AIR CONDITIONING SYSTEM PROBLEM SYMPTOMS TABLE

Note

Before replacing the main body ECU (multiplex network body ECU) or certification ECU (smart key ECU assembly), refer to Service Bulletin.

Tech Tips


  • Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

  • Inspect the fuses and relays related to this system before inspecting the suspected areas below.

Air Conditioning System
Symptom Suspected Area Link
All functions of the air conditioning system do not operate IG power source circuit

Click here

Back-up power source circuit

Click here

LIN communication circuit

Click here

Air conditioning amplifier assembly

Click here

Heat pump ECU assembly

Click here

Air flow Control: No blower operation Blower motor circuit

Click here

LIN communication circuit

Click here

Air conditioning amplifier assembly

Click here

Heat pump ECU assembly

Click here

Air flow control: No blower control Blower motor circuit

Click here

LIN communication circuit

Click here

Air conditioning amplifier assembly

Click here

Heat pump ECU assembly

Click here

Air flow control: Insufficient air flow Blower motor circuit

Click here

Air conditioning amplifier assembly

Click here

Temperature control: Cooling effectiveness is poor Compressor operates but cooling effectiveness is poor (High pressure reduction performed)

Click here

Refrigerant pressure*3

Click here

Refrigerant pressure*4

Click here

Compressor operates but cooling effectiveness is poor (High pressure reduction not performed)

Click here

Compressor with motor assembly

Click here

Air conditioning amplifier assembly

Click here

Heat pump ECU assembly

Click here

Temperature control: No cool air comes out Refrigerant volume -
Refrigerant pressure*3

Click here

Refrigerant pressure*4

Click here

Compressor operates but cooling effectiveness is poor (High pressure reduction performed)

Click here

Air conditioner pressure sensor circuit

Click here

Air conditioner pressure sensor

Click here

Air mix damper control servo motor circuit (for driver side)

Click here

Air mix damper control servo motor circuit (for front passenger side)

Click here

Evaporator temperature sensor

Click here

Cooler (room temp. sensor) thermistor

Click here

Thermistor assembly

Click here

Air conditioning wire

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Driver side air mix)

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Front passenger side air mix)

Click here

Air conditioning harness assembly

Click here

Compressor with motor assembly

Click here

Air conditioning amplifier assembly

Click here

Hybrid vehicle control ECU

Click here

ECM

Click here

Heat pump ECU assembly

Click here

Temperature control: No warm air comes out Refrigerant volume -
Refrigerant pressure*3

Click here

Refrigerant pressure*4

Click here

Air conditioner pressure sensor circuit

Click here

Compressor operates but heating effectiveness is poor (A/C switch off)

Click here

Compressor operates but heating effectiveness is poor (A/C switch on)

Click here

Air mix damper control servo motor circuit (for driver side)

Click here

Air mix damper control servo motor circuit (for front passenger side)

Click here

Cooler (room temp. sensor) thermistor

Click here

Ambient temperature sensor circuit

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Driver side air mix)

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Front passenger side air mix)

Click here

Air conditioning harness assembly

Click here

Air conditioning amplifier assembly

Click here

Hybrid vehicle control ECU

Click here

ECM

Click here

Temperature control: Output air is warmer or cooler than the set temperature or response is slow Refrigerant volume -
Refrigerant pressure*3

Click here

Refrigerant pressure*4

Click here

Air conditioner pressure sensor circuit

Click here

Cooler (room temp. sensor) thermistor

Click here

Thermistor assembly

Click here

Air mix damper control servo motor circuit (for driver side)

Click here

Air mix damper control servo motor circuit (for front passenger side)

Click here

Air inlet damper control servo motor circuit

Click here

Heater radiator unit sub-assembly

Click here

Compressor operates but cooling effectiveness is poor (High pressure reduction not performed)

Click here

Compressor operates but heating effectiveness is poor (A/C switch off)

Click here

Compressor operates but heating effectiveness is poor (A/C switch on)

Click here

Air conditioning wire

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Driver side air mix)

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Front passenger side air mix)

Click here

No. 1 blower damper servo sub-assembly

Click here

Air conditioning harness assembly

Click here

Air conditioning amplifier assembly

Click here

Hybrid vehicle control ECU

Click here

ECM

Click here

Heat pump ECU assembly

Click here

Temperature control: No temperature control (only MAX COLD or MAX HOT) Cooler (room temp. sensor) thermistor

Click here

Thermistor assembly

Click here

LIN communication circuit

Click here

Air mix damper control servo motor circuit (for driver side)

Click here

Air mix damper control servo motor circuit (for front passenger side)

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Driver side air mix)

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Front passenger side air mix)

Click here

Air conditioning harness assembly

Click here

Air conditioning amplifier assembly

Click here

Temperature control: Output air temperature is different between left and right registers (the set temperature is the same for both) Refrigerant volume -
Refrigerant pressure*3

Click here

Refrigerant pressure*4

Click here

Air mix damper control servo motor circuit (for driver side)

Click here

Air mix damper control servo motor circuit (for front passenger side)

Click here

Automatic light control sensor

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Driver side air mix)

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Front passenger side air mix)

Click here

Air conditioning harness assembly

Click here

Air conditioning amplifier assembly

Click here

No air inlet control LIN communication circuit

Click here

Air inlet damper control servo motor circuit

Click here

No. 1 blower damper servo sub-assembly

Click here

Air conditioning harness assembly

Click here

Air conditioning amplifier assembly

Click here

No air flow mode control LIN communication circuit

Click here

Air outlet damper control servo motor circuit (for driver side)

Click here

Air outlet damper control servo motor circuit (for front passenger side)

Click here

No. 1 air conditioning radiator damper servo sub-assembly (Driver side mode)*1

Click here

No. 1 air conditioning radiator damper servo sub-assembly (Front passenger side mode)*2

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Driver side mode)*2

Click here

No. 2 air conditioning radiator damper servo sub-assembly (Front passenger side mode)*1

Click here

Air conditioning harness assembly

Click here

Air conditioning amplifier assembly

Click here

Diagnostic trouble codes (DTCs) are not recorded. Set mode is cleared when the power switch is turned off Back-up power source circuit

Click here

Air conditioning amplifier assembly

Click here


Remote Air Conditioning System
Symptom Suspected Area Link
Remote air conditioning system cannot be operated using an electrical key transmitter sub-assembly or smartphone (air conditioning system and hybrid control system are normal) Wireless door lock control system

Click here

Read the Data List (FR Door Courtesy SW, FL Door Courtesy SW, RR Door Courtesy SW, RL Door Courtesy SW, Back Door Courtesy SW)

Click here

Read the Data List (Hood Courtesy SW)

Click here

Read the Data List (Start Switch1, Start Switch2)

Click here

Read the Data List (IGB Request)

Click here

Read the Data List (FR Door Lock Pos, FL Door Lock Pos, RR-Door Lock Pos SW, RL-Door Lock Pos SW)

Click here

Operation check (start, stop)

Click here

Certification ECU (smart key ECU assembly) -
Main body ECU (multiplex network body ECU)

Click here

Use simulation method to check

Click here

Remote air conditioning system cannot be operated but the doors can be locked using an electrical key transmitter sub-assembly or smartphone (air conditioning system and hybrid control system are normal) Read the Data List (FR Door Courtesy SW, FL Door Courtesy SW, RR Door Courtesy SW, RL Door Courtesy SW, Back Door Courtesy SW)

Click here

Read the Data List (Hood Courtesy SW)

Click here

Read the Data List (Start Switch1, Start Switch2)

Click here

Read the Data List (IGB Request)

Click here

Read the Data List (Stop Light SW)

Click here

Read the Data List (Shift Position)

Click here

Certification ECU (smart key ECU assembly) -
Main body ECU (multiplex network body ECU)

Click here

Use simulation method to check

Click here

Remote air conditioning system stops immediately after it is started Operation check (start, stop)

Click here

Use simulation method to check

Click here

Air conditioning amplifier assembly

Click here

Remote air conditioning system operates unintentionally (electrical key transmitter sub-assembly and smartphone are not operated) Operation check (start, stop)

Click here

Air conditioning amplifier assembly

Click here

Main body ECU (multiplex network body ECU)

Click here

Certification ECU (smart key ECU assembly) -
Hybrid vehicle control ECU

Click here

Remote air conditioning system cannot be stopped using electrical key transmitter sub-assembly or smartphone Operation check (stop)

Click here

Air conditioning amplifier assembly

Click here

Main body ECU (multiplex network body ECU)

Click here

Certification ECU (smart key ECU assembly) -
Hybrid vehicle control ECU

Click here