- Room temperature sensor
- Harness or connector between room temperature sensor and air conditioning amplifier
- Air conditioning amplifier
| Last Modified: 04-05-2023 | 6.11:8.1.0 | Doc ID: RM100000000ZXI8 |
| Model Year Start: 2017 | Model: Sienna | Prod Date Range: [08/2016 - ] |
| Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1411/11; Room Temperature Sensor Circuit; 2017 - 2020 MY Sienna [08/2016 - ] | ||
|
DTC |
B1411/11 |
Room Temperature Sensor Circuit |
DESCRIPTION
The room temperature sensor is installed in the instrument panel. It detects the cabin temperature to control the air conditioning AUTO mode. The resistance of the room temperature sensor changes in accordance with the cabin temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.
The air conditioning amplifier 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 appropriate signals to the air conditioning amplifier.
|
DTC Code |
DTC Detection condition |
Trouble Area |
|---|---|---|
|
B1411/11 |
Open or short in room temperature sensor circuit |
|
WIRING DIAGRAM
PROCEDURE
|
1. |
READ VALUE USING TECHSTREAM |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Air Conditioner / Data List.
(e) Check the value(s) by referring to the table below.
Air Conditioner
|
Tester Display |
Measurement Item/Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|
|
Room Temperature Sensor |
Room temperature sensor / Min.: -6.5°C (20.3°F) Max.: 57.25°C (135.05°F) |
Actual cabin temperature displayed |
- |
OK:
The display is as specified in the Normal Condition column.
Result
|
Result |
Proceed to |
|---|---|
|
NG |
A |
|
OK (When troubleshooting according to Problem Symptoms Table) |
B |
|
OK (When troubleshooting according to the DTC) |
C |
| B |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
| C |
|
|
|
2. |
INSPECT ROOM TEMPERATURE SENSOR |
(a) Remove the room temperature sensor.
(b) Disconnect the room temperature sensor connector.
(c) 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:
- Hold the sensor only by its connector. Touching the sensor may change the resistance value.
- When measuring, the sensor temperature must be the same as the ambient temperature.
HINT:
As the temperature increases, the resistance decreases (see the graph).
Text in Illustration
|
*a |
Component without harness connected (Room Temperature Sensor) |
|
*b |
Sensing Portion |
| NG |
|
|
|
3. |
CHECK HARNESS AND CONNECTOR (ROOM TEMPERATURE SENSOR - AIR CONDITIONING AMPLIFIER) |
(a) Disconnect the D75 air conditioning amplifier connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
D75-29 (TR) - D34-1 |
Always |
Below 1 Ω |
|
D75-34 (SG-4) - D34-2 |
Always |
Below 1 Ω |
|
D75-29 (TR) - Body ground |
Always |
10 kΩ or higher |
|
D75-34 (SG-4) - Body ground |
Always |
10 kΩ or higher |
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|