LEMON Manuals: Even more car manuals for everyone
Home >> Subaru >> 2013 >> Legacy Premium, Automatic CVT Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 26 (Engine Controls (Diagnostics) (H4DO)) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P219A Bank 1 Air-Fuel Ratio Imbalance >> Wiring Diagram

DTC P219A Bank 1 Air-Fuel Ratio Imbalance: Wiring Diagram

WARNING: This page is about a different car, the 2013 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.

Engine electrical system, non-turbo model < Refer to appropriate SYSTEM WIRING DIAGRAM. >

Fig 1: Oxygen Sensor - Wiring Diagram (1 Of 2)
G08570425Courtesy of SUBARU OF AMERICA, INC.
Fig 2: Oxygen Sensor - Wiring Diagram (2 Of 2)
G08570428Courtesy of SUBARU OF AMERICA, INC.
Fig 3: Fuel Injector - Wiring Diagram
G08570423Courtesy of SUBARU OF AMERICA, INC.
DIAGNOSTIC PROCEDURE

Step Check Yes No
1 CHECK FRONT OXYGEN (A/F) SENSOR CONNECTOR AND COUPLING CONNECTOR.  Has water entered the connector? Completely remove any water inside. Go to step 2  .
2 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connectors from ECM and front oxygen (A/F) sensor.
  3. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector.

    Connector & terminal 

    (B136) No. 19 - (E23) No. 3: 

    (B136) No. 18 - (E23) No. 4: 

 Is the resistance less than 1 Ω? Go to step 3  . Repair the harness and connector.
NOTE: In this case, repair the following item:
  • Open circuit in harness between ECM and front oxygen (A/F) sensor connector
  • Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. 
Measure the resistance between ECM and chassis ground.
Connector & terminal 
(B136) No. 19 - Chassis ground: 
(B136) No. 18 - Chassis ground: 		 Is the resistance 1 MΩ or more? Go to step 4  . Repair the ground short circuit of harness between ECM and front oxygen (A/F) sensor connector.
4 CHECK OUTPUT SIGNAL FOR ECM. 
  1. Connect the connector to ECM.
  2. Turn the ignition switch to ON.
  3. Measure the voltage between front oxygen (A/F) sensor connector and chassis ground.

    Connector & terminal 

    (E23) No. 3 (+) - Chassis ground (-): 

 Is the voltage 4.5 V or more? Go to step 6  . Go to step 5  .
5 CHECK OUTPUT SIGNAL FOR ECM. 
Measure the voltage between front oxygen (A/F) sensor connector and chassis ground.
Connector & terminal 
(E23) No. 4 (+) - Chassis ground (-): 		 Is the voltage 4.95 V or more? Go to step 6  . Go to step 7  .
6 CHECK OUTPUT SIGNAL FOR ECM. 
Measure the voltage between front oxygen (A/F) sensor connector and chassis ground.
Connector & terminal 
(E23) No. 3 (+) - Chassis ground (-): 
(E23) No. 4 (+) - Chassis ground (-): 		 Is the voltage 8 V or more? Repair the short circuit to power in the harness between ECM and front oxygen (A/F) sensor connector. After repair, replace the ECM. < Refer to ENGINE CONTROL MODULE (ECM) . > Repair the poor contact of ECM connector.
7 CHECK EXHAUST SYSTEM.  Are there holes or loose bolts on exhaust system? Repair the exhaust system. Go to step 8  .
8 CHECK AIR INTAKE SYSTEM.  Are there holes, loose bolts or disconnection of hose on air intake system? Repair the air intake system. Go to step 9  .
9 CHECK FUEL PRESSURE. 
WARNING: Place "NO OPEN FLAMES" signs near the working area.
CAUTION: Be careful not to spill fuel.

  1. Connect the front oxygen (A/F) sensor connector.
  2. Measure the fuel pressure. < Refer to INSPECTION , Fuel Pressure. >
CAUTION: Release fuel pressure before removing the fuel pressure gauge.
 Is the measured value 340 - 400 kPa (3.5 - 4.1 kg/cm2 , 49 - 58 psi)? Go to step 10  . Repair the following item.
Fuel pressure is too high:
  • Clogged fuel line or bent hose

    Fuel pressure is too low:

  • Improper fuel pump discharge
  • Clogged fuel line
10 CHECK ENGINE COOLANT TEMPERATURE SENSOR. 
  1. Start the engine and warm up completely.
  2. Read the value of «Coolant Temp.» using the Subaru Select Monitor or a general scan tool.
NOTE:
  • Subaru Select Monitor

    For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". < Refer to SUBARU SELECT MONITOR . >

  • General scan tool

    For detailed operation procedures, refer to the general scan tool operation manual.

 Is the value of «Coolant Temp.» 75°C (167°F) or more? Go to step 11  . Replace the engine coolant temperature sensor. < Refer to ENGINE COOLANT TEMPERATURE SENSOR . >
11 CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. 
  1. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F).
  2. For AT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position.
  3. Turn the A/C switch to OFF.
  4. Turn all the accessory switches to OFF.
  5. Read the value of «Mass Air Flow» using the Subaru Select Monitor or a general scan tool.
NOTE:
  • Subaru Select Monitor

    For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". < Refer to SUBARU SELECT MONITOR . >

  • General scan tool

    For detailed operation procedures, refer to the general scan tool operation manual.

 Is the value of «Mass Air Flow» 2.0 - 5.0 g/s (0.26 - 0.66 lb/m)? Go to step 12  . Replace the mass air flow and intake air temperature sensor. < Refer to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR . >
12 CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. 
  1. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F).
  2. For AT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position.
  3. Turn the A/C switch to OFF.
  4. Turn all the accessory switches to OFF.
  5. Open the front hood.
  6. Measure the ambient temperature.
  7. Read the value of «Intake Air Temp.» using the Subaru Select Monitor or a general scan tool.
NOTE:
  • Subaru Select Monitor

    For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". < Refer to SUBARU SELECT MONITOR . >

  • General scan tool

    For detailed operation procedures, refer to the general scan tool operation manual.

 Subtract ambient temperature from «Intake Air Temp.». Is the obtained value -10 - 50°C (-18 - 90°F)? Go to step 13  . Check the mass air flow and intake air temperature sensor. < Refer to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR . >
13 CHECK REAR OXYGEN SENSOR DATA. 
  1. Warm up the engine until engine coolant temperature is higher than 75°C (167°F), and keep the engine speed at 3, 000 rpm. (2 minutes maximum)
  2. Read the value of «Rear O2 Sensor» using the Subaru Select Monitor or a general scan tool.
NOTE:
  • Depress the clutch pedal. (MT model)
  • Subaru Select Monitor

    For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". < Refer to SUBARU SELECT MONITOR . >

  • General scan tool

    For detailed operation procedures, refer to the general scan tool operation manual.

 Is the value of «Rear O2 Sensor » 0.490 V or more? Go to step 14  . Go to step 15  .
14 CHECK REAR OXYGEN SENSOR DATA. 
  1. Warm up the engine until engine coolant temperature is higher than 75°C (167°F), and rapidly reduce the engine speed from 3, 000 rpm.
  2. Read the value of «Rear O2 Sensor» using the Subaru Select Monitor or a general scan tool.
NOTE:
  • Depress the clutch pedal. (MT model)
  • Subaru Select Monitor

    For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". < Refer to SUBARU SELECT MONITOR . >

  • General scan tool

    For detailed operation procedures, refer to the general scan tool operation manual.

 Is the value of «Rear O2 Sensor » 0.250 V or less? Go to step 16  . Go to step 15  .
15 CHECK REAR OXYGEN SENSOR CONNECTOR AND COUPLING CONNECTOR.  Has water entered the connector? Completely remove any water inside. Go to step 17  .
16 CHECK FRONT OXYGEN (A/F) SENSOR USING REAR OXYGEN SENSOR SIGNAL. 
  1. Warm up the engine until engine coolant temperature is higher than 75°C (167°F), then keep the engine idling for 5 minutes or more.
  2. Read the value of «Rear O2 Sensor» using the Subaru Select Monitor or a general scan tool.
NOTE:
  • Subaru Select Monitor

    For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". < Refer to SUBARU SELECT MONITOR . >

  • General scan tool

    For detailed operation procedures, refer to the general scan tool operation manual.

 Is the value in «Rear O2 Sensor » kept at 0.250 V or less for 5 minutes or more? Replace the front oxygen (A/F) sensor. < Refer to FRONT OXYGEN (A/F) SENSOR . > Go to step 17  .
17 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from ECM and rear oxygen sensor.
  3. Measure the resistance of harness between ECM and rear oxygen sensor connector.

    Connector & terminal 

    (B136) No. 20 - (E22) No. 3: 

    (B135) No. 30 - (E22) No. 4: 

 Is the resistance less than 1 Ω? Go to step 18  . Repair the harness and connector.
NOTE: In this case, repair the following item:
  • Open circuit in harness between ECM and rear oxygen sensor connector
  • Poor contact of coupling connector
18 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. 
  1. Connect the connector to ECM.
  2. Turn the ignition switch to ON.
  3. Measure the voltage between rear oxygen sensor connector and chassis ground.

    Connector & terminal 

    (E22) No. 3 (+) - Chassis ground (-): 

 Is the voltage 0.2 - 0.5 V? Replace the rear oxygen sensor. < Refer to FRONT OXYGEN (A/F) SENSOR . > Go to step 19  .
19 CHECK OUTPUT SIGNAL OF ECM. 
  1. Turn the ignition switch to ON.
  2. Measure the voltage between ECM and chassis ground on faulty cylinders.

    Connector & terminal 

    #1 (B134) No. 10 (+) - Chassis ground (-): 

    #2 (B134) No. 11 (+) - Chassis ground (-): 

    #3 (B134) No. 12 (+) - Chassis ground (-): 

    #4 (B134) No. 13 (+) - Chassis ground (-): 

 Is the voltage 10 V or more? Go to step 24  . Go to step 20  .
20 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from fuel injector on faulty cylinders.
  3. Measure the resistance between fuel injector connector and engine ground on faulty cylinders.

    Connector & terminal 

    #1 (E5) No. 1 - Engine ground: 

    #2 (E16) No. 1 - Engine ground: 

    #3 (E6) No. 1 - Engine ground: 

    #4 (E17) No. 1 - Engine ground: 

 Is the resistance 1 MΩ or more? Go to step 21  . Repair the short circuit to ground in harness between ECM and fuel injector connector.
21 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. 
Measure the resistance of harness between ECM and fuel injector connector on faulty cylinders.
Connector & terminal 
#1 (B134) No. 10 - (E5) No. 1: 
#2 (B134) No. 11 - (E16) No. 1: 
#3 (B134) No. 12 - (E6) No. 1: 
#4 (B134) No. 13 - (E17) No. 1: 		 Is the resistance less than 1 Ω? Go to step 22  . Repair the harness and connector.
NOTE: In this case, repair the following item:
  • Open circuit in harness between ECM and fuel injector connector
  • Poor contact of coupling connector
22 CHECK FUEL INJECTOR. 
Measure the resistance between fuel injector terminals on faulty cylinder.
Terminals 
No. 1 - No. 2: 		 Is the resistance 5 - 20 Ω? Go to step 23  . Replace the faulty fuel injector. < Refer to FUEL INJECTOR . >
23 CHECK POWER SUPPLY LINE. 
  1. Turn the ignition switch to ON.
  2. Measure the voltage between fuel injector connector of faulty cylinders and engine ground.

    Connector & terminal 

    #1 (E5) No. 2 (+) - Engine ground (-): 

    #2 (E16) No. 2 (+) - Engine ground (-): 

    #3 (E6) No. 2 (+) - Engine ground (-): 

    #4 (E17) No. 2 (+) - Engine ground (-): 

 Is the voltage 10 V or more? Repair the poor contact of all connectors in fuel injector circuit. Repair the harness and connector.
NOTE: In this case, repair the following item:
  • Open circuit in harness between the main relay and fuel injector connector on faulty cylinders
  • Poor contact of coupling connector
  • Poor contact of main relay connector
24 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from fuel injector on faulty cylinders.
  3. Turn the ignition switch to ON.
  4. Measure the voltage between ECM and chassis ground on faulty cylinders.

    Connector & terminal 

    #1 (B134) No. 10 (+) - Chassis ground (-): 

    #2 (B134) No. 11 (+) - Chassis ground (-): 

    #3 (B134) No. 12 (+) - Chassis ground (-): 

    #4 (B134) No. 13 (+) - Chassis ground (-): 

 Is the voltage 10 V or more? Repair the short circuit to power in harness between ECM and fuel injector connector. Go to step 25  .
25 CHECK FUEL INJECTOR. 
  1. Turn the ignition switch to OFF.
  2. Measure the resistance between fuel injector terminals on faulty cylinder.

    Terminals 

    No. 1 - No. 2: 

 Is the resistance 5 - 20 Ω? Go to step 26  . Replace the faulty fuel injector. < Refer to FUEL INJECTOR . >
26 CHECK INSTALLATION CONDITION OF CAMSHAFT POSITION SENSOR/CRANKSHAFT POSITION SENSOR.  Is the camshaft position sensor or crankshaft position sensor loosely installed? Tighten the camshaft position sensor or crankshaft position sensor. < Refer to INSTALLATION , Camshaft Position Sensor. > < Refer to INSTALLATION , Crankshaft Position Sensor. > Go to step 27  .
27 CHECK CRANKSHAFT POSITION SENSOR PLATE.  Is the crankshaft position sensor plate rusted or does it have broken teeth? Replace the crankshaft position sensor plate. < Refer to CYLINDER BLOCK . > Go to step 28  .
28 CHECK INSTALLATION CONDITION OF TIMING CHAIN. 
Turn the crankshaft using ST, and align the alignment mark on crank sprocket with alignment mark on cylinder block.
ST 18252AA000 CRANKSHAFT SOCKET		 Is the timing chain dislocated from its proper position? Correct the installation condition of timing chain. < Refer to TIMING CHAIN ASSEMBLY . > Go to step 29  .
29 CHECK FUEL LEVEL.  Is the fuel meter indication higher than the "Lower" level? Go to step 30  . Refill the fuel so that the fuel meter indication is higher than the "Lower" level, and proceed to the next step. Go to step 30  .
30 CHECK STATUS OF MALFUNCTION INDICATOR LIGHT. 
  1. Clear the memory using the Subaru Select Monitor or general scan tool. < Refer to CLEAR MEMORY MODE . >
  2. Start the engine, and drive the vehicle 10 minutes or more.
 Does the malfunction indicator light illuminate or blink? Go to step 32  . Go to step 31  .
31 CHECK CAUSE OF MISFIRE. Was the cause of misfire identified when the engine is running? Finish diagnostics operation, if the engine has no abnormality. Repair the poor contact of connector.
NOTE: In this case, repair the following item:
  • Poor contact of ignition coil connector
  • Poor contact of fuel injector connector on faulty cylinders
  • Poor contact of ECM connector
  • Poor contact of coupling connector
32 CHECK AIR INTAKE SYSTEM.  Is there any fault in air intake system? Repair the air intake system.
NOTE: Check the following items.
  • Are there air leaks or air suction caused by loose or dislocated nuts and bolts?
  • Are there cracks or any disconnection of hoses?
 Go to step 33  .
33 CHECK MISFIRE SYMPTOM. 
  1. Turn the ignition switch to ON.
  2. Check for DTC. < Refer to READ DIAGNOSTIC TROUBLE CODE (DTC) . >
 Does the Subaru Select Monitor or general scan tool indicate only one DTC? Go to step 36  . Go to step 34  .
34 CHECK DTC.  Is DTC P0301 and P0303 displayed on the Subaru Select Monitor or general scan tool? Go to step 37  . Go to step 35  .
35 CHECK DTC.  Is DTC P0302 and P0304 displayed on the Subaru Select Monitor or general scan tool? Go to step 38  . Go to step 39  .
36 ONLY ONE CYLINDER.  Is there any fault in the cylinder? Repair or replace faulty parts.
NOTE: Check the following items.
  • Spark plug
  • Ignition coil
  • Fuel injector
  • Compression ratio
 Go to DTC P0171. < Refer to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >
37 GROUP OF #1 AND #3 CYLINDERS.  Are there any faults in #1 and #3 cylinders? Repair or replace faulty parts.
NOTE: Check the following items.
  • Spark plug
  • Ignition coil
  • Fuel injector
  • Compression ratio
  • Skipping timing belt teeth
 Go to DTC P0171. < Refer to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >
38 GROUP OF #2 AND #4 CYLINDERS.  Are there any faults in #2 and #4 cylinders? Repair or replace faulty parts.
NOTE: Check the following items.
  • Spark plug
  • Ignition coil
  • Fuel injector
  • Compression ratio
  • Skipping timing belt teeth
 Go to DTC P0171. < Refer to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >
39 CYLINDER AT RANDOM.  Is the engine idle rough? Go to DTC P0171. < Refer to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC). > Repair or replace faulty parts.
NOTE: Check the following items.
  • Spark plug
  • Ignition coil
  • Fuel injector
  • Compression ratio
scientia non olet · About LEMON Manuals