DESCRIPTION
The cooler (room temp. sensor) thermistor is installed in the instrument panel to detect the cabin temperature, which is used to control the air conditioning system. The resistance of the cooler (room temp. sensor) thermistor 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 assembly applies voltage (5 V) to the cooler (room temp. sensor) thermistor and reads voltage changes due to changes in the resistance of the cooler (room temp. sensor) thermistor.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Memory |
---|---|---|---|---|
B1411/11 | Room Temperature Sensor Circuit | Open or short in room temperature sensor circuit |
| Memorized (4 sec. or more)* |
HINT:
If the cabin temperature is approximately -18.6°C (-1.48°F) or lower, DTC B1411/11 may be output even though the system is normal.
WIRING DIAGRAM
PROCEDURE
1. | READ VALUE USING TECHSTREAM |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Air Conditioner / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Air Conditioner > Data List Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
---|---|---|---|---|
Room Temperature Sensor | Cooler (room temp. sensor) thermistor | Min.: -6.50°C (20.30°F) Max.: 57.25°C (135.05°F) | Actual cabin temperature displayed | - |
Tester Display |
---|
Room Temperature Sensor |
OK:
The display is as specified in the normal condition column.
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 | ![]() | REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
|
2. | INSPECT COOLER (ROOM TEMP. SENSOR) THERMISTOR |
(a) Remove the cooler (room temp. sensor) thermistor. Click here |
|
(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:
HINT:
As the temperature increases, the resistance decreases (see the graph).
NG | ![]() | REPLACE COOLER (ROOM TEMP. SENSOR) THERMISTOR |
|
3. | CHECK HARNESS AND CONNECTOR (COOLER (ROOM TEMP. SENSOR) THERMISTOR - AIR CONDITIONING AMPLIFIER ASSEMBLY) |
(a) Disconnect the J42 air conditioning amplifier assembly connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
J42-14 (TR) - J16-1 | Always | Below 1 Ω |
J42-1 (SG-1) - J16-2 | Always | Below 1 Ω |
J42-14 (TR) or J16-1 - Body ground | Always | 10 kΩ or higher |
J42-1 (SG-1) or J16-2 - Body ground | Always | 10 kΩ or higher |
OK | ![]() | REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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