HEATING / AIR CONDITIONING AIR CONDITIONING SYSTEM(for Gasoline Model) B141A15 Room Temperature Sensor Circuit Short to Battery or Open
DESCRIPTION
The room temp. sensor (cooler 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 room temp. sensor (cooler 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 to the room temp. sensor (cooler thermistor) and reads voltage changes due to changes in the resistance of the room temp. sensor (cooler thermistor).
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Memory | DTC Output from | Priority |
|---|---|---|---|---|---|---|
| B141A15 | Room Temperature Sensor Circuit Short to Battery or Open | Diagnosis Condition:
Ignition switch ON Malfunction: Open or short (+B) in room temperature sensor circuit Detection Time: Continuously for 4 seconds or more |
·
Room temp. sensor (cooler thermistor) ·
Harness or connector ·
Air conditioning amplifier assembly |
Memorized | Air Conditioner | A |
| Vehicle Condition | |||
|---|---|---|---|
| Pattern 1 | Pattern 2 | ||
| Diagnosis Condition | Ignition switch ON | ○ | ○ |
| Malfunction | Open in room temperature sensor circuit | ○ | - |
| Short (+B) in room temperature sensor circuit | - | ○ | |
| Detection Time | Continuously for 4 seconds or more | Continuously for 4 seconds or more | |
| Trip Count | 1 trip | 1 trip | |
- HINT:
-
If the conditions of either of these patterns are detected, a DTC will be stored.
WIRING DIAGRAM
PROCEDURE
Pre-procedure1
| *a | Front view of wire harness connector
(to Room Temp. Sensor (Cooler Thermistor)) |
Disconnect the E57 room temp. sensor (cooler thermistor) connector.
Procedure1
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
Tester Connection Condition Specified Condition Click Location & Routing(E57)Location & Routingewd_type=routing;type=c;code=E57
Click Connector(E57)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>Cooler Thermistor (Room Temperature Sensor)ewd_type=component;type=c;code=E57;pinno=1
E57-1 (+) - Body ground Ignition switch ON 0 to 5.5 V
- Result:
Proceed to OK NG
Post-procedure1
None
OK
NG
Clear the DTCs.
- Body Electrical > Air Conditioner > Clear DTCs
- 50002 450
- Result:
Proceed to NEXT
NEXT
Pre-procedure1
Turn the ignition switch off.
| *a | Front view of wire harness connector
(to Room Temp. Sensor (Cooler Thermistor)) |
Disconnect the E57 room temp. sensor (cooler thermistor) connector.
| *1 | Room Temp. Sensor (Cooler Thermistor) |
| *2 | Air Conditioning Amplifier Assembly |
Connect terminals 1 and 2 of the room temp. sensor (cooler thermistor) connector on the wire harness side.
Turn the ignition switch to ON and wait for 4 seconds or more.
Procedure1
Check for DTCs.
- Body Electrical > Air Conditioner > Trouble Codes
- 50001 450
- Result:
Result Proceed to B141A11 is output A B141A15 is output B
Post-procedure1
None
A
B
Pre-procedure1
Disconnect the E57 room temp. sensor (cooler thermistor) connector.
Disconnect the E45 air conditioning amplifier assembly connector.
Procedure1
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition Click Location & Routing(E57,E45)Location & Routingewd_type=routing;type=c,c;code=E57,E45
Click Connector(E57)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>Cooler Thermistor (Room Temperature Sensor)ewd_type=component;type=c;code=E57;pinno=1,2
Click Connector(E45)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>Air Conditioning Amplifier Assemblyewd_type=component;type=c;code=E45;pinno=5,3
E57-1 - E45-5 (TR) Always Below 1 Ω E57-2 - E45-3 (SG-1) Always Below 1 Ω
- Result:
Proceed to OK NG
Post-procedure1
None
OK
NG
Pre-procedure1
Disconnect the E57 room temp. sensor (cooler thermistor) connector.
Disconnect the E45 air conditioning amplifier assembly connector.
Procedure1
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition Click Location & Routing(E57,E45)Location & Routingewd_type=routing;type=c,c;code=E57,E45
Click Connector(E57)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>Cooler Thermistor (Room Temperature Sensor)ewd_type=component;type=c;code=E57;pinno=1
Click Connector(E45)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>Air Conditioning Amplifier Assemblyewd_type=component;type=c;code=E45;pinno=5
E57-1 or E45-5 (TR) - Other terminals and body ground Always 10 kΩ or higher
- Result:
Proceed to OK NG
Post-procedure1
None
OK
NG