DTC B1412/12 Ambient Temperature Sensor Circuit
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
1 READ VALUE OF INTELLIGENT TESTER
(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:
OK: The display is as specified in the normal condition column.
Result
2 INSPECT AMBIENT TEMPERATURE SENSOR
(a) Remove the ambient temperature sensor.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
NOTICE:
HINT: As the temperature increases, the resistance decreases (see the graph).
3 CHECK HARNESS AND CONNECTOR (AMBIENT TEMPERATURE SENSOR - A/C AMPLIFIER)
(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
REPLACE A/C AMPLIFIER
Uniform Tire Quality Grading
This information has been prepared in accordance with regulations
issued by the National Highway Traffic Safety Administration of the
U.S. Department of Transportation.
It provides the purchasers and/or prospective purchasers of Toyota
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Diagnosis system
1. DESCRIPTION
When troubleshooting a vehicle with the diagnosis
system, the only difference from the usual
troubleshooting procedure is connecting the intelligent
tester to the vehicle and reading various data output from
the vehicle's clearance warning ECU.
The clearance warning ECU record ...
Precaution
1. PRECAUTION FOR VEHICLE WITH SRS AIRBAG
AND SEAT BELT PRETENSIONER
Some operations in this section may affect SRS
airbag system. Before performing the corresponding
operations, please read the NOTICE of the SRS
airbag for the proper operations.
COMPONENTS
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