DTC P1261: Cylinder 1 Direct Fuel Injector Circuit/Open: Notes

DTC detecting condition:

Immediately at fault recognition

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 .

Wiring diagram:

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

Courtesy of SUBARU OF AMERICA, INC.

CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR (FOR CYLINDER DIRECT INJECTION) CONNECTOR (OPEN) .
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Measure the resistance between ECM terminals on faulty fuel injectors (for cylinder direct injection).
  Connector & terminal
  
  #2 (E53) No. 86 - (E53) No. 95:
  
  #3 (E53) No. 84 - (E53) No. 93:
  
  #4 (E53) No. 85 - (E53) No. 94:
Is the resistance 1.74 - 2.04 Ω (at 20°C (68°F))?

Yes: Go to 2.

No: Repair the open circuit of the harness between the ECM connector and fuel injector (for cylinder direct injection) connector.
CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR (FOR CYLINDER DIRECT INJECTION) CONNECTOR (SHORT TO GROUND) .
Measure the resistance between ECM and engine ground on faulty fuel injectors (for cylinder direct injection).

Connector & terminal

#1 (E53) No. 87 - Engine ground:

#1 (E53) No. 96 - Engine ground:

#2 (E53) No. 86 - Engine ground:

#2 (E53) No. 95 - Engine ground:

#3 (E53) No. 84 - Engine ground:

#3 (E53) No. 93 - Engine ground:

#4 (E53) No. 85 - Engine ground:

#4 (E53) No. 94 - Engine ground:

Is the resistance 1 MΩ or more?

Yes: Go to 3.

No: Repair the short circuit to ground in the harness between ECM connector and fuel injector (for cylinder direct injection) connector.
CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR (FOR CYLINDER DIRECT INJECTION) CONNECTOR (SHORT TO POWER SUPPLY) .
1. Turn the ignition switch to ON.
2. Measure the voltage between ECM connector and engine ground on faulty fuel injectors (for cylinder direct injection).
  Connector & terminal
  
  #1 (E53) No. 87 (+) - Engine ground (-):
  
  #1 (E53) No. 96 (+) - Engine ground (-):
  
  #2 (E53) No. 86 (+) - Engine ground (-):
  
  #2 (E53) No. 95 (+) - Engine ground (-):
  
  #3 (E53) No. 84 (+) - Engine ground (-):
  
  #3 (E53) No. 93 (+) - Engine ground (-):
  
  #4 (E53) No. 85 (+) - Engine ground (-):
  
  #4 (E53) No. 94 (+) - Engine ground (-):
Is the voltage 1 V or more?

Yes: Repair the short circuit to power in harness between ECM connector and fuel injector (for cylinder direct injection) connectors.

No: Go to 4.
CHECK FUEL INJECTOR (FOR CYLINDER DIRECT INJECTION) .
Check the fuel injector (for cylinder direct injection) on faulty cylinders. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>FUEL INJECTOR>INSPECTION .

Is the check result OK?

Yes: Go to 5.

No: Replace the faulty fuel injector (for cylinder direct injection). Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>FUEL INJECTOR .
CHECK FOR POOR CONTACT .
Check for poor contact of ECM connector.

Is there poor contact of ECM connector?

Yes: Repair the poor contact of ECM connector.

No: Replace the ECM. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>ENGINE CONTROL MODULE (ECM) .