REFRESH CHARGING WITH Battery Charger :VAS5903

WARNING: This page is about a different car, the 2024 Audi SQ7, 2024 Audi Q7, 2023 Audi SQ7, and 2023 Audi Q7. However, it is still accessible from the selected car via links, so may be relevant.

Special tools and workshop equipment required

Battery Charger:VAS5900

Fig 1: Battery Charger VAS5903
Courtesy of AUDI

WARNING:

Risk of injury. Follow all warning messages and safety precautions. Refer to WARNINGS AND SAFETY PRECAUTIONS .

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.

CAUTION:

"Refresh charging" is not permitted for VW vehicles, because voltage surges can damage the on-board electronics.

The Battery -A- must always be disconnected from the vehicle electrical system when using the "Refresh charging" mode.

CAUTION:

Always set the mode that corresponds to the Battery -A- during the charging process. Refer to the Battery Charger:VAS5903 Operating Instructions.

"Refresh Charging" is suitable for wet batteries, which must be filled with distilled water.

Do not use "refresh charging" mode on maintenance-free wet batteries.

"Refresh charging (Refr)" mode is only used on Batteries -A- that are possibly defective (sulfation). The Battery -A- is then charged to the maximum specific gravity of the electrolyte and the plates are reactivated (removal of sulfation layer).

NOTE:

The Battery -A- temperature must be at least 10 °C (50 °F).

Procedure

-- Turn off the ignition and all electrical consumers and remove the ignition key.

-- Connect the Battery Charger:VAS5903 to the power supply. The last selected operation mode is shown on the display. Refer to Battery Charger .

-- Set the battery type with the INFO button.

Fig 2: Identifying Battery Charger Displays - Standard Charge (Wet Batteries Or AGM Batteries)

Courtesy of AUDI

The symbol -1- for "refresh - charging wet batteries" or the symbol -2- for "refresh - charging of Gel/Absorbent Glass Mat (AGM) batteries" is indicated in the display.

-- Set the battery capacity (Ah) on the Battery -A- to be charged with the corresponding ↑ button or ↓ button.

-- Connect the red charge terminal (+) to the positive terminal of the Battery -A-.

NOTE:

On vehicles with a Start/Stop function and an installed Battery Monitoring Control Module -J367-, the black charge terminal (-) must be connected to the body ground. The Start/Stop system will malfunction when it is connected to the Battery -A- negative terminal.

-- Connect the black charge terminal (-) to the negative terminal of the Battery -A- /negative connector.

The Battery Charger:VAS5900 recognizes the nominal voltage of the connected Battery -A- (6 V/12 V/24 V) and begins the charging process automatically.

The Battery Charger:VAS5900 begins the "final charging" when the charge level is approximately 80 to 85 % of the battery voltage. The fourth bar is indicated on the display -1-. The Battery -A- is now ready to be used.

Fig 3: Charging Unit Display, Charge Condition Approx. 80 - 85 %

Courtesy of AUDI

NOTE:

A successful "Refresh charge" depends on the degree of sulfation on the Battery -A-.

Possible Malfunctions and How They Are Handled

Displayed voltage does not match the nominal voltage:
-- Hold down the ↑ button or ↓ button until the charging process begins.
Displayed battery voltage does not match rated voltage - charging process has already begun:
-- Press the START/STOP button two times.

-- Hold down the ↑ button or ↓ button until the charging process begins.
The charger does not recognize a Battery -A-, when the battery voltage is less than 2 V:
The display remains unchanged.

The set operating mode and Ampere-hours (Ah) are displayed.

Battery -A- charging, ending

-- Press the START/STOP -button.

-- Remove the charging clamps from the battery terminals.

-- Disconnect the Battery Charger:VAS5903 from the power.