- Front room temperature sensor
- Harness or connector between room temperature sensor and air conditioning amplifier assembly
- Air conditioning amplifier assembly
| Last Modified: 11-27-2007 | 1.6 C | |
| Service Category: Vehicle Interior | Section: Heating/Air Conditioning | |
| Model Year: 2008 | Model: LX570 | Doc ID: RM000002LJ300AX |
| Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DESCRIPTION (2008 LX570) | ||
|
DTC |
B1411/11 |
Room Temperature Sensor Circuit |
DESCRIPTION
The front 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 front room temperature sensor and reads voltage changes as the resistance of the front 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 front room temperature sensor circuit. |
|
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
|
1. |
READ VALUE USING TECHSTREAM (FRONT ROOM TEMPERATURE SENSOR) |
(a) Use the Data List to check if the front room temperature sensor is functioning properly.
Air Conditioner
|
Tester Display |
Measurement Item/Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|
|
Room Temperature Sensor |
Front 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: -19°C (-2.2°F). Short in the circuit: 70°C (158°F). |
OK:
The display is as specified in the normal condition.
|
|
2. |
INSPECT FRONT ROOM TEMPERATURE SENSOR |
|
(a) Remove the front room temperature sensor
|
(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 |
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).
|
|
3. |
CHECK HARNESS AND CONNECTOR (ROOM TEMPERATURE SENSOR - AIR CONDITIONING AMPLIFIER) |
(a) Disconnect the E32 sensor connector.
(b) Disconnect the E35 amplifier connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
E32-1 (+) - E35-9 (TR) |
Always |
Below 1 Ω |
|
E32-2 (-) - E35-32 (SG-1) |
||
|
E35-9 (TR) - Body ground |
Always |
0.4 to 8.0 kΩ |
|
E35-32 (SG-1) - Body ground |
Always |
Below 1 Ω |
|
|
|