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Home >> Audi >> 2021 >> A4 Quattro Premium Plus, 2.0L Eng VIN B >> Repair and Diagnosis (Single Page) >> Engine Mechanical >> Cooling System (Mechanical) >> Cooling System 2.0L (DPAA) >> 19 Cooling System >> Cooling System/Coolant >> Coolant, Draining, High-Voltage Cooling Circuit

Coolant, Draining, High-Voltage Cooling Circuit

Special tools and workshop equipment required 

Procedure 

CAUTION:

There is a risk of explosion caused by cooling system leaks in the high-voltage battery. This can cause a buildup of explosive gases in the battery housing.

Explosions may cause severe bodily injuries.

- Do not add coolant when the coolant level is low in the coolant expansion tank, until the cause of the leak is corrected.

- If the indicator lamps for "low coolant" and "high-voltage battery error" turn on, move the vehicle outdoors to the specified separate parking area.

- Notify the high-voltage experts for the importer.

GWWA19-13203Courtesy of AUDI OF AMERICA, LLC
CAUTION:

The cooling system is under pressure when the engine is warm. There is a risk of scalding due to hot steam and hot coolant.

Scalding the skin and other parts of the body is possible.

- Wear safety gloves.

- Wear protective eyewear.

- Reduce the pressure by covering the coolant expansion tank cap with a cloth and carefully opening it.

-- Cut the tab on the seal -3- and open the coolant expansion tank cap -1- for the high-voltage system cooling circuit (example illustration).

Fig 5: Identifying VAG1274B & VAG1274/8
GWWA19-12246Courtesy of AUDI OF AMERICA, LLC
CAUTION:

Risk of damaging high-voltage components due to overheating.

- Do not perform high-voltage charging without coolant in the system.

- Label the vehicle accordingly.

-- Position the Cooling System Tester: VAG1274B  with the Cooling System Tester - Adapter: VAG1274/8  on the coolant expansion tank.

-- Create a light pressure of 0.5 bar (7.25 psi) using the hand pump on the cooling system tester.

-- Remove the noise insulation (front). Refer to OVERVIEW - NOISE INSULATION .

Audi A6/A7:

GWWA19-13098Courtesy of AUDI OF AMERICA, LLC

-- Position the Shop Crane - Drip Tray: VAS6208  under the coolant hoses to the Electric Drive Power and Control Electronics -JX1- under the underbody.

-- Lift the clip -arrow-, remove the coolant hose -1- and allow the coolant to drain.

-- Loosen the hose clamp -3-, remove the coolant hose -2- and let the coolant drain out.

-- Clean out the entire coolant circuit with compressed air.

Audi Q5:

GWWA19-13204Courtesy of AUDI OF AMERICA, LLC

-- Place the Shop Crane - Drip Tray: VAS6208  underneath.

-- Loosen the hose clamp -arrow-, remove the coolant hose and let the coolant drain out.

-- Remove the left center and left rear underbody trim panel. Refer to OVERVIEW - UNDERBODY TRIM PANELS .

-- Place the Shop Crane - Drip Tray: VAS6208  underneath.

GWWA19-13205Courtesy of AUDI OF AMERICA, LLC

-- Lift the clip -arrows-, remove the coolant hoses and allow the coolant to drain.

-- Loosen the hose clamp -1- and remove the coolant hose and let the coolant drain out.

-- Clean out the entire coolant circuit with compressed air.

Continuation for All Vehicles: 

-- Reconnect the old coolant hoses and coolant hoses with connector coupling. Refer to Figure.

-- Remove the Cooling System Tester: VAG1274B  from the Cooling System Tester - Adapter: VAG1274/8  .

-- Fill the cooling system. Refer to COOLING SYSTEM, FILLING, HIGH-VOLTAGE SYSTEM COOLING CIRCUIT .