DTC P0390: Camshaft Position Sensor "B" Circuit Bank 2: Notes

DTC detecting condition:

Immediately at fault recognition

Trouble symptom:

Engine stalls.
Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>Clear Memory Mode>OPERATION , and inspection mode Ref. to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>Inspection Mode>PROCEDURE .

Use the check board when measuring the ECM terminal voltage and resistance.

Wiring diagram:

Engine Electrical System Ref. to WIRING SYSTEM>Engine Electrical System>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

CHECK POWER SUPPLY OF CAMSHAFT POSITION SENSOR .
1. Turn the ignition switch to OFF.
2. Disconnect the connector from camshaft position sensor.
3. Turn the ignition switch to ON.
4. Measure the voltage between camshaft position sensor connector and engine ground.
  Connector & terminal
  
  (E65) No. 1 (+) - Engine ground (-):
Is the voltage 10 V or more?

Yes: Go to 2.

No: Repair the harness and connector.

NOTE: In this case, repair the following item:
- Open circuit or short circuit to ground in harness between main relay connector and camshaft position sensor connector
- Poor contact of coupling connector
CHECK HARNESS BETWEEN ECM AND CAMSHAFT POSITION SENSOR CONNECTOR .
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Measure the resistance between ECM connector and camshaft position sensor connector.
  Connector & terminal
  
  (E158) No. 33 - (E65) No. 2:
  
  (E158) No. 34 - (E65) No. 3:
Is the resistance less than 1 Ω?

Yes: Go to 3.

No: Repair the harness and connector.

NOTE: In this case, repair the following item:
- Open circuit in harness between ECM connector and camshaft position sensor connector
- Poor contact of coupling connector
CHECK HARNESS BETWEEN ECM AND CAMSHAFT POSITION SENSOR CONNECTOR .
Measure the resistance between camshaft position sensor connector and engine ground.

Connector & terminal

(E65) No. 2 - Engine ground:

Is the resistance 1 MΩ or more?

Yes: Go to 4.

No: Repair short circuit to ground in harness between ECM connector and camshaft position sensor connector.
CHECK HARNESS BETWEEN ECM AND CAMSHAFT POSITION SENSOR CONNECTOR .
Measure the voltage between camshaft position sensor connector and engine ground.

Connector & terminal

(E65) No. 2 (+) - Engine ground (-):

Is the voltage 5 V or more?

Yes: Repair the short circuit to power in the harness between ECM connector and camshaft position sensor connector.

No: Go to 5.
CHECK CONDITION OF CAMSHAFT POSITION SENSOR .
Check installation condition of the camshaft position sensor.

Is the camshaft position sensor installation bolt tightened securely?

Yes: Go to 6.

No: Tighten the camshaft position sensor installation bolt securely. Ref. to FUEL INJECTION (FUEL SYSTEMS) (EXCEPT FOR STI)>Camshaft Position Sensor>INSTALLATION .
CHECK CAMSHAFT POSITION SENSOR .
Check the waveform of the camshaft position sensor. Ref. to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>Engine Control Module (ECM) I/O Signal .

Is there any abnormality in waveform?

Yes: Replace the camshaft position sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (EXCEPT FOR STI)>Camshaft Position Sensor .

No: Repair the following item.
- Poor contact of ECM connector
- Poor contact of camshaft position sensor connector
- Poor contact of coupling connector