Inspection Procedure

WARNING: This page is about a different car, the 2004 Toyota Camry Solara. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT A/C ROOM TEMPERATURE SENSOR (COOLER (ROOM TEMP. SENSOR) THERMISTOR)

Remove the A/C room temperature sensor (cooler (room temp. sensor) thermistor).

Measure the resistance according to the value(s) in A/C ROOM TEMPERATURE SENSOR RESISTANCE .

Standard:

A/C ROOM TEMPERATURE SENSOR RESISTANCE

Tester connection	Condition	Specified condition
A12-1 - A12-2	10°C (50°F)	3.00 to 3.73 kΩ
A12-1 - A12-2	15°C (59°F)	2.45 to 2.88 kΩ
A12-1 - A12-2	20°C (68°F)	1.95 to 2.30 kΩ
A12-1 - A12-2	25°C (77°F)	1.60 to 1.80 kΩ
A12-1 - A12-2	30°C (86°F)	1.28 to 1.47 kΩ
A12-1 - A12-2	35°C (95°F)	1.00 to 1.22 kΩ
A12-1 - A12-2	40°C (104°F)	0.80 to 1.00 kΩ
A12-1 - A12-2	45°C (113°F)	0.65 to 0.85 kΩ
A12-1 - A12-2	50°C (122°F)	0.50 to 0.70 kΩ
A12-1 - A12-2	55°C (131°F)	0.44 to 0.60 kΩ
A12-1 - A12-2	60°C (140°F)	0.36 to 0.50 kΩ

Fig 1: Identifying Terminals Of A/C Room Temperature Sensor Connector

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 must be the same as the ambient temperature.

HINT:

As the temperature increases, the resistance decreases (see Fig 2 ).

Fig 2: Temperature Resistance Graph

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE A/C ROOM TEMPERATURE SENSOR (COOLER (ROOM TEMP SENSOR) THERMISTOR)
OK: Go to Next Step.

INSPECT AIR CONDITIONING AMPLIFIER (TR - SG-5)

Remove the A/C amplifier with connector still connected.
Turn the ignition switch to the ON position.

Measure the voltage according to the value(s) in AIR CONDITIONING AMPLIFIER (TR - SG-5) VOLTAGE .

Standard:

AIR CONDITIONING AMPLIFIER (TR - SG-5) VOLTAGE

Tester connection	Condition	Specified condition
A11-24 (TR) - A11-22 (SG-5)	Ignition switch ON at 25°C (77°F)	1.8 to 2.2 V
A11-24 (TR) - A11-22 (SG-5)	Ignition switch ON at 40°C (104°F)	1.2 to 1.6 V

Fig 3: Air Conditioning Amplifier Connector Wire Harness View

HINT:

As the temperature increases, the voltage decreases.

AIR CONDITIONING AMPLIFIER (TR - SG-5) CHECK RESULT

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

B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (SEE TERMINALS OF ECU )
C: REPLACE AIR CONDITIONING AMPLIFIER (SEE OVERHAUL )
A: Go to Next Step.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - A/C ROOM TEMPERATURE SENSOR (COOLER (ROOM TEMP SENSOR) THERMISTOR)) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE )
1. Measure the resistance according to the value(s) in Fig 4 .
  Standard:
  
  Fig 4: Air Conditioning Amplifier - A/C Room Temperature Sensor Resistance Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 5: Checking Air Conditioning Amplifier - A/C Room Temperature Sensor Resistance
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
2. OK: REPLACE AIR CONDITIONING AMPLIFIER (SEE OVERHAUL )