How to fix Slow loss of refrigerant or A/C system leakage in BMW 440i?

Finding a boriga leak in the front of the car. Replacing the leaky small stone cooler, adding fluid, clearing the codes and voila, the cold returns to the A/C.

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Slow loss of refrigerant or A/C system leakage

in BMW 440i (2016-2022)

Symptoms

No cold air from vents

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Technical diagnosis (Premium)

Recognized technical fault:

Auxiliary controller voltage instability detected

Technical analysis

Detailed analysis of HVAC controller operation parameters, CAN bus data readings, and diagnostic signal waveforms. Purchase PRO access or log in to read the full fault analysis.

Confirmed solution

Complete step-by-step repair procedure including module non-volatile memory reset, sensor calibration, and correct wiring routing. Unlock the full report to see the instruction.

Parts needed

Filters ferrite anti-interference / noise suppressor
Auxiliary starting battery (depending on cell status)

Workshop hacks

Important workshop tips for mechanics regarding bypasses without expensive control module replacement and manufacturer software service bulletins.

TSB / TPI service bulletins

TSB-24-HVAC-01TPI-2068943/2

A/C Technical Specifications

Refrigerant specifications for this model are available in the catalog.

Open refrigerant database

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Slow loss of refrigerant or A/C system leakage

Symptoms

A/C Technical Specifications

Other problems in 440i

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