DTC B1417/17: Rear Evaporator Temperature Sensor Circuit: Procedure

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

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Ambient Temp Sensor(Rear)	Rear evaporator temperature sensor / Min.: -29.7°C (-21.46°F) Max.: 59.55°C (139.19°F)	Actual rear evaporator temperature is displayed	Open circuit: -29.7°C (-21.46°F) Short circuit: 59.55°C (139.19°F)

   OK

   The display is as specified in the normal condition column.

   Result

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

B → See step   4 

C → See step   5 

A: Go to next step 

1. Remove the rear air conditioning harness.
   Fig 1: Identifying Evaporator Temperature Sensor Resistance & Temperature Graph With Connector End View

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

   Standard resistance

   Tester Connection	Condition	Specified Condition
   N12-7 (-) - N12-8 (+)	-10°C (14°F)	7.30 to 9.10 kΩ
   N12-7 (-) - N12-8 (+)	-5°C (23°F)	5.65 to 6.95 kΩ
   N12-7 (-) - N12-8 (+)	0°C (32°F)	4.40 to 5.35 kΩ
   N12-7 (-) - N12-8 (+)	5°C (41°F)	3.40 to 4.15 kΩ
   N12-7 (-) - N12-8 (+)	10°C (50°F)	2.70 to 3.25 kΩ
   N12-7 (-) - N12-8 (+)	15°C (59°F)	2.14 to 2.58 kΩ
   N12-7 (-) - N12-8 (+)	20°C (68°F)	1.71 to 2.05 kΩ
   N12-7 (-) - N12-8 (+)	25°C (77°F)	1.38 to 1.64 kΩ
   N12-7 (-) - N12-8 (+)	30°C (86°F)	1.11 to 1.32 kΩ

   NOTE:

   • Touching the thermistor even slightly may change the resistance value. Be sure to hold the connector of the thermistor.
   • When measuring, the thermistor temperature must be the same as the ambient temperature.

   HINT: 

   As the temperature increases, the resistance decreases (see the graph in illustration above).

NG → REPLACE REAR AIR CONDITIONING HARNESS 

OK: Go to next step 

1. Disconnect the N12 rear air conditioning harness connector.
   Fig 2: Checking Harness And Connector (Rear Air Conditioning Harness - Air Conditioning Amplifier)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the D38 amplifier connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   N12-8 (+) - D38-4 (TEC)	Always	Below 1 Ω
   N12-7 (-) - D38-19 (SGND)	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   6