DTC B1412: Ambient Temperature Sensor Circuit [11/2018 - 02/2019]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Enter the following menus: Body Electrical / Air Conditioner / Data List.
5. 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 system 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 [11/2018 - ] 

Result: 

NG 

See step  2

1. Remove the thermistor assembly.

   Refer to REMOVAL [11/2018 - ]

2. Inspect the thermistor assembly.

   Refer to INSPECTION [11/2018 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE THERMISTOR ASSEMBLY. Refer to  REMOVAL [11/2018 - ] 

Result: 

OK 

See step  3

1. Disconnect the G47 air conditioning amplifier assembly connector.
2. Disconnect the A19 thermistor assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G47-1 (TAM) - A19-2	Always	Below 1 Ω
   G47-14 (SG-2) - A19-1	Always	Below 1 Ω
   G47-1 (TAM) or A19-2 - Other terminals and body ground	Always	10 kΩ or higher
   G47-14 (SG-2) or A19-1 - 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 [11/2018 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR