Dtc B1412 Ambient Temperature Sensor Circuit

Vehicle Interior. Corolla. Zre142 Aze141
Heating Air Conditioning. Corolla. Zre142 Aze141

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK CAN COMMUNICATION SYSTEM

READ VALUE USING TECHSTREAM

CHECK HARNESS AND CONNECTOR (AMBIENT TEMPERATURE SENSOR CIRCUIT)

INSPECT COMBINATION METER

INSPECT AMBIENT TEMPERATURE SENSOR

DTC B1412 Ambient Temperature Sensor Circuit


DESCRIPTION

The ambient temperature sensor is installed in front of the condenser. This sensor detects the temperature outside the cabin and sends the appropriate signals to the A/C amplifier via the CAN communication system.

DTC No.
DTC Detection Condition
Trouble Area
B1412
Open or short in ambient temperature sensor circuit
  1. Ambient temperature sensor
  2. Harness or connector between ambient temperature sensor and combination meter
  3. Combination meter
  4. A/C amplifier
  5. CAN communication system

WIRING DIAGRAM


Corolla. Zre142 Aze141.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc B1412 Ambient Temperature Sensor Circuit


INSPECTION PROCEDURE

1.CHECK CAN COMMUNICATION SYSTEM

  1. Use the Techstream to check if the CAN communication system is functioning normally.

    Result:
    Result
    		Proceed to
    CAN DTC is not output
    		A
    CAN DTC is output
    		B


B
GO TO CAN COMMUNICATION SYSTEM (COROLLA_ZRE142 RM000000WI60ACX.html)
A


2.READ VALUE USING TECHSTREAM

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Enter the following menus: Body Electrical / Air Conditioner / Data List.

  1. Check the value(s) by referring to the table below.


Air Conditioner
Tester Display
Measurement Item/Range
Normal Condition
Diagnostic Note
Ambient Temp Sensor
(Ambi Temp Sens)
Ambient temperature sensor / Min: -23.3°C (-9.94°F), Max: 65.95°C (150.71°F)
Actual ambient temperature displayed
Open in circuit: -23.3°C (-9.94°F)
Short in circuit: 65.95°C (150.71°F)
OK:
The display is as specified in the "Normal Condition" column.

Result:

Result
Proceed to
NG
A
OK (When troubleshooting according to Problem Symptoms Table)
B
OK (When troubleshooting according to the DTC output)
C


B
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (COROLLA_ZRE142 RM000001M2W05PX.html)

C
REPLACE AIR CONDITIONING AMPLIFIER (COROLLA_ZRE142 RM000002XMC01VX.html)
A


3.CHECK HARNESS AND CONNECTOR (AMBIENT TEMPERATURE SENSOR CIRCUIT)


    Corolla. Zre142 Aze141.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc B1412 Ambient Temperature Sensor Circuit

  1. Disconnect the connector from the combination meter.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    E46-9 (TX1+) - E46-23 (TEMP)
    		25°C (77°F)
    		1.60 to 1.80 kΩ
    E46-9 (TX1+) - E46-23 (TEMP)
    		40°C (104°F)
    		0.80 to 1.00 kΩ
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Combination Meter)


NG
Go to step 5
OK


4.INSPECT COMBINATION METER

  1. Temporarily replace the combination meter with a known good one (COROLLA_ZRE142 RM0000024D7032X.html).

    HINT:
    Since the combination meter cannot be inspected while it is removed from the vehicle, replace the combination meter with a known good one and check that the condition returns to normal.

  1. Check for DTCs.

    Result:
    Result
    		Proceed to
    DTC B1412 is not output
    		A
    DTC B1412 is output
    		B


B
REPLACE AIR CONDITIONING AMPLIFIER (COROLLA_ZRE142 RM000002XMC01VX.html)
A

REPLACE COMBINATION METER (COROLLA_ZRE142 RM0000024D7032X.html)

5.INSPECT AMBIENT TEMPERATURE SENSOR

  1. Remove the ambient temperature sensor.



    Corolla. Zre142 Aze141.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc B1412 Ambient Temperature Sensor Circuit

  1. Disconnect the connector from the ambient temperature sensor.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A23-1 - A23-2
    		10°C (50°F)
    		3.00 to 3.73 kΩ
    A23-1 - A23-2
    		15°C (59°F)
    		2.45 to 2.88 kΩ
    A23-1 - A23-2
    		20°C (68°F)
    		1.95 to 2.30 kΩ
    A23-1 - A23-2
    		25°C (77°F)
    		1.60 to 1.80 kΩ
    A23-1 - A23-2
    		30°C (86°F)
    		1.28 to 1.47 kΩ
    A23-1 - A23-2
    		35°C (95°F)
    		1.00 to 1.22 kΩ
    A23-1 - A23-2
    		40°C (104°F)
    		0.80 to 1.00 kΩ
    A23-1 - A23-2
    		45°C (113°F)
    		0.65 to 0.85 kΩ
    A23-1 - A23-2
    		50°C (122°F)
    		0.50 to 0.70 kΩ
    A23-1 - A23-2
    		55°C (131°F)
    		0.44 to 0.60 kΩ
    A23-1 - A23-2
    		60°C (140°F)
    		0.36 to 0.50 kΩ
    NOTICE:
    1. Hold the sensor only by its connector. Touching the sensor may change the resistance value.
    2. When measuring, the sensor temperature must be the same as the ambient temperature.
    HINT:
    As the temperature increases, the resistance decreases (see the graph).
    Text in Illustration
    *a
    		Component without harness connected
    (Ambient Temperature Sensor)
    *b
    		Sensing Portion
    *c
    		Resistance (kΩ)
    *d
    		Allowable Range
    *e
    		Temperature (°C (°F))


NG
REPLACE AMBIENT TEMPERATURE SENSOR (COROLLA_ZRE142 RM000002XMI01CX.html)
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR (AMBIENT TEMPERATURE SENSOR - COMBINATION METER)