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Hissing from vents and slow loss of refrigerant

Q: How to fix Hissing from vents and slow loss of refrigerant in Toyota Prius II?

Evaporator/condenser leak verification and repair. Replacing your damaged electric compressor with a new or professionally refurbished OEM Denso component. Absolutely fill the system with only ND-11 dielectric oil (POE) using dedicated machines or machines completely free from PAG oil residues.

in Toyota Prius II (2004-2009)

Symptoms

No cold air from vents

DTC error codes

P0AA6

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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

1,8 HSD

Refrigerant: R134a Amount (g): 470g Oil: ND11 POE b.d. Prius Oil (ml): b.d.ml

Standard

Refrigerant: R134a Amount (g): 420 – 480g Oil: ND11 POE b.d. Prius Oil (ml): b.d.ml

(NHW11)

Refrigerant: R134a Amount (g): 450 – 550g Oil: PAG PAO 68 lub PAG ISO 46 Oil (ml): 120ml

See full specification

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