A/C cooling performance, testing Audi TT 8N рестайлинг

A/C cooling performance, testing

Test requirements

1. Radiator and condenser clean (clean if necessary)
2. Ribbed belt OK and correctly tensioned
3. All air ducts, covers and seals OK and properly installed
4. Air flow through dust and pollen filter not obstructed by dirt

1. Heating and A/C unit properly sealed (when fresh air blower is at maximum speed setting, no additional air is drawn in; air delivery is via vents only)
2. Vehicle not standing in direct sunlight
3. Expansion valve insulation properly installed and not damaged.
4. Engine at normal operating temperature

1. All instrument panel vents open
2. Engine running and A/C control head -E87- set to "AUTO" mode
3. Compressor switched on (LED in "ECON" button not lit up)
4. Temperature selection "LO"

1. A/C clutch -N25- engages compressor
2. Coolant fan(s) operate depending on system version noted below

Note. Various A/C refrigerant pressure monitoring/control and coolant fan control versions are possible in conjunction with Coolant Fan Control (FC) Module -J293- Vehicles equipped with A/C pressure switch -F129-: -V7- comes on and runs at speed 1 Vehicles equipped with high pressure switch -G65- and Coolant Fan Control (FC) Module -J293- version "1": -V7- comes on and runs at speed 1 Vehicles equipped with high pressure switch -G65- and Coolant Fan Control (FC) Module -J293- version "2": -V7- comes on and runs at speed 1 after refrigerant system pressure has reached 12 bar. Fresh air blower -V2- run at maximum speed Fresh air/recirculated air flap moved to "recirculated air" setting (within 1 minute of starting the engine) Air should come out of the instrument panel vents Both temperature flaps in "cooling" position

Note. If any of the above test requirements is not obtained, check DTC memory. Refer to Diagnostic Trouble Code (DTC) Memory, checking (function 02) and perform output Diagnostic Test Mode (DTM). Refer to Output Diagnostic Test Mode (DTM) (function 03) .

Preparation

1. Check DTC Memory and eliminate any malfunctions that may be displayed. Refer to «Diagnostic Trouble Code (DTC) Memory, checking (function 02)»(/audi/tt/8n-2003-2006/remont/ac-compressor/#heating-air-conditioning__diagnostic-trouble-code-dtc-memory-checking) .
2. Perform basic setting (Refer to «Basic Setting (function 04)»(/audi/tt/8n-2003-2006/remont/ac-compressor/#heating-air-conditioning__basic-setting-function-04) ) and check control module coding (Refer to «VAG 1551 Scan Tool (ST), VAS 5051 Vehicle Diagnostic Testing and Information System, connecting and selecting functions»(/audi/tt/8n-2003-2006/remont/ac-compressor/#heating-air-conditioning__vag-1551-scan-tool-st-vas) ).
3. Close front hood and sunroof.
4. Measure ambient temperature.

1. Close doors and windows.

Testing

1. Switch ignition on.
2. Select "AUTO" mode on A/C control head -E87- and switch temperature setting to "LO"
3. Start engine.

1. A/C clutch engaged, compressor runs.

1. Press button for recirculated air.

1. LED in button lights.

1. Increase engine speed to 2000 RPM (timed period begins).
2. Measure temperature of air delivered by instrument panel vents.

Scheme 94

1. Compare measured values with graph.

A - Temperature of air from center instrument panel vents

B - Measured ambient temperature

C - Permissible temperature range for air from vents

After 5 minutes (depending on ambient temperature) the temperature of air from the center instrument panel vents should settle to within tolerance range -C- on the graph.

If specified values are not obtained. Refer to Identifying malfunctions if specified values are not obtained .