Maintenance Free Battery

Maintenance Free Battery

=> [ Battery, with a Visual Indicator ]

=> [ Battery with Visual Indicator, Checking ]

=> [ Absorbent Glass Mat Battery, without Visual Indicator ]

=> [ Absorbent Glass Mat Battery, Checking ]

=> [ Central Venting System ]

=> [ Battery Post/Terminal ]

=> [ Visual Check of the Battery ]

=> [ Electrolyte Level Color, Checking ]

=> [ Battery Electrolyte Level, Checking ]

Only maintenance free batteries conforming to standards "TL82506" (as of December 1997) and "VW75073" (as of August 2001) may be installed.

Risk of injury due to contact with battery acid!

• Observe warning notes and safety precautions. Refer to => [ There is a risk of injury from the
battery acid. ] Lead Acid Battery Warnings and Safety Precautions.

Risk of explosion due to the explosive gas that forms during battery charging.

• Observe warning notes and safety precautions. Refer to => [ Risk of explosion due to the explosive
gas that forms during battery charging. ] Lead Acid Battery Warnings and Safety Precautions.

Battery, with a Visual Indicator

Lead acid batteries with "visual indicators" are filled with electrolyte fluid (wet battery). They do not have sealing plugs for topping off with distilled water.

• If batteries with a "visual indicator" are equipped with sealing plugs for production reasons, the plugs are covered with plastic sheeting.

• The coverings must not be removed and distilled water must not be added.

• Only perform a visual inspection.

The "visual indicator" - arrow - gives information about the electrolyte level and charge condition of the battery by means of a color display.

Risk of explosion on discharged battery with "visual indicator".

• If the "visual indicator" has no color or is light yellow, the battery may not be tested or charged. Jump starting must not be used! There is a risk of explosion during testing, charging or jump starting. The battery must be replaced.

Battery with Visual Indicator, Checking

Risk of injury and explosion!

• Observe warning notes and safety precautions. Refer to => [ Lead Acid Battery Warnings and Safety Precautions ] Lead Acid Battery Warnings and Safety Precautions

Perform Battery Checks in the Following Sequence:

- Visual check. Refer to => [ Visual Check ] Non Maintenance Free Battery, without a Visual Indicator.

- Check the "visual indicator" color display.

- Check the battery electrolyte level.

- Test the battery. Refer to => [ Battery Checking, Vehicles without a Battery Monitoring Control Module or Energy Management Control Module ] Battery Checking, Vehicles without a Battery Monitoring Control Module or Energy Management Control Module or => [ Battery Test via Current Draw ] Battery Checking, Vehicles with a Battery Monitoring Control Module or Energy Management Control Module.

- Additional procedures depends on the result of the battery testing with the battery tester.

Absorbent Glass Mat Battery, without Visual Indicator

• Absorbent Glass Mat (AGM) batteries are deep cycle-resistant and leakproof.

• Lead acid AGM batteries are filled with electrolyte contained in an absorbent glass mat. The battery is closed and equipped with breather valves.

• These batteries cannot have a "visual indicator" due to the fixed electrolyte. AGM batteries are marked with "AGM" on the battery.

• AGM batteries cannot and must not be opened and distilled water must not be added.

• Only perform a visual inspection.

Crash safety is inadequate if the incorrect battery is installed.

• If the vehicle was originally equipped with an AGM battery, another AGM battery must be installed when replacing.

Absorbent Glass Mat Battery, Checking

Risk of injury and explosion!

• Observe warning notes and safety precautions. Refer to => [ Lead Acid Battery Warnings and Safety Precautions ] Lead Acid Battery Warnings and Safety Precautions

Perform Battery Checks in the Following Sequence:

- Visual check. Refer to => [ Visual Check ] Non Maintenance Free Battery, without a Visual Indicator.

- Test the battery. Refer to => [ Battery Checking, Vehicles without a Battery Monitoring Control Module or Energy Management Control Module ] Battery Checking, Vehicles without a Battery Monitoring Control Module or Energy Management Control Module or => [ Battery Test via Current Draw ] Battery Checking, Vehicles with a Battery Monitoring Control Module or Energy Management Control Module.

- Additional procedures depends on the result of the battery testing with the battery tester.

Central Venting System

To prevent the gas that forms in the engine compartment or vehicle interior during battery charging from causing damage or posing a threat to health, the gas is discharged centrally through an opening on the side of the top cover on the battery.

- Make sure the central venting hose or tube is always secured on the battery.

- Make sure the central venting hose or tube is not pinched. Only then can battery be properly vented.

• Newer generation batteries have a fine mesh flame trap at the central venting exit point. The flame trap is a round fiberglass mat approximately 15 mm wide and 2 mm thick that works like a valve. On the one hand, it allows the gas formed during battery charging to vent and on the other hand, prevents the explosive gas in the battery from igniting.

Battery Post/Terminal

To prevent damage to the battery terminals and battery housing, observe the following:

• Battery terminals must not be greased.

• Battery terminal clamps - arrows - must only be installed by hand without applying force.

• Install battery terminal clamps so the terminal is flush with the clamp or protrudes out of it.

• After tightening the battery terminal clamps to the specified torque, the threaded connections must not be tightened again.

Visual Check of the Battery

- Before performing extensive measurements, inspect visually.

• External battery condition;

• Battery connections;

• Secure battery seating.

Risk of explosion, inadequate crash safety, risk of corrosion, shortened service life.

• A loose battery retaining bracket can damage the battery housing and allow battery acid to leak.

• A battery that is mounted incorrectly can sustain vibration damage resulting in damage to the battery plates.

• Tighten the retaining bracket bolt to specification.

Risk of malfunction in the electrical system or wiring burn.

• The wiring connection contact is not guaranteed if the battery terminals are damaged or the battery terminal clamps are loose. Check the condition of the battery terminals; battery terminal clamp and auxiliary clamp tightening specifications.

Electrolyte Level Color, Checking

Procedure

• Because the "visual indicator" is located in only one battery cell, the battery acid level is only checked for that cell.

- To obtain an accurate reading, gently tap the visual indicator - arrow - with a screwdriver handle.

• When charging the battery and while driving, air bubbles can form below the "visual indicator" and result in an incorrect color display. Tapping releases the air bubbles under the "visual indicator".

- Check the battery acid level using the color indicator. Two different displays are possible: