Check Ambient Temperature Meter System Communication Circuit

DIAGNOSTIC PROCEDURE

Step	Check	Yes	No
1 CHECK AMBIENT SENSOR POWER SUPPLY. Disconnect the ambient sensor connector. Turn the ignition switch to ON. Measure the voltage between the ambient sensor connector and chassis ground. Connector & terminal (F78) No. 1 (+) - Chassis ground (-):	Is the voltage 4 V or more?	Go to step 2.	Check the harness for open or short between the fuse and MFD.
2 CHECK HARNESS BETWEEN AMBIENT SENSOR AND COMBINATION METER ASSEMBLY. Disconnect the connector of combination meter assembly. Check harness between ambient sensor and combination meter assembly. Connector & terminal (F78) No. 1 - (i10) No. 27: (F78) No. 2 - (i10) No. 36:	Is harness normal?	Go to step 3.	Repair or replace the harness.
3 CHECK AMBIENT SENSOR. Check the ambient sensor. < Ref. to INSPECTION , Ambient Sensor. >	Is the ambient sensor operating properly?	Go to step 4.	Replace the ambient sensor.
4 CHECK AMBIENT TEMPERATURE DISPLAY. Connect the combination meter assembly connector. Install the 3 kΩ resistance between connector terminals of the ambient sensor. Turn the ignition switch to ON. Connector & terminal (F78) No. 1 - No. 2:	Does the ambient temperature display 25°C (77°F)?	Repair the poor contact between the ambient sensor and harness connector.	Go to step 5.
5 CHECK CURRENT DATA. Using the Subaru Select Monitor, display the data of «Ambient Air Temperature». NOTE: For detailed operation procedures, refer to "Application help".	Is the ambient temperature of 25°C (77°F) output?	Go to step 6.	Replace the meter - main assembly. < Ref. to COMBINATION METER . >
6 CHECK MFD. Remove the MFD. Attach the ambient temperature display to another vehicle on which the ambient temperature display operates normally to check its operation.	Does the ambient temperature display 25°C (77°F)?	Replace the MFD.	Replace the meter - main assembly. < Ref. to COMBINATION METER . >