DTC B1C1A:12, B1C1A:13, B1C1B:12, B1C1B:13 [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)]

id0702k2818100

System malfunction location (L.H.D.)	•  B1C1A:12: Driver-side air mix actuator (potentiometer) circuit short to power supply •  B1C1A:13: Driver-side air mix actuator (potentiometer) circuit open •  B1C1B:12: Passenger-side air mix actuator (potentiometer) circuit short to power supply •  B1C1B:13: Passenger-side air mix actuator (potentiometer) circuit open
System malfunction location (R.H.D.)	•  B1C1A:12: Passenger-side air mix actuator (potentiometer) circuit short to power supply •  B1C1A:13: Passenger-side air mix actuator (potentiometer) circuit open •  B1C1B:12: Driver-side air mix actuator (potentiometer) circuit short to power supply •  B1C1B:13: Driver-side air mix actuator (potentiometer) circuit open
Detection condition	•  Malfunction in wiring harness between air mix actuator and climate control unit
Fail-safe	Malfunction determined when IG SW at ON •  Air mix actuator drive signal is stopped right when the malfunction is determined. Malfunction already exists when IG SW turned to ON •  Control based on ambient temperature.
Possible cause	•  Connector or terminal malfunction •  Air mix actuator malfunction •  Open circuit in wiring harness between climate control unit and air mix actuator •  Short to power supply in wiring harness between climate control unit and air mix actuator •  Climate control unit malfunction

Diagnostic Procedure

STEP	INSPECTION		ACTION
1	INSPECT AIR MIX ACTUATOR CONNECTOR •  Switch the ignition off. •  Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITHOUT i-stop)].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) •  Disconnect the air mix actuator connector. (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) •  Inspect the connector and terminals (corrosion, damage, pin disconnection). •  Are the connector and terminals normal?	Yes	Go to the next step.
		No	Repair/replace the connector or terminal. After repair procedure, go to the next step.
2	INSPECT AIR MIX ACTUATOR •  Inspect the air mix actuator. (See AIR MIX ACTUATOR INSPECTION [FULL-AUTO AIR CONDITIONER].) •  Is it normal?	Yes	Go to the next step.
		No	Replace the air mix actuator. (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) Go to the next step.
3	INSPECT AIR MIX ACTUATOR (POTENTIOMETER) CIRCUIT FOR OPEN •  Disconnect the climate control unit connector and the air mix actuator connector. •  Inspect for continuity between the following terminals (wiring harness-side): Driver-side (L.H.D.)/Passenger-side (R.H.D.) ―  Climate control unit terminal 1L—air mix actuator terminal G ―  Climate control unit terminal 1P—air mix actuator terminal F ―  Climate control unit terminal 1W—air mix actuator terminal E Passenger-side (L.H.D.)/Driver-side (R.H.D.) ―  Climate control unit terminal 1L—air mix actuator terminal E ―  Climate control unit terminal 1R—air mix actuator terminal F ―  Climate control unit terminal 1W—air mix actuator terminal G •  Is there continuity?	Yes	Go to the next step.
		No	Repair the wiring harness. Go to the next step.
4	INSPECT AIR MIX ACTUATOR (POTENTIOMETER) SHORT TO GROUND •  Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITHOUT i-stop)].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) •  Switch the ignition ON (engine off or on). •  Measure the voltage at the following terminals (wiring harness-side): Driver-side ―  Climate control unit terminal 1P (L.H.D.) / 1R (R.H.D.) Passenger-side ―  Climate control unit terminal 1R (L.H.D.) / 1P (R.H.D.) •   Is the voltage 0V?	Yes	The system is normal at present. Go to the next step.
		No	Repair/replace the malfunctioning vehicle wiring harness. After repair procedure, go to the next step.
5	VERIFY CLIMATE CONTROL UNIT CONNECTOR CONDITION •  Switch the ignition off. •  Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITHOUT i-stop)].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) •  Inspect the connector and terminals (corrosion, damage, pin disconnection). •  Are the connector and terminals normal?	Yes	Go to the next step.
		No	Repair/replace the malfunctioning vehicle wiring harness, connector, or terminal. After repair procedure, go to the next step.
6	VERIFY THAT SAME DTC IS NOT OUTPUT AGAIN •  Reconnect the disconnected connectors. •  Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITHOUT i-stop)].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) •  Clear the past malfunction from memory. •  Verify DTCs. •  Is DTC B1C1A:12, B1C1A:13, B1C1B:12, B1C1B:13 output?	Yes	Repeat the inspection from Step 1. •  If the malfunction does not recur, go to the next step. •  If the malfunction recurs, replace the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) Go to the next step.
		No	Go to the next step.
7	VERIFY THAT NO OTHER DTCs ARE PRESENT •  Verify other DTCs displayed. •  Are any other DTCs output?	Yes	Perform the corresponding DTC inspection.
		No	DTC troubleshooting completed.