DESCRIPTION
The cooler thermistor (room temperature sensor) for the front seat is installed in the instrument panel to detect the room temperature and control the heater and air conditioner auto mode. The resistance of the room temperature sensor changes in accordance with the front room temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.
The air conditioning amplifier assembly applies voltage (5 V) to the room temperature sensor and reads voltage changes as the resistance of the room temperature sensor changes. This sensor also sends the appropriate signals to the air conditioning amplifier assembly.
DTC Code |
DTC Detection Condition |
Trouble Area |
---|---|---|
B1411/11 |
An open or short in the cooler thermistor (room temperature sensor) circuit. |
|
WIRING DIAGRAM
PROCEDURE
1. |
READ VALUE USING TECHSTREAM (ROOM TEMPERATURE SENSOR) |
(a) Use the Data List to check if the cooler thermistor (room temperature sensor) is functioning properly (See page ).
Tester Display |
Measurement Item/Range |
Normal Condition |
Diagnostic Note |
---|---|---|---|
Room Temperature Sensor |
Cooler thermistor (room temperature sensor) / Min.: -6.5°C (20.3°F) Max.: 57.25°C (135.05°F) |
Actual room temperature for front seat displayed |
Open in the circuit: -6.5°C (20.3°F). Short in the circuit: 57.25°C (135.05°F). |
OK:
The display is as specified in the normal condition column.
Result
Result |
Proceed to |
---|---|
OK (When troubleshooting according to problem symptoms table) |
A |
OK (When troubleshooting according to the DTC) |
B |
NG |
C |
A |
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
B |
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
|
2. |
INSPECT COOLER THERMISTOR (ROOM TEMPERATURE SENSOR) |
(a) Remove the cooler thermistor (room temperature sensor) (See page ).
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
1 - 2 |
10°C (50°F) |
3.00 to 3.73 kΩ |
15°C (59°F) |
2.45 to 2.88 kΩ |
|
20°C (68°F) |
1.95 to 2.30 kΩ |
|
25°C (77°F) |
1.60 to 1.80 kΩ |
|
30°C (86°F) |
1.28 to 1.47 kΩ |
|
35°C (95°F) |
1.00 to 1.22 kΩ |
|
40°C (104°F) |
0.80 to 1.00 kΩ |
|
45°C (113°F) |
0.65 to 0.85 kΩ |
|
50°C (122°F) |
0.50 to 0.70 kΩ |
|
55°C (131°F) |
0.44 to 0.60 kΩ |
|
60°C (140°F) |
0.36 to 0.50 kΩ |
*a |
Sensing Portion |
*b |
Resistance |
*c |
Allowable Range |
*d |
Temperature |
NOTICE:
HINT:
As the temperature increases, the resistance decreases (refer to the graph).
NG |
REPLACE COOLER THERMISTOR (ROOM TEMPERATURE SENSOR) |
|
3. |
CHECK HARNESS AND CONNECTOR (ROOM TEMPERATURE SENSOR - AIR CONDITIONING AMPLIFIER) |
(a) Disconnect the F26 sensor connector.
(b) Disconnect the F42 amplifier connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
F26-1 - F42-29 (TR) |
Always |
Below 1 Ω |
F26-2 - F42-34 (SG-1) |
||
F42-29 (TR) - Body ground |
Always |
10 kΩ or higher |
F42-34 (SG-1) - Body ground |
OK |
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
IG Power Source Circuit
DESCRIPTION
The main power source is supplied to the air conditioning amplifier assembly
when the ignition switch is turned to ON. The power source is used for operating
the air conditioning amplifier assembly, servo motors, etc.
WIRING DIAGRAM
CAUTIO ...
Diagnosis System
DIAGNOSIS SYSTEM
1. DESCRIPTION
(a) When troubleshooting a vehicle with a diagnosis system, connect the Techstream
to the DLC3 of the vehicle and read various data output from the steering lock actuator
assembly (steering lock ECU).
The steering lock ac ...