Battery with "magic eye"

WARNING: This page does not describe the selected car, but rather 15 other vehicles, including the 2008 Audi S4, 2008 Audi RS 4, 2008 Audi A4, 2007 Audi S4, and 2007 Audi RS 4. However, it is still accessible from the selected car via links, so may be relevant.

Battery is located in plenum chamber between engine compartment and windshield or in spare wheel well on RS4.

Fig 1: Pushing Cover Over Battery Toward Right And Removing It Upward

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Slide cover over battery to right - arrow 1 - and remove upward - arrow 2 -.

Fig 2: Identifying The Visual Indicator

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The visual indicator - arrow - gives information about electrolyte level and battery charge.

Switch ignition off.

Fig 3: Identifying The Visual Indicator

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Check electrolyte level at visual indicator - arrow -.
Tap lightly on battery housing with a blunt object, air bubbles under the visual indicator can cause a false reading.
Green → battery charge is OK.
Black → no charge or charge too low

No color or yellow → critical electrolyte level has been reached, battery must be replaced → - 27 BATTERY, STARTER, GENERATOR, CRUISE CONTROL

NOTE:

Observe before disconnecting battery → Note before disconnecting battery. .