AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System), Diagnostic DTC:B1411/11
| DTC Code | DTC Name |
|---|---|
| B1411/11 | Room Temperature Sensor Circuit |
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 a 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)*1 |
*1: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.
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
READ VALUE USING GTS
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Body Electrical / Air Conditioner / Data List.
Check the value(s) by referring to the table below.
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
-
Body Electrical > Air Conditioner > Data List
Tester Display
Room Temperature Sensor
OK
The display is as specified in the normal condition column.
Result
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
INSPECT COOLER (ROOM TEMP. SENSOR) THERMISTOR
-
*a
Component without harness connected
(Cooler (Room Temp. Sensor) Thermistor)
*b
Sensing Portion
*c
Resistance (kΩ)
*d
Temperature (°C (°F))
*e
Allowable Range
Remove the cooler (room temp. sensor) thermistor.
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
1 - 2
15°C (59°F)
2.45 to 2.88 kΩ
1 - 2
20°C (68°F)
1.95 to 2.30 kΩ
1 - 2
25°C (77°F)
1.60 to 1.80 kΩ
1 - 2
30°C (86°F)
1.28 to 1.47 kΩ
1 - 2
35°C (95°F)
1.00 to 1.22 kΩ
1 - 2
40°C (104°F)
0.80 to 1.00 kΩ
1 - 2
45°C (113°F)
0.65 to 0.85 kΩ
1 - 2
50°C (122°F)
0.50 to 0.70 kΩ
1 - 2
55°C (131°F)
0.44 to 0.60 kΩ
1 - 2
60°C (140°F)
0.36 to 0.50 kΩ
Note:Hold the sensor only by its connector. Touching the sensing portion may change the resistance value.
When measuring, the sensor temperature must be the same as the ambient temperature.
Tip:As the temperature increases, the resistance decreases (see the graph).
Result
Proceed to
OK
NG
-
CHECK HARNESS AND CONNECTOR (COOLER (ROOM TEMP. SENSOR) THERMISTOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)
Disconnect the E28 air conditioning amplifier assembly connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
E28-29 (TR) - E15-1
Always
Below 1 Ω
E28-34 (SG-1) - E15-2
Always
Below 1 Ω
E28-29 (TR) - Body ground
Always
10 kΩ or higher
E28-34 (SG-1) - Body ground
Always
10 kΩ or higher
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR