Possible deviation from specified value during the pressure test (5 Of 12)
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Audi SQ5, 2024 Audi Q5 e, 2024 Audi Q5, 2023 Audi SQ5, and 2023 Audi Q5 e. However, it is still accessible from the selected car via links, so may be relevant.
| Possible deviation from specified value during the pressure test |
- High pressure does not increase or only increases slightly above pressure with engine stopped.
- Low pressure does not drop or drops only slightly.
- The required cooling output is not attained in the heater and A/C unit evaporator (and in the evaporator for cooling the high-voltage components).
|
| Possible causes for the deviation from specified value and their solutions |
- No activation of the A/C compressor, the A/C compressor is not driven.
- If one of the valves installed in the refrigerant circuit is faulty or does not work correctly. Refer to
Refrigerant Circuit
(vehicle-specific service information).
- Constriction or obstruction in refrigerant circuit (for example, inside the refrigerant line between the service connection "low pressure side" and the A/C compressor).
-- Check the activation and function of the A/C compressor and service using the Vehicle Diagnostic Tester
in the "Guided Fault Finding" function.-- Check the function and activation of the various valves installed in the refrigerant circuit via the pressure distribution in the refrigerant circuit. Use the Vehicle Diagnostic Tester
in the "Guided Fault Finding" function and refer to
Refrigerant Circuit
(vehicle-specific service information).-- Depending on the results, service the activation or replace the faulty component (A/C compressor, shut-off valve, expansion valve). Refer to the
Refrigerant Circuit
(vehicle-specific service information).-- Check the refrigerant circuit lines. If the hose or pipe is kinked or constricted, replace this component. Refer to
Refrigerant Circuit
(vehicle-specific service information).-- Run a hand over refrigerant circuit to check for differences in temperature (position of a blockage). If there is a blockage clean the refrigerant circuit (flush with refrigerant R1234yf). Refer to REFRIGERANT CIRCUIT, CLEANING
.-- If a malfunction is determined on the A/C compressor, replace the A/C compressor. Refer to COMPONENTS, REPLACING
.-- If no malfunction can be determined clean the refrigerant circuit (flush with refrigerant R1234yf). Refer to REFRIGERANT CIRCUIT, CLEANING
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| Final Procedures |
| -- Charge the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, CHARGING .-- Repeat the test. Refer to ELECTRICALLY-DRIVEN A/C COMPRESSOR, CHECKING PRESSURE WITH A/C SYSTEM SWITCHED ON . |