Toyota Tundra. Manual — part 2397

Fig. 33: Temperature And Resistance Graph
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

b. Measure the resistance according to the value(s) in the table below.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection Condition Specified Condition

1 -2

10°C (50°F) 3.00 to 3.73 kohms
15°C (59°F) 2.45 to 2.88 kohms
20°C (68°F) 1.95 to 2.30 kohms
25°C (77°F) 1.60 to 1.80 kohms
30°C (86°F) 1.28 to 1.47 kohms
35°C (95°F) 1.00 to 1.22 kohms

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra

HINT:

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

NG: REPLACE AMBIENT TEMPERATURE SENSOR (See REMOVAL )

OK: Go to Next Step

3. CHECK HARNESS AND CONNECTOR (AMBIENT TEMPERATURE SENSOR - AIR

CONDITIONING AMPLIFIER)

a. Disconnect the A15 sensor connector.

b. Disconnect the J19 air conditioning amplifier connector.

40°C (104°F) 0.80 to 1.00 kohms
45°C (113°F) 0.65 to 0.85 kohms
50°C (122°F) 0.50 to 0.70 kohms
55°C (131°F) 0.44 to 0.60 kohms
60°C (140°F) 0.36 to 0.50 kohms

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.

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra

Fig. 34: Identifying Terminals Of J19 Air Conditioning Amplifier Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

c. Measure the resistance according to the value(s) in the table below.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE AIR CONDITIONING AMPLIFIER (See REMOVAL )

DTC B1413/13 EVAPORATOR TEMPERATURE SENSOR CIRCUIT

DESCRIPTION

Tester Connection

Condition Specified Condition

A15-1 - J19-5 (TAM)

Always

Below 1 ohms

A15-2 - J19-13 (SG-2)

A15-1 or J19-5 (TAM) - Body ground

Always

10 kohms or higher

A15-2 or J19-13 (SG-2) - Body ground

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra

The No. 1 cooler thermistor (evaporator temperature sensor) is installed on the evaporator in the air conditioner
unit to detect the cooled air temperature that has passed through the evaporator and control the air conditioning.
It sends appropriate signals to the air conditioning amplifier. The resistance of the No. 1 cooler thermistor
(evaporator temperature sensor) changes in accordance with the cooled air temperature that has passed through
the evaporator. As the temperature decreases, the resistance increases. As the temperature increases, the
resistance decreases.

The air conditioning amplifier applies voltage (5 V) to the No. 1 cooler thermistor (evaporator temperature
sensor) and reads voltage changes as the resistance of the No. 1 cooler thermistor (evaporator temperature
sensor) changes. This sensor is used for frost prevention.

DTC DETECTION CONDITION CHART

WIRING DIAGRAM

Fig. 35: Evaporator Temperature Sensor - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

1. READ VALUE USING TECHSTREAM (EVAPORATOR FIN THERMISTOR)

a. Use the Data List to check if the evaporator fin thermistor is functioning properly.

Air Conditioner

DTC

DTC Detection Condition

Trouble Area

B1413/13

Open or short in evaporator
temperature sensor circuit



No. 1 cooler thermistor
(evaporator temperature
sensor)



Air conditioning harness



Air conditioning amplifier

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra