DTC B1B71:11, B1B71:13 [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)]


id0702k2817100


With Dual Type Climate Control Unit

System malfunction location

•  B1B71:11: Evaporator temperature sensor circuit short to ground
•  B1B71:13: Evaporator temperature sensor circuit open
Detection condition
•  Malfunction in wiring harness between evaporator temperature sensor and climate control unit
Fail-safe function
•  A/C output OFF is controlled when the evaporator temperature sensor input value is at 0 °C {32 °F}.
Possible cause
•  Connector or terminal malfunction
•  Evaporator temperature sensor malfunction
•  Open circuit in wiring harness between the following terminals:
―  Climate control unit terminal 1L—evaporator temperature sensor terminal B
―  Climate control unit terminal 1J—evaporator temperature sensor terminal A
•  Short to ground in wiring harness between the following terminals:
―  Climate control unit terminal 1L—evaporator temperature sensor terminal B
•  Climate control unit malfunction


Diagnostic Procedure

STEP

INSPECTION

ACTION

1
INSPECT EVAPORATOR TEMPERATURE SENSOR CONNECTOR
•  Switch the ignition off.
•  Disconnect the evaporator temperature sensor connector.
•  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 Step 6.
2
INSPECT EVAPORATOR TEMPERATURE SENSOR
•  Inspect the evaporator temperature sensor.
•  Is it normal?
Yes
Go to the next step.
No
Replace the evaporator temperature sensor.
Go to Step 6.
3
INSPECT EVAPORATOR TEMPERATURE SENSOR CIRCUIT FOR OPEN CIRCUIT
•  Disconnect the climate control unit connector.
•  Inspect for continuity between the following terminals (wiring harness-side):
―  Climate control unit terminal 1L—evaporator temperature sensor terminal B
―  Climate control unit terminal 1J—evaporator temperature sensor terminal A
•  Is there continuity?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and evaporator temperature sensor terminal.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 6.
4
INSPECT EVAPORATOR TEMPERATURE SENSOR CIRCUIT FOR SHORT TO GROUND
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground:
―  Climate control unit terminal 1L
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and evaporator temperature sensor terminal.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to ground.
Go to Step 6.
No
Go to the next step.
5
VERIFY CLIMATE CONTROL UNIT CONNECTOR CONDITION
•  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.
6
VERIFY THAT SAME DTC IS NOT OUTPUT AGAIN
•  Reconnect the disconnected connectors.
•  Clear the DTC from the climate control unit memory using the M-MDS.
•  Perform the DTC inspection for the climate control unit using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the climate control unit.
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 displayed?
Yes
Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
No
DTC troubleshooting completed.


With Single Type Climate Control Unit

System malfunction location

•  B1B71:11: Evaporator temperature sensor circuit short to ground
•  B1B71:13: Evaporator temperature sensor circuit open
Detection condition
•  Malfunction in wiring harness between evaporator temperature sensor and climate control unit
Fail-safe function
•  A/C output OFF is controlled when the evaporator temperature sensor input value is at 0 °C {32 °F}.
Possible cause
•  Connector or terminal malfunction
•  Evaporator temperature sensor malfunction
•  Open circuit in wiring harness between the following terminals:
―  Climate control unit terminal J—evaporator temperature sensor terminal B
―  Climate control unit terminal E—evaporator temperature sensor terminal A
•  Short to ground in wiring harness between the following terminals:
―  Climate control unit terminal J—evaporator temperature sensor terminal B
•  Climate control unit malfunction


Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT EVAPORATOR TEMPERATURE SENSOR CONNECTOR
•  Switch the ignition off.
•  Disconnect the evaporator temperature sensor connector.
•  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 Step 6.
2
INSPECT EVAPORATOR TEMPERATURE SENSOR
•  Inspect the evaporator temperature sensor.
•  Is it normal?
Yes
Go to the next step.
No
Replace the evaporator temperature sensor.
Go to Step 6.
3
INSPECT EVAPORATOR TEMPERATURE SENSOR CIRCUIT FOR OPEN CIRCUIT
•  Disconnect the climate control unit connector.
•  Inspect for continuity between the following terminals (wiring harness-side):
―  Climate control unit terminal J—evaporator temperature sensor terminal B
―  Climate control unit terminal E—evaporator temperature sensor terminal A
•  Is there continuity?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and evaporator temperature sensor terminal.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 6.
4
INSPECT EVAPORATOR TEMPERATURE SENSOR CIRCUIT FOR SHORT TO GROUND
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground:
―  Climate control unit terminal J
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and evaporator temperature sensor terminal.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to ground.
Go to Step 6.
No
Go to the next step.
5
VERIFY CLIMATE CONTROL UNIT CONNECTOR CONDITION
•  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.
6
VERIFY THAT SAME DTC IS NOT OUTPUT AGAIN
•  Reconnect the disconnected connectors.
•  Clear the DTC from the climate control unit memory using the M-MDS.
•  Perform the DTC inspection for the climate control unit using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the climate control unit.
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 displayed?
Yes
Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
No
DTC troubleshooting completed.