2007 TOYOTA SIENNA sensor

AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)AC–29
AC
DESCRIPTION
The ambient temperature sensor is installed in front of the condenser to detect the ambient temperature
which is used to control the air conditioner "AUTO" mode. This sensor is connected to the A/C amplifier
and detects fluctuations in the ambient temperature. This data is used for controlling the cabin
temperature. The sensor sends a signal to the A/C amplifier. The resistance of the ambient temperature
sensor changes in accordance with the ambient temperature. As the temperature decreases, the
resistance increases. As the temperature increases, the resistance decreases.
The A/C amplifier applies voltage (5 V) to the ambient temperature sensor and reads voltage changes as
the resistance of the ambient temperature sensor changes.
WIRING DIAGRAM
INSPECTION PROCEDURE
(a) Connect the intelligent tester to the DLC3.
DTC B1412/12 Ambient Temperature Sensor Circuit
DTC No. DTC Detection Condition Trouble Area
B1412/12 Open or short in ambient temperature sensor circuit• Ambient temperature sensor
• Harness or connector between ambient
temperature sensor and A/C amplifier
• A/C amplifier
1READ VALUE OF INTELLIGENT TESTER
I008282E17

AC–30AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)
AC
(b) Turn the ignition switch to the ON position and turn the
intelligent tester main switch on.
(c) Select the item below in the DATA LIST, and read the
display on the intelligent tester.
DATA LIST / AIR CONDITIONER:
OK:
The display is as specified in the normal condition
column.
Result
B
C
A
Tester Display Measurement Item/Range Normal Condition Diagnostic Note
AMBI TEMP SENS
(Ambient temperature sensor)Ambient temperature sensor /
min: -30.8
C (-23.44F), max:
50.8C (123.44F)Actual ambient temperature is
displayed-
Result Proceed to
NGA
OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B
OK (When troubleshooting according to the DTC) C
PROCEED TO NEXT CIRCUIT INSPECTION
SHOWN IN PROBLEM SYMPTOMS TABLE
REPLACE A/C AMPLIFIER

AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)AC–31
AC
(a) Remove the ambient temperature sensor.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NOTICE:
• 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 the graph).
NG
OK
2INSPECT AMBIENT TEMPERATURE SENSOR
E118395E14
Tester Connection Condition Specified Condition
A1-1 - A1-2 10
C (50F) 3.00 to 3.73 k
A1-1 - A1-2 15C (59F) 2.45 to 2.88 k
A1-1 - A1-2 20C (68F) 1.95 to 2.30 k
A1-1 - A1-2 25C (77F) 1.60 to 1.80 k
A1-1 - A1-2 30C (86F) 1.28 to 1.47 k
A1-1 - A1-2 35C (95F) 1.00 to 1.22 k
A1-1 - A1-2 40C (104F) 0.80 to 1.00 k
A1-1 - A1-2 45C (113F) 0.65 to 0.85 k
A1-1 - A1-2 50C (122F) 0.50 to 0.70 k
A1-1 - A1-2 55C (131F) 0.44 to 0.60 k
A1-1 - A1-2 60C (140F) 0.36 to 0.50 k
REPLACE AMBIENT TEMPERATURE
SENSOR

AC–32AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)
AC
(a) Disconnect the ambient temperature sensor connector.
(b) Disconnect the A/C amplifier connector.
(c) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
3CHECK HARNESS AND CONNECTOR (AMBIENT TEMPERATURE SENSOR - A/C
AMPLIFIER)
E124473E06
E143742E26
Tester Connection Condition Specified Condition
A1-2 - A9-32 (TAM) Always Below 1
A1-1 - A9-24 (SG-6) Always Below 1
A9-32 (TAM) - Body
groundAlways 10 k or higher
A9-24 (SG-6) - Body
groundAlways 10 k
or higher
REPAIR OR REPLACE HARNESS OR
CONNECTOR
REPLACE A/C AMPLIFIER

AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)AC–33
AC
DESCRIPTION
The evaporator temperature sensor (A/C thermistor) is installed on the evaporator in the air conditioning
unit. It detects the temperature of the cooled air that has passed through the evaporator and its signal is
used to control the air conditioning. It sends a signal to the A/C amplifier. The resistance of the evaporator
temperature sensor (A/C thermistor) changes in accordance with the temperature of the cooled air that
has passed through the evaporator. As the temperature decreases, the resistance increases. As the
temperature increases, the resistance decreases.
The A/C amplifier applies voltage (5 V) to the evaporator temperature sensor (A/C thermistor) and reads
voltage changes as the resistance of the evaporator temperature sensor (A/C thermistor) changes. This
sensor is used to prevent the evaporator from freezing.
WIRING DIAGRAM
INSPECTION PROCEDURE
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position and turn the
intelligent tester main switch on.
(c) Select the item below in the DATA LIST, and read the
display on the intelligent tester.
DATA LIST / AIR CONDITIONER:
DTC B1413/13 Evaporator Temperature Sensor Circuit
DTC No. DTC Detection Condition Trouble Area
B1413/13 Open or short in evaporator temperature sensor circuit• Evaporator temperature sensor
• Harness or connector between evaporator
temperature sensor and A/C amplifier
• A/C amplifier
1READ VALUE OF INTELLIGENT TESTER
I035354E03
Tester Display Measurement Item/Range Normal Condition Diagnostic Note
EVAP TEMP
(Evaporator thermistor)Evaporator thermistor / min.: -
29.7
C (-21.46F), max.: 59.55C
(139.19F)Actual evaporator temperature is
displayed-

AC–34AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)
AC
OK:
The display is as specified in the normal condition
column.
Result
B
C
A
(a) Disconnect the connector from the evaporator
temperature sensor.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NOTICE:
• 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 evaporator temperature.
HINT:
As the temperature increases, the resistance decreases
(see the graph).
NG
OK
Result Proceed to
NGA
OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B
OK (When troubleshooting according to the DTC) C
PROCEED TO NEXT CIRCUIT INSPECTION
SHOWN IN PROBLEM SYMPTOMS TABLE
REPLACE A/C AMPLIFIER
2INSPECT EVAPORATOR TEMPERATURE SENSOR
E148014E02
Tester Connection Condition Specified Condition
A12-1 - A12-2 -10
C (14F) 7.30 to 9.10 k
A12-1 - A12-2 -5C (23F) 5.65 to 6.95 k
A12-1 - A12-2 0C (32F) 4.40 to 5.35 k
A12-1 - A12-2 5C (41F) 3.40 to 4.15 k
A12-1 - A12-2 10C (50F) 2.70 to 3.25 k
A12-1 - A12-2 15C (59F) 2.14 to 2.58 k
A12-1 - A12-2 20C (68F) 1.71 to 2.05 k
A12-1 - A12-2 25C (77F) 1.38 to 1.64 k
A12-1 - A12-2 30C (86F) 1.11 to 1.32 k
REPLACE EVAPORATOR TEMPERATURE
SENSOR

AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)AC–35
AC
(a) Disconnect the evaporator temperature sensor
connector.
(b) Disconnect the A/C amplifier connector.
(c) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
3CHECK HARNESS AND CONNECTOR (EVAPORATOR TEMPERATURE SENSOR - A/C
AMPLIFIER)
E124472E09
E143742E34
Tester Connection Condition Specified Condition
A9-34 (TE) - A12-2 Always Below 1
A9-22 (SG-4) - A12-1 Always Below 1
A9-34 (TE) - Body
groundAlways 10 k or higher
A9-22 (SG-4) - Body
groundAlways 10 k
or higher
REPAIR OR REPLACE HARNESS OR
CONNECTOR
REPLACE A/C AMPLIFIER

AC–36AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)
AC
DESCRIPTION
The rear evaporator temperature sensor is installed on the rear evaporator. It detects the rear evaporator
temperature. The sensor sends a signal to the A/C amplifier. The resistance of the rear evaporator
temperature sensor changes in accordance with the rear evaporator temperature. As the temperature
decreases, the resistance increases. As the temperature increases, the resistance decreases.
The A/C amplifier applies voltage (5 V) to the rear evaporator temperature sensor and reads voltage
changes as the resistance of the rear evaporator temperature sensor changes.
WIRING DIAGRAM
INSPECTION PROCEDURE
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position and turn the
intelligent tester main switch on.
DTC B1417/17 Rear Evaporator Temperature Sensor Circuit
DTC No. DTC Detection Condition Trouble Area
B1417/17Open or short in rear evaporator temperature sensor
circuit• Rear evaporator temperature sensor
• Harness or connector between rear evaporator
temperature sensor and A/C amplifier
• A/C amplifier
1READ VALUE OF INTELLIGENT TESTER
I008282E19