B1412

AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1412: Ambient Temperature Sensor Circuit

DTC B1412 - Ambient Temperature Sensor Circuit

DESCRIPTION

The ambient temperature sensor is installed in front of the condenser. This sensor detects the temperature outside the cabin and sends the appropriate signals to the A/C amplifier via the CAN communication system.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM
(a) Use the Techstream to check if the CAN communication system DTC.
Result:






B -- GO TO DTC B1499
A -- Continue to next step.
2. READ VALUE USING TECHSTREAM (AMBIENT TEMPERATURE SENSOR)
(a) Use the Data List to check if the ambient temperature sensor is functioning properly.

Air Conditioner:





OK:
The display is as specified in the normal condition column.
Result:






C -- REPLACE AIR CONDITIONING AMPLIFIER
B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.
3. INSPECT COMBINATION METER




(a) Disconnect the C37 combination meter connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





(c) Reconnect the combination meter connector.
NG -- INSPECT AMBIENT TEMPERATURE SENSOR
OK -- Continue to next step.
4. REPLACE COMBINATION METER
(a) Replace the combination meter Removal.
HINT: Since the combination meter cannot be inspected while it is removed from the vehicle, replace the combination meter with a normal one and check that the condition returns to normal.

NEXT -- Continue to next step.
5. CHECK FOR DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- REPLACE AIR CONDITIONING AMPLIFIER
A -- END
6. INSPECT AMBIENT TEMPERATURE SENSOR




(a) Remove the ambient temperature sensor.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





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).

NG -- REPLACE AMBIENT TEMPERATURE SENSOR
OK -- Continue to next step.
7. CHECK HARNESS AND CONNECTOR (AMBIENT TEMPERATURE SENSOR - COMBINATION METER)




(a) Disconnect the A15 ambient temperature sensor connector.
(b) Disconnect the C37 combination meter connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:





(d) Reconnect the ambient temperature sensor connector.
(e) Reconnect the combination meter connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
8. REPLACE COMBINATION METER
(a) Replace the combination meter Removal.
HINT: Since the combination meter cannot be inspected while it is removed from the vehicle, replace the combination meter with a normal one and check that the condition returns to normal.

NEXT -- Continue to next step.
9. CHECK FOR DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- REPLACE AIR CONDITIONING AMPLIFIER
A -- END