DTC B1412: Ambient Temperature Sensor Circuit [10/2018 - ]: Procedure
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- READ VALUE USING TECHSTREAM
- Connect the Techstream to the DLC3.
- Turn the power switch on (IG).
- Turn the Techstream on.
- Enter the following menus: Body Electrical / Air Conditioner / Data List.
- Read the Data List according to the display on the Techstream.
Body Electrical > Air Conditioner > Data List
Tester Display Measurement Item Range Normal Condition Diagnostic Note Ambient Temp Sensor Thermistor assembly Min.: -23.30°C (-9.94°F)
Max.: 65.95°C (150.71°F)Actual ambient temperature displayed Thermistor assembly circuit malfunction - When open circuit: -23.30°C (-9.94°F)
- When short circuit: 65.95°C (150.71°F)
Body Electrical > Air Conditioner > Data List
Tester Display Ambient Temp Sensor OK
The display is as specified in the normal condition column.
Result
Proceed to OK NG
Result:
OK
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]
Result:
NG
See step 2
- INSPECT THERMISTOR ASSEMBLY
- Remove the thermistor assembly.
Refer to REMOVAL [10/2018 - ]
- Inspect the thermistor assembly.
Refer to INSPECTION [10/2018 - ]
Result
Proceed to OK NG
Result:
NG
REPLACE THERMISTOR ASSEMBLY. Refer to REMOVAL [10/2018 - ]
Result:
OK
See step 3
- Remove the thermistor assembly.
- CHECK HARNESS AND CONNECTOR (THERMISTOR ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)
- Disconnect the F50 air conditioning amplifier assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A9-1 (+) - F50-13 (TAM) Always Below 1 Ω A9-2 (-) - F50-2 (SG-2) Always Below 1 Ω A9-1 (+) or F50-13 (TAM) - Other terminals and body ground Always 10 kΩ or higher A9-2 (-) or F50-2 (SG-2) - Other terminals and body ground Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR