicator" with the handle of a screwdriver.

NOTE:

Bubbles can build up under the "Visual Indicator" when the battery is charging and also while driving, causing the color displayed to be incorrect. Gently tapping on the "Visual Indicator" dissolves these bubbles.

-- Read the battery electrolyte level present in the color display. Two different results are possible:

Color display	Battery level
Black or green	Battery electrolyte level is OK
Colorless or light yellow	Battery electrolyte level is too low. Battery must be replaced.