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Home >> Audi >> 2021 >> Q3 Premium Plus >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 1 (Cooling System [CWZA,DAJB,CJSA,CJSB,CJXB,CJXC,CNSB,CNTC,CHHB,CJXF,CYFB,CJXD,CJHA,CJXG,CJHB,CULB,CULC,DBRA,CHHC,DJHA,DJHB,DJJA,DBSA,DHHA,DKTB,DLRA,DNUF,DNUE,DKTA,DKTC,DKXA]) >> 19 Cooling System >> Coolant System/Coolant >> Cooling System, Checking For Leaks
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Cooling System, Checking For Leaks

WARNING: This page is about a different variant/trim than selected.

Special tools and workshop equipment required 

Procedure 

CAUTION:

The Cooling System Is under Pressure When the Engine Is Warm. 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.

-- Open the coolant expansion tank cap.

-- Position the : VAG1274B  with the : VAG1274/8  on the coolant expansion tank.

GWWA19-12246Courtesy of AUDI OF AMERICA, LLC

-- Generate approximately 1.0 bar (14.5 psi) pressure using the cooling system tester hand pump.

-- If the pressure falls, search for leaks and correct the malfunction.

CAUTION:

There is a risk of scalding due to hot steam and hot coolant.

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

- Reducing the pressure: press the pressure release valve on the cooling system tester until the pressure gauge displays a value of 0.

Pressure Relief Valve in Cap, Checking

Cap, Version 1: 

Fig 1: Coolant Expansion Tank
GWWA19-12304Courtesy of AUDI OF AMERICA, LLC

-- Position the : VAG1274B  with the : VAG1274B/15  on the cap.

-- Generate approximately 2.0 bar (29 psi) pressure using the cooling system tester hand pump.

GWWA19-12214Courtesy of AUDI OF AMERICA, LLC

Blue Cap 

-- If the pressure relief valve does not react as specified, replace the cap.

Black Cap 

-- If the pressure relief valve does not react as specified, replace the cap.

Cap, Version 2: 

GWWA19-12607Courtesy of AUDI OF AMERICA, LLC

-- Position the : VAG1274B  with the : VAG1274/9  on the cap.

GWWN19-11195Courtesy of AUDI OF AMERICA, LLC

-- Generate pressure with the cooling system tester hand pump.

Blue Cap 

-- If pressure relief valve does not open as specified, replace the cap.

Black Cap 

-- If pressure relief valve does not open as specified, replace the cap.