DTC B1507 External Air Temperature Open/Short-Circuit Detection

DTC DETECTING CONDITION:

Open or short circuit in ambient sensor

TROUBLE SYMPTOM:

WIRING DIAGRAM:

Air conditioning system <Ref. to WIRING DIAGRAM , Air Conditioning System.>

Fig 1: External Air Temperature Open/Short-Circuit Detection Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

Step	Check	Yes	No
1 CHECK DTC. Read the DTC of the combination meter using the Subaru Select Monitor. <Ref. to READ DIAGNOSTIC TROUBLE CODE (DTC) .>	Is DTC B1507 displayed? (Current malfunction)	Go to step 2.	Go to step 6.
2 CHECK CURRENT DATA. Using the Subaru Select Monitor, display the «Ambient air temperature» from {Data monitor}. <Ref. to READ CURRENT DATA .>	Is data displayed?	System is normal.	Go to step 3.
3 CHECK HARNESS. Turn the ignition switch to OFF. Disconnect the combination meter connector and ambient sensor connector. Using the tester, measure the resistance between terminals. Connector & terminal (i10) No. 36 - (F78) No. 2: (i10) No. 27 - (F78) No. 1:	Is the resistance 10 Ω or less?	Go to step 4.	Repair the open circuit of harness or replace harness.
4 CHECK HARNESS. Using the tester, measure the resistance between terminals. Connector & terminal (i10) No. 36 - Chassis ground: (i10) No. 27 - Chassis ground:	Is the resistance 10 Ω or less?	Repair the short circuit of harness or replace harness.	Go to step 5.
5 CHECK AMBIENT SENSOR. Perform the inspection of ambient sensor unit. <Ref. to INSPECTION , Ambient Sensor.>	Is the check result OK?	Go to step 6.	Replace the sensor.
6 CHECK CONNECTOR. Turn the ignition switch to OFF. Disconnect connectors.	Is there poor contact of connector?	Repair or replace the poor contact of connector.	A temporary change of voltage occurred.