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

1. -

DTC detecting condition:

Immediately at fault recognition

Trouble symptom:

Engine stall
Failure of engine to start

Wiring diagram:

Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

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

Yes : Go to 2 .

No : Repair the following item.
- Open circuit or short circuit to ground in harness between M/B and exhaust camshaft position sensor LH connector
- Poor contact of coupling connector
- Blown out of fuse
CHECK HARNESS BETWEEN ECM AND EXHAUST CAMSHAFT POSITION SENSOR LH CONNECTOR (OPEN) .
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Measure the resistance between ECM connector and exhaust camshaft position sensor LH connector.
  Connector and terminal
  
  (E158) No. 51 - (E65) No. 3:
  
  (E158) No. 64 - (E65) No. 2:
Is the resistance less than 1 Ω?

Yes : Go to 3 .

No : Repair the open circuit in the harness between ECM connector and exhaust camshaft position sensor LH connector.
CHECK HARNESS BETWEEN ECM AND EXHAUST CAMSHAFT POSITION SENSOR LH CONNECTOR (SHORT TO GROUND) .
Measure the resistance between exhaust camshaft position sensor LH connector and engine ground.

Connector and terminal

(E65) No. 2 - Engine ground:

Is the resistance 1 MΩ or more?

Yes : Go to 4 .

No : Repair the short circuit to ground in harness between ECM connector and exhaust camshaft position sensor LH connector.
CHECK HARNESS BETWEEN ECM AND EXHAUST CAMSHAFT POSITION SENSOR LH CONNECTOR (SHORT TO POWER SUPPLY) .
Measure the voltage between exhaust camshaft position sensor LH connector and engine ground.

Connector and terminal

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

Is the voltage 5 V or more?

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

No : Go to 5 .
CHECK EXHAUST CAMSHAFT POSITION SENSOR LH STATUS .
Check the installation condition of the exhaust camshaft position sensor LH.

Is the mounting bolt of the exhaust camshaft position sensor LH tightened securely?

Yes : Go to 6 .

No : Securely tighten the mounting bolt of the exhaust camshaft position sensor LH. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>CAMSHAFT POSITION SENSOR>INSTALLATION .
CHECK EXHAUST CAMSHAFT POSITION SENSOR LH .
Check the waveform of the exhaust camshaft position sensor LH. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>CONTROL MODULE I/O SIGNAL .

Is there any abnormality in waveform?

Yes : Replace the exhaust camshaft position sensor LH. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>CAMSHAFT POSITION SENSOR .

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