DTC B1411/11: Room Temperature Sensor Circuit: Procedure

1. Connect Techstream to the DLC3.
2. Turn the ignition switch on (IG) and turn Techstream on.
3. Select the item below in the Data List, and read the display on Techstream.
   DATA LIST / AIR CONDITIONER:
   
   

   Item	Measure Item / Display (Range)	Normal Condition	Diagnostic Note
   Room Temperature Sensor	Room temperature sensor / min.: -6.5°C (20.3°F) max.: 57.25°C (135.05°F)	Actual cabin temperature is displayed	-

   OK

   The display is as specified in the normal condition.

   Result

   Result	Proceed to
   NG	A
   OK (Checking from the PROBLEM SYMPTOM TABLE)	B
   OK (Checking from the DTC)	C

B → PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE 

C → REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY 

A: Go to next step 

1. Remove the A/C amplifier with connectors still connected.
   Fig 1: Identifying Air Conditioning Amplifier (TR - SG-1) Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the ignition switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   D37-16 (TR) - D37-19 (SG-1)	Ignition switch on (IG) at 25°C (77°F)	1.8 to 2.2 V
   D37-16 (TR) - D37-19 (SG-1)	Ignition switch on (IG) at 40°C (104°F)	1.2 to 1.6 V

   HINT: 

   As the temperature increases, the voltage decreases.

   Result

   Result	Proceed to
   NG	A
   OK (Checking from the PROBLEM SYMPTOM TABLE)	B
   OK (Checking from the DTC)	C

B → PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE 

C → REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY 

A: Go to next step 

1. Remove the A/C room temperature sensor.
   Fig 2: Identifying A/C Room Temperature Sensor (D34) Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.
   Fig 3: Identifying Resistance & Temperature Graph

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D34-1 - D34-2	10°C (50°F)	3.00 to 3.73 kΩ
   D34-1 - D34-2	15°C (59°F)	2.45 to 2.88 kΩ
   D34-1 - D34-2	20°C (68°F)	1.95 to 2.30 kΩ
   D34-1 - D34-2	25°C (77°F)	1.60 to 1.80 kΩ
   D34-1 - D34-2	30°C (86°F)	1.28 to 1.47 kΩ
   D34-1 - D34-2	35°C (95°F)	1.00 to 1.22 kΩ
   D34-1 - D34-2	40°C (104°F)	0.80 to 1.00 kΩ
   D34-1 - D34-2	45°C (113°F)	0.65 to 0.85 kΩ
   D34-1 - D34-2	50°C (122°F)	0.50 to 0.70 kΩ
   D34-1 - D34-2	55°C (131°F)	0.44 to 0.60 kΩ
   D34-1 - D34-2	60°C (140°F)	0.36 to 0.50 kΩ

   NOTE:

   • Only hold the sensor at its connector. Touching the sensor may change the resistance value.
   • When measuring, the sensor temperature must be the same as the ambient temperature.

   HINT: 

   As the temperature increases, the resistance decreases (See  Fig.6 the graph).

NG → REPLACE A/C ROOM TEMPERATURE SENSOR 

OK: Go to next step 

1. Disconnect the connector from A/C room temperature sensor.
   Fig 4: Identifying D34 A/C Room Temperature Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the connector from A/C amplifier.
   Fig 5: Identifying A/C Amplifier Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D37-16 (TR) - D34-1	Always	Below 1 Ω
   D37-19 (SG-1) - D34-2	Always	Below 1 Ω
   D37-16 (TR) - Body ground	Always	10 kΩ or higher
   D37-19 (SG-1) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY