Audi A4: Battery

Battery General Information

To guarantee a long service life, the Battery -A- must be checked, serviced and maintained as described in this manual.

The Battery -A- supplies the power to start the engine. The Battery -A- also acts as a power reserve for the entire vehicle electrical system.

  Note

Refer to Self Study Program.

  Caution

In order to prevent damage to the Battery -A- or vehicle, observe the battery type information. Refer to → Chapter "Battery Types".

  WARNING

Risk of injury. Follow all warning messages and Safety Precautions. → Chapter "Warnings and Safety Precautions".

Battery Types

General Information

  Caution

The following described Batteries -A- are maintenance-free Batteries -A-. Do not remove any of the labels on the battery and do not add distilled water. Perform only a visual inspection. Note the chapter on battery testing. Refer to → Chapter "Battery, Checking".

Battery -A- with Visual Indicator

Maintenance-free Battery -A- with fluid electrolyte (wet battery).

  Caution

Do not remove any of the labels on the battery and do not add distilled water. Perform only a visual inspection. Note the chapter on battery testing. Refer to → Chapter "Battery, Checking".

  WARNING

Do not check or charge a Battery -A- when the visual indicator has "no color or is bright yellow". Jump starting must not be used!

There is a risk of explosion during testing, charging or jump starting.

These Batteries -A- must be replaced.

This Battery -A- has a visual indicator. The colors in the visual indicator show the Battery -A- charge and electrolyte level.

Visual indicator color display, checking. Refer to → Chapter "Visual Indicator Color Display, Checking".

EFB-Battery

Maintenance-free Battery -A- with fluid electrolyte (wet battery).

  Caution

Do not remove any of the labels on the battery and do not add distilled water. Perform only a visual inspection. Note the chapter on battery testing.

  WARNING

Do not check or charge a Battery -A- when the visual indicator has "no color or is bright yellow". Jump starting must not be used!

There is a risk of explosion during testing, charging or jump starting.

These Batteries -A- must be replaced.

The Battery -A- is installed in certain Stop/Start vehicles due to special requirements. "EFB" is written on the battery cover to identify this battery.

"EFB" stands for "Enhanced Flooded Battery" (enhanced wet battery).

An EFB battery may only be replaced with another EFB battery.

This Battery -A- has a visual indicator. The colors in the visual indicator show the Battery -A- charge and electrolyte level.

Visual indicator color display, checking. Refer to → Chapter "Visual Indicator Color Display, Checking".

  Note

"EFB" batteries are being used in certain Audi A1 and Audi A3 models from August 2011.

AGM-Battery

Maintenance-Free Battery -A- with Fixed Electrolyte (AGM battery).

Lead-acid battery, where the electrolyte is fixed in an absorbent glass mat (AGM). The Battery -A- is closed and equipped with breather valves.

"AGM" is the English abbreviation for Absorbent Glass Mat.

These Batteries -A- cannot have a visual indicator due to the fixed electrolyte. AGM is on the Battery -A- to identify it.

When replacing an AGM battery, another AGM battery must be installed.

Warnings and Safety Precautions

Dangers When Working with Batteries

Recognizing and Preventing Risks

Batteries -A- present risks. Read the warnings on the Battery -A- label, in the Owner's Manual and in ELSA to prevent these risks.

  WARNING

• Personnel instructed in protection, such as a trainee or an apprentice, may only perform work on vehicle Batteries -A- under supervision of technical personnel, for example, a master automotive technician or a master automotive electrician.
• Acid has strong corrosive properties. If Batteries -A- are handled inappropriately, there is a risk that personal injury may result from exposure to harmful electrolyte influences. Therefore, suitable remedies for acid damage must be kept readily available. Soapy water would be a suitable remedy.
• If electrolyte drips out from the Battery -A-, skin can be burned by acid and the vehicle may be affected by acid erosion and corrosion. It is a possibility that safety-related vehicle components can be damaged.
• When charging and when resting after charging, explosive gas is present. In extreme cases, if the Battery -A- is handled inappropriately, the emitted gases may cause the battery to explode.
• Replace a Battery -A- if the visual indicator has "no color or is bright yellow". They may not be tested or charged and jump starting may not be used. There is a risk of explosion during testing, charging or jump starting.
• Producing sparks by sanding, welding, cutting and open flames, is forbidden. Producing sparks through electrostatic discharge must also be avoided. Always touch the vehicle body before touching the Battery -A-.
• Only perform Battery -A- procedures in suitable and well-ventilated locations.

  WARNING

Pollution risk.

• Old batteries require special disposal. They contain poisonous lead (Pb) and sulfuric acid.
• Follow disposal requirements, only dispose of used batteries in suitable containers at an authorized collection site.

Battery Safety Label

Safety Label on the Battery -A-

1 - When working in the area of the Battery -A-, fire, sparks, open flame are prohibited. Avoid sparks when working with cables and electrical devices, and from electrostatic discharge. Avoid short circuits. For this reason, tools should not be rested on the Battery -A-.

2 - Wear protective eyewear when working on the Battery -A-.

3 - Always keep acid and Batteries -A- out of the reach of children.

4 - Disposal: old batteries require special disposal. They may only be disposed of at a suitable collection facility and only in consideration of legal regulations.

5 - Do not dispose of old batteries in household waste.

6 - When handling Batteries -A-, there is a risk of explosion. Battery -A- charging produces a highly explosive gas mixture.

7 - Always follow instructions on the Battery -A-, in the Parts Catalog and in the Owner's Manual.

8 - Danger of burns: battery acid is severely corrosive, therefore protective gloves and eyewear must be worn when working on the Battery -A-. The Battery -A- must not be tipped because acid may spill from the ventilation openings.

Working on the Airbag System

  WARNING

When working on the airbag system (pyrotechnic components, Airbag Control Module -J234-, wiring), the Ground (GND) cable must be disconnected with the ignition switched on.

Exceptions: On vehicles with a battery in the passenger compartment, the ignition must be switched off.

• Then cover the negative terminal.
• After disconnecting the battery, a wait time of 10 seconds is required.
• The battery must be connected with the ignition switched on.
• There must be no one inside the vehicle when connecting the battery.

Make sure in this case to keep oneself away from the airbag deployment and belt tensioner zones.

If the ignition is not switched on after reconnecting the battery (the indicator lamps in the instrument cluster do not illuminate), the ignition (key/button) may only be switched on while sitting in the driver's seat in the rearmost position.

Battery Post/Terminal

  Caution

In order to prevent damage to the battery terminals and battery posts, observe the following:

• Never use force to attach the battery terminals by hand.
• Do not apply grease to battery posts.
• The battery terminal clamps should be mounted so that the battery terminal sits 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.

Terminal clamp tightening specification. Refer to → Electrical Equipment; Rep. Gr.27; Battery.

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