What are the symptoms of Unusual noise and metallic grinding when A/C is on in SEAT Cupra Leon?

No cold air from vents. Unusual noises when A/C is turned on. Hissing from vents

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Unusual noise and metallic grinding when A/C is on

Q: How to fix Unusual noise and metallic grinding when A/C is on in SEAT Cupra Leon?

Replacement of the condenser and the MANDATORY installation of the optional protective grid (Honeycomb grid: 1K0 820 746, Clips: 3D0 867 646). Never replace the condenser in a Golf 7 or Cupra without adding an OEM mesh. The grille clips behind the lower grill and physically blocks the stones. Otherwise, the new condenser will fail after a month.

in SEAT Cupra Leon (2010-2022)

Symptoms

No cold air from vents
Unusual noises when A/C is turned on
Hissing from vents

DTC error codes

Low pressure

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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

IV - (KL)

Refrigerant: R1234yf Amount (g): 430-480g Oil: PAG YF ISO 46 Oil (ml): 120 - 140ml

III - (5F)

Refrigerant: R134a Amount (g): 450-500g Oil: PAG 46 Oil (ml): 120 - 140ml

II kompresor Denso 7SEU17C

Refrigerant: R134a Amount (g): 500 – 550g Oil: PAG PAO 68 lub PAG ISO 46 Oil (ml): 130 – 150ml

See full specification

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