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A/C Control Module And Air RECIRCULATION Door Motor, Checking Function

Special tools and workshop equipment required

Test Box 105 Pin V.A.G 1598/42-1 and Test Adapter V.A.G 1598/47
Voltage Tester V.A.G 1527 B

-- Remove the glove compartment. Refer to Removal and Installation .

-- Remove A/C Control Module -J301-, refer to HEATER AND A/C SYSTEM CONTROLS .

-- Connect the A/C control module to vehicle wiring harness via V.A.G 1598/47.

-- Connect V.A.G 1598/42-1 to V.A.G 1598/47.

-- Switch ignition on.

-- Turn rotary switch for air distribution -B- into air distribution to instrument panel vents position.

Fig 1: Identifying A/C Control Module

GWWA87-10275

Courtesy of AUDI OF AMERICA, LLC

-- Fresh/recirculating air button -F- is not operated (fresh air mode, button indicator lamp does not light up).

Fig 2: Identifying Recirculation Flap Motor And Components

GWWA80-0250

Courtesy of AUDI OF AMERICA, LLC

-- Connect a V.A.G 1527 B to the V.A.G 1598/47 between terminals 9 and 10 (connector -C-).

Fig 3: Identifying A/C Control Module And Connectors

GWWA87-10276

Courtesy of AUDI OF AMERICA, LLC

-- Operate fresh/recirculating air button (button indicator lamp lights up).

-- Ground (GND) is applied at terminal 9 for a short time and B+ is applied at terminal 9 for a short time.

Fig 4: Identifying Recirculation Flap Motor And Components

GWWA80-0250

Courtesy of AUDI OF AMERICA, LLC

NOTE:

B+ is applied only for a certain time period after operating the fresh/recirculating air button, when this time has elapsed the control motor is only still actuated over a certain duty cycle (lamp in V.A.G 1527 B only continues to blink on briefly).
The illustration above shows the arrangement for testing on a vehicle without A/C system, disregard connector -A- (in magnified area) and V.A.G 1527 B -B- on vehicles with A/C system.

-- Operate fresh/recirculating air button -F- (recirculating air, button indicator lamp goes out).

Fig 5: Identifying A/C Control Module

GWWA87-10275

Courtesy of AUDI OF AMERICA, LLC

NOTE:

By pressing fresh/recirculating air button -F-, A/C Control Module changes the voltage supply to Recirculation Door Motor -V113- (B+ and GND are interchanged).

-- Check voltage at connector -C- between terminals 9 and 10 e.g. using V.A.G 1527 B -B- (to Fresh/Recirculating Air Door Motor -V154-).

Fig 6: Identifying A/C Control Module And Connectors

GWWA87-10276

Courtesy of AUDI OF AMERICA, LLC

-- Ground is applied at terminal 10 for a short time and B+ is applied at terminal 9 for a short time.

-- Recirculation Door Motor -V113- and thus the recirculation door moves into fresh air mode position (recirculating air intake opening -C- is closed).

Fig 7: Identifying Recirculation Flap Motor And Components

GWWA80-0250

Courtesy of AUDI OF AMERICA, LLC

If no malfunction is detected during this test:

-- Check fresh/recirculating air door for freedom of movement.

-- Replace the air recirculation door motor. Refer to FRESH/RECIRCULATION AIR DOOR MOTOR .

The function is not OK:

-- Check wire connection between A/C control module and Recirculation Door Motor for open circuit or short circuit. Refer to the appropriate SYSTEM WIRING DIAGRAMS information.

-- Check voltage supply and Ground (GND) connection to A/C control module.

-- Replace A/C control module, refer to HEATER CONTROLS .