Inspection Procedure

HINT:

In case of using the hand-held tester, start the inspection step  1 and in case of not using the hand-held tester, start from step  2.

1. READ VALUE OF HAND-HELD TESTER 
   1. Connect the hand-held tester to the DLC3.
   2. Check the cooler (room temp. sensor) thermistor using DATA LIST.

   Result: 

   COOLER (ROOM TEMP. SENSOR) DATA LIST
   
   

   A	NG
   B	OK (Checking from the PROBLEM SYMPTOMS TABLE )
   C	OK (Checking from the DTC)

   1. B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  
   2. C: Go to step   6 
   3. A: GO TO NEXT STEP 
2. INSPECT AIR CONDITIONING AMPLIFIER (TR - SG-5) 
   1. Remove an A/C amplifier with connectors being connected.
   2. Turn the ignition switch to the "ON" position.
   3. Measure the voltage between terminals TR and SG-5 of A/C amplifier connector at each temperature.

      Standard: 

      • 1.8 to 2.2 V at 25°C (77°F) 
      • 1.2 to 1.6 V at 40°C (104°F) 
   Fig 1: Measuring Voltage Between Terminals TR & SG-5 Amplifier Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   HINT:

   As the temperature increases, the voltage decreases.

   Result: 

   AIR CONDITIONING AMPLIFIER (TR - SG-5)
   
   

   A	NG
   B	OK (Checking from the PROBLEM SYMPTOMS TABLE )
   C	OK (Checking from the DTC)

   1. B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  
   2. C: Go to step   6 
   3. A: GO TO NEXT STEP 
3. INSPECT COOLER (ROOM TEMP. SENSOR) THERMISTOR 
   1. Remove the cooler (room temp. sensor) thermistor.
   2. Measure the resistance according to the value(s) in COOLER (ROOM TEMP. SENSOR) THERMISTOR  .
   COOLER (ROOM TEMP. SENSOR) THERMISTOR
   
   

   Tester connection	Condition	Specified condition
   A13-1 - A13-2	10°C (50°F)	3.00 to 3.73 kΩ
   A13-1 - A13-2	15°C (59°F)	2.45 to 2.88 kΩ
   A13-1 - A13-2	20°C (68°F)	1.95 to 2.30 kΩ
   A13-1 - A13-2	25°C (77°F)	1.60 to 1.80 kΩ
   A13-1 - A13-2	30°C (86°F)	1.28 to 1.47 kΩ
   A13-1 - A13-2	35°C (95°F)	1.00 to 1.22 kΩ
   A13-1 - A13-2	40°C (104°F)	0.80 to 1.00 kΩ
   A13-1 - A13-2	45°C (113°F)	0.65 to 0.85 kΩ
   A13-1 - A13-2	50°C (122°F)	0.50 to 0.70 kΩ
   A13-1 - A13-2	55°C (131°F)	0.44 to 0.60 kΩ
   A13-1 - A13-2	60°C (140°F)	0.36 to 0.50 kΩ

   Fig 2: Measuring Resistance Between Cooler (Room Temp. Sensor)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   NOTE:

   • Even slightly touching the sensor may change the resistance value. Be sure to hold the connector of the sensor.
   • When measuring the sensor temperature, it must be the same as the ambient temperature.

   HINT:

   As the temperature increases, the resistance decreases (see the graph in Fig 3).

   Fig 3: Resistance To Temperature Graph

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG: REPLACE COOLER (ROOM TEMP. SENSOR THERMISTOR) 
   2. OK: GO TO NEXT STEP 
4. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - COOLER (ROOM TEMP. SENSOR) THERMISTOR) 
   1. Check for an open or short circuit in harness and connector between terminal TR of A/C amplifier and cooler (room temp. sensor) thermistor (See ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).
   1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
   2. OK: GO TO NEXT STEP 
5. CHECK HARNESS AND CONNECTOR (COOLER (ROOM TEMP. SENSOR) THERMISTOR - AIR CONDITIONING AMPLIFIER) 
   1. Check for an open or short circuit in harness and connector between cooler (room temp. sensor) thermistor and terminal SG-5 of A/C amplifier (See ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).
   1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
   2. OK: GO TO NEXT STEP 
6. READ OUTPUT DTC 
   1. Clear the DTCs.
   2. Read the DTC at least 8.5 minutes after turning the ignition switch to the "ON" position.

      Standard: Normal codes are output. 

   1. NG: REPLACE AIR CONDITIONING AMPLIFIER 
   2. OK: USE SIMULATION METHOD TO CHECK