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Engine Controls - Engine (Diagnostics) (H4SO - 2.5L SOHC): Wiring Subaru Outback BR

Testing & Diagnostics 5 illustrations ~735 words

WIRING DIAGRAM

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND COMBINATION METER CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Turn the ignition switch to ON.Does the malfunction indicator light illuminate?Repair the ground short circuit of harness between ECM and combination meter connector.Replace the ECM. Ref. to ENGINE CONTROL MODULE (ECM) .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK STATUS OF MALFUNCTION INDICATOR LIGHT. Turn the ignition switch to OFF. Check the delivery (test) mode fuse is removed. Turn the ignition switch to ON. (engine OFF)Does the malfunction indicator light illuminate?Go to step 2 .Repair the malfunction indicator light circuit. Ref. to MALFUNCTION INDICATOR LIGHT DOES NOT COME ON , Malfunction Indicator Light.
2 CHECK HARNESS BETWEEN ECM AND COMBINATION METER CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Turn the ignition switch to ON.Does the malfunction indicator light illuminate?Repair the ground short circuit of harness between ECM and combination meter connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND DELIVERY (TEST) MODE FUSE. Turn the ignition switch to OFF. Install the delivery (test) mode fuse of the main fuse box. Measure the resistance of harness between ECM connectors. Connector & terminal (B136) No. 34 - (B136) No. 4Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and delivery (test) mode fuse Poor contact of joint connector
4 CHECK FOR POOR CONTACT. Check for poor contact of ECM connector.Is there poor contact of ECM connector?Repair the poor contact of ECM connector.Replace the ECM. Ref. to ENGINE CONTROL MODULE (ECM) .
NOTE
In this case, repair the following item: Open circuit of harness between ECM and delivery (test) mode fuse Poor contact of joint connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK DELIVERY (TEST) MODE FUSE. Check the delivery (test) mode fuse is removed. Turn the ignition switch to ON.Does the malfunction indicator light blink?Go to step 2 .System is normal. NOTE: Malfunction indicator light blinks when delivery (test) mode fuse is connected.
2 CHECK HARNESS BETWEEN ECM AND CHASSIS GROUND. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance of harness between ECM and chassis ground. Connector & terminal (B136) No. 34 - Chassis groundIs the resistance less than 5 ohms?Repair the short circuit to ground in harness between ECM and delivery (test) mode fuse.Replace the ECM. Ref. to ENGINE CONTROL MODULE (ECM) .
NOTE
Malfunction indicator light blinks when delivery (test) mode fuse is connected.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK POWER SUPPLY TO FRONT OXYGEN (A/F) SENSOR. Turn the ignition switch to OFF. Disconnect the connector from front oxygen (A/F) sensor. Turn the ignition switch to ON. Measure the voltage between front oxygen (A/F) sensor connector and engine ground. Connector & terminal (E24) No. 4 (+) - Engine ground (-)Is the voltage 10 V or more?Go to step 2 .Repair the power supply line. NOTE: In this case, repair the following item: Open circuit in harness between A/F, oxygen sensor relay connector and front oxygen (A/F) sensor connector Poor contact of A/F, oxygen sensor relay connector Poor contact of coupling connector Fault of A/F, oxygen sensor relay
2 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM and front oxygen (A/F) sensor connector. Connector & terminal (B136) No. 5 - (E24) No. 3: (B136) No. 6 - (E24) No. 3Is the resistance less than 1 ohms?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 GROUND CIRCUIT FOR ECM. Measure the resistance of harness between ECM and chassis ground. Connector & terminal (B134) No. 3 - Chassis ground: (B134) No. 4 - Chassis ground: (B134) No. 6 - Chassis ground: (B137) No. 1 - Chassis ground: (B137) No. 3 - Chassis groundIs the resistance less than 5 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
4 CHECK FRONT OXYGEN (A/F) SENSOR. Measure the resistance between front oxygen (A/F) sensor connector terminals. Terminals No. 3 - No. 4Is the resistance 2 - 3 ohms?Repair the poor contact of ECM connector.Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .
NOTE
In this case, repair the following item: Open circuit in harness between A/F, oxygen sensor relay connector and front oxygen (A/F) sensor connector Poor contact of A/F, oxygen sensor relay connector Poor contact of coupling connector Fault of A/F, oxygen sensor relay
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
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. Turn the ignition switch to OFF. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 5 (+) - Chassis ground (-): (B136) No. 6 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the short circuit of harness to power supply between ECM and front oxygen (A/F) sensor connector.Go to step 2 .
2 CHECK GROUND CIRCUIT FOR ECM. Disconnect the connector from ECM. Measure the resistance between ECM and chassis ground. Connector & terminal (B134) No. 3 - Chassis ground: (B134) No. 4 - Chassis ground: (B134) No. 6 - Chassis ground: (B137) No. 1 - Chassis ground: (B137) No. 3 - Chassis groundIs the resistance less than 5 ohms?Repair the poor contact of ECM connector.Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Turn the ignition switch to OFF. Measure the voltage between ECM and chassis ground. Connector & terminal (B135) No. 6 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the short circuit of harness to power supply between ECM and rear oxygen sensor connector.Go to step 2 .
2 CHECK GROUND CIRCUIT FOR ECM. Disconnect the connector from ECM. Measure the resistance between ECM and chassis ground. Connector & terminal (B134) No. 3 - Chassis ground: (B134) No. 4 - Chassis ground: (B134) No. 6 - Chassis ground: (B137) No. 1 - Chassis ground: (B137) No. 3 - Chassis groundIs the resistance less than 5 ohms?Repair the poor contact of ECM connector.Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND OIL SWITCHING SOLENOID VALVE RH CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and oil switching solenoid valve RH. Measure the voltage between ECM and chassis ground. Connector & terminal (B134) No. 7 (+) - Chassis ground (-): (B134) No. 15 (+) - Chassis ground (-)Is the voltage less than 1 V?Go to step 2 .Repair the short circuit to power supply in harness between ECM and oil switching solenoid valve RH connector.
2 CHECK HARNESS BETWEEN ECM AND OIL SWITCHING SOLENOID VALVE RH CONNECTOR. Measure the resistance of harness between ECM and oil switching solenoid valve RH connector. Connector & terminal (B134) No. 7 - (E69) No. 1: (B134) No. 15 - (E69) No. 2Is the resistance less than 1 ohms?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and oil switching solenoid valve RH connector Poor contact of coupling connector
3 CHECK OIL SWITCHING SOLENOID VALVE RH. Measure the resistance between oil switching solenoid valve RH terminals. Terminals No. 1 - No. 2Is the resistance 6 - 12 ohms?Repair the poor contact of ECM and oil switching solenoid valve RH connector.Replace the oil switching solenoid valve RH. Ref. to OIL SWITCHING SOLENOID VALVE .
NOTE
In this case, repair the following item: Open circuit in harness between ECM and oil switching solenoid valve RH connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND OIL SWITCHING SOLENOID VALVE LH CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and oil switching solenoid valve LH. Measure the voltage between ECM and chassis ground. Connector & terminal (B134) No. 5 (+) - Chassis ground (-): (B134) No. 14 (+) - Chassis ground (-)Is the voltage less than 1 V?Go to step 2 .Repair the short circuit to power supply in harness between ECM and oil switching solenoid valve LH connector.
2 CHECK HARNESS BETWEEN ECM AND OIL SWITCHING SOLENOID VALVE LH CONNECTOR. Measure the resistance between ECM and oil switching solenoid valve LH connector. Connector & terminal (B134) No. 5 - (E70) No. 1: (B134) No. 14 - (E70) No. 2Is the resistance less than 1 ohms?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and oil switching solenoid valve LH connector Poor contact of coupling connector
3 CHECK OIL SWITCHING SOLENOID VALVE LH. Measure the resistance between oil switching solenoid valve LH terminals. Terminals No. 1 - No. 2Is the resistance 6 - 12 ohms?Repair the poor contact of ECM and oil switching solenoid valve LH connector.Replace the oil switching solenoid valve LH. Ref. to OIL SWITCHING SOLENOID VALVE .
NOTE
In this case, repair the following item: Open circuit in harness between ECM and oil switching solenoid valve LH connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of air flow sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage less than 0.2 V?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK POWER SUPPLY OF MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. Turn the ignition switch to OFF. Disconnect the connector from mass air flow and intake air temperature sensor. Turn the ignition switch to ON. Measure the voltage between mass air flow and intake air temperature sensor connector and engine ground. Connector & terminal (B3) No. 3 (+) - Engine ground (-)Is the voltage 10 V or more?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between main relay and mass air flow and intake air temperature sensor connector. Poor contact of main relay connector
3 CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance of harness between ECM and the mass air flow and intake air temperature sensor connector. Connector & terminal (B136) No. 22 - (B3) No. 5Is the resistance less than 1 ohms?Go to step 4 .Repair the open circuit of harness between the ECM and mass air flow and intake air temperature sensor connector.
4 CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 22 - Chassis groundIs the resistance 1 Mohms or more?Go to step 5 .Repair the ground short circuit of harness between ECM and mass air flow and intake air temperature sensor connector.
5 CHECK FOR POOR CONTACT. Check for poor contact of ECM and mass air flow and intake air temperature sensor connector.Is there poor contact of the ECM or the mass air flow and intake air temperature sensor connector?Repair the poor contact of ECM or mass air flow and intake air temperature sensor connector.Replace the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, repair the following item: Open circuit in harness between main relay and mass air flow and intake air temperature sensor connector. Poor contact of main relay connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of air flow sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 5 V or more?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from mass air flow and intake air temperature sensor. Start the engine. Read the data of airflow sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and mass air flow and intake air temperature sensor connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Measure the resistance of harness between mass air flow and intake air temperature sensor connector and engine ground. Connector & terminal (B3) No. 4 - Engine groundIs the resistance less than 5 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and mass air flow and intake air temperature sensor connector. Poor contact of ECM connector
4 CHECK FOR POOR CONTACT. Check for poor contact of mass air flow and intake air temperature sensor connector.Is there poor contact in the mass air flow and intake air temperature sensor connector?Repair any poor contact of the mass air flow and intake air temperature sensor connector.Replace the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and mass air flow and intake air temperature sensor connector. Poor contact of ECM connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of intake manifold absolute pressure signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value less than 13.3 kPa (100 mmHg, 3.94 inHg)?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK POWER SUPPLY OF MANIFOLD ABSOLUTE PRESSURE SENSOR. Turn the ignition switch to OFF. Disconnect the connector from manifold absolute pressure sensor. Turn the ignition switch to ON. Measure the voltage between manifold absolute pressure sensor connector and engine ground. Connector & terminal (E21) No. 3 (+) - Engine ground (-)Is the voltage 4.5 V or more?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and manifold absolute pressure sensor connector. Poor contact of ECM connector Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance of harness between ECM and manifold absolute pressure sensor connector. Connector & terminal (B137) No. 20 - (E21) No. 1Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and manifold absolute pressure sensor connector. Poor contact of coupling connector
4 CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE SENSOR CONNECTOR. Measure the resistance between ECM and chassis ground. Connector & terminal (B137) No. 20 - Chassis groundIs the resistance 1 Mohms or more?Go to step 5 .Repair ground short circuit of harness between ECM and manifold absolute pressure sensor connector.
5 CHECK FOR POOR CONTACT. Check for poor contact of ECM and manifold absolute pressure sensor connector.Is there poor contact of ECM or manifold absolute pressure sensor connector?Repair the poor contact of ECM or manifold absolute pressure sensor connector.Replace the manifold absolute pressure sensor. Ref. to MANIFOLD ABSOLUTE PRESSURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, repair the following item: Open circuit of harness between ECM and manifold absolute pressure sensor connector. Poor contact of ECM connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and manifold absolute pressure sensor connector. Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of intake manifold absolute pressure signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value 119.5 kPa (896.5 mmHg, 35.29 inHg) or more?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from manifold absolute pressure sensor. Start the engine. Read the data of intake manifold absolute pressure signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value 119.5 kPa (896.5 mmHg, 35.29 inHg) or more?Repair the short circuit of harness to power supply between ECM and manifold absolute pressure sensor connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Measure the resistance of harness between manifold absolute pressure sensor connector and engine ground. Connector & terminal (E21) No. 2 - Engine groundIs the resistance less than 5 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and manifold absolute pressure sensor connector. Poor contact of ECM connector Poor contact of coupling connector
4 CHECK FOR POOR CONTACT. Check for poor contact of manifold absolute pressure sensor connector.Is there poor contact of manifold absolute pressure sensor connector?Repair the poor contact of manifold absolute pressure sensor connector.Replace the manifold absolute pressure sensor. Ref. to MANIFOLD ABSOLUTE PRESSURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit of harness between ECM and manifold absolute pressure sensor connector. Poor contact of ECM connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK ENGINE COOLANT TEMPERATURE. Start the engine and warm up completely. Measure the engine coolant temperature using the Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the temperature 75°C (167°F) or more?Replace the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .Check for DTC P0125. Ref. to DTC P0125 INSUFFICIENT COOLANT TEMPERATURE FOR CLOSED LOOP FUEL CONTROL , Diagnostic Procedure with Diagnostic Trouble Code (DTC).
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of intake air temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the intake air temperature 120°C(248°F) or more?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and mass air flow and intake air temperature sensor. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 31 - Chassis groundIs the resistance 1 Mohms, or more?Replace the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .Repair the ground short circuit of harness between ECM and mass air flow and intake air temperature sensor connector.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of intake air temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the intake air temperature less than -40°C(-40°F)?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK FOR POOR CONTACT. Check for poor contact of ECM and mass air flow and intake air temperature sensor connector.Is there poor contact of the ECM or the mass air flow and intake air temperature sensor connector?Repair the poor contact of ECM or mass air flow and intake air temperature sensor connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and mass airflow and intake air temperature sensor. Measure the resistance of harness between ECM and the mass air flow and intake air temperature sensor connector. Connector & terminal (B136) No. 31 - (B3) No. 1: (B135) No. 30 - (B3) No. 2Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and mass air flow and intake air temperature sensor connector. Poor contact of joint connector
4 CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR. Connect all connectors. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 31 (+) - Chassis ground (-)Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and mass air flow and intake air temperature sensor connector.Replace the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and mass air flow and intake air temperature sensor connector. Poor contact of joint connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of engine coolant temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the engine coolant temperature less than -40°C (-40°F)?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK FOR POOR CONTACT. Check for poor contact of ECM and engine coolant temperature sensor connector.Is there poor contact of ECM or engine coolant temperature sensor connector?Repair the poor contact of ECM or engine coolant temperature sensor connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND ENGINE COOLANT TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and engine coolant temperature sensor. Measure the resistance of harness between ECM and engine coolant temperature sensor connector. Connector & terminal (B137) No. 22 - (E8) No. 2: (B134) No. 29 - (E8) No. 1Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and engine coolant temperature sensor connector Poor contact of coupling connector
4 CHECK HARNESS BETWEEN ECM AND ENGINE COOLANT TEMPERATURE SENSOR CONNECTOR. Connect all connectors. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B137) No. 22 (+) - Chassis ground (-)Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and engine coolant temperature sensor connector.Replace the engine coolant temperature sensor. Ref. to ENGINE COOLANT TEMPERATURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and engine coolant temperature sensor connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and electronic throttle control. Measure the resistance of harness between ECM and electronic throttle control connector. Connector & terminal (B134) No. 18 - (E57) No. 6: (B134) No. 29 - (E57) No. 3Is the resistance less than 1 ohms?Go to step 2 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
2 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 3 - Engine groundIs the resistance less than 5 ohms?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to ON. Measure the voltage between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 6 (+) - Engine ground (-)Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.Go to step 4 .
4 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B134) No. 19 - (B134) No. 18Is the resistance 1 Mohms or more?Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to THROTTLE BODY .Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
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. Turn the ignition switch to OFF. Disconnect the connector from ECM and front oxygen (A/F) sensor connector. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 18 - Chassis ground: (B136) No. 19 - Chassis groundIs the resistance 1 Mohms or more?Go to step 3 .Repair the ground short circuit of harness between ECM and front oxygen (A/F) sensor connector.
3 CHECK FOR POOR CONTACT. Check for poor contact of the front oxygen (A/F) sensor connector.Is there poor contact of front oxygen (A/F) sensor connector?Repair the poor contact of front oxygen (A/F) sensor connector.Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
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. Turn the ignition switch to OFF. Disconnect the connector from front oxygen (A/F) sensor. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 18 (+) - Chassis ground (-): (B136) No. 19 (+) - Chassis ground (-)Is the voltage 8 V or more?Repair the short circuit of harness to power supply between ECM and front oxygen (A/F) sensor connector.Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK EXHAUST SYSTEM. NOTE: Check the following items. Loose installation of front portion of exhaust pipe onto cylinder heads Loose connection between front exhaust pipe and front catalytic converter Damage of exhaust pipe resulting in a holeIs there any fault in exhaust system?Repair the exhaust system.Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .
NOTE
Check the following items. Loose installation of front portion of exhaust pipe onto cylinder heads Loose connection between front exhaust pipe and front catalytic converter Damage of exhaust pipe resulting in a hole

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and front oxygen (A/F) sensor connector. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector. Connector & terminal (B136) No. 18 - (E24) No. 2: (B136) No. 19 - (E24) No. 1Is the resistance less than 1 ohms?Go to step 2 .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
2 CHECK FOR POOR CONTACT. Check for poor contact of ECM and front oxygen (A/F) sensor connector.Is there poor contact of ECM or front oxygen (A/F) sensor connector?Repair the poor contact of ECM or front oxygen (A/F) sensor connector.Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .
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

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK REAR OXYGEN SENSOR DATA. Warm up the engine until engine coolant temperature is above 75°C (167°F), and keep the engine speed at 3,000 RPM. (2 minutes maximum) Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 490 mV or more?Go to step 5 .Go to step 2 .
2 CHECK REAR OXYGEN SENSOR CONNECTOR AND COUPLING CONNECTOR.Has water entered the connector?Completely remove any water inside.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and rear oxygen sensor. Measure the resistance of harness between ECM and rear oxygen sensor connector. Connector & terminal (B136) No. 20 - E250 No. 3: (B134) No. 29 - E250 No. 4Is the resistance less than 1 ohms?Go to step 4 .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
4 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between rear oxygen sensor connector and chassis ground. Connector & terminal E250 No. 3 (+) - Chassis ground (-)Is the voltage 0.2 - 0.5 V?Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .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 rear oxygen sensor connector Poor contact of ECM connector
5 CHECK EXHAUST SYSTEM. Check exhaust system parts. NOTE: Check the following items. Looseness and improper fitting of exhaust system parts Damage (crack, hole etc.) of parts Loose part and improper installation between front oxygen (A/F) sensor and rear oxygen sensorIs there any fault in exhaust system?Repair or replace faulty parts.Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of rear oxygen sensor connector Poor contact of ECM connector
NOTE
Check the following items. Looseness and improper fitting of exhaust system parts Damage (crack, hole etc.) of parts Loose part and improper installation between front oxygen (A/F) sensor and rear oxygen sensor

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK REAR OXYGEN SENSOR DATA. Warm up the engine until engine coolant temperature is above 75°C (167°F), and rapidly reduce the engine speed from 3,000 RPM. Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 250 mV or less?Go to step 5 .Go to step 2 .
2 CHECK REAR OXYGEN SENSOR CONNECTOR AND COUPLING CONNECTOR.Has water entered the connector?Completely remove any water inside.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and rear oxygen sensor. Measure the resistance of harness between ECM and rear oxygen sensor connector. Connector & terminal (B136) No. 20 - E250 No. 3: (B134) No. 29 - E250 No. 4Is the resistance less than 1 ohms?Go to step 4 .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
4 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between rear oxygen sensor connector and chassis ground. Connector & terminal E250 No. 3 (+) - Chassis ground (-)Is the voltage 0.2 - 0.5 V?Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .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 rear oxygen sensor connector Poor contact of ECM connector
5 CHECK EXHAUST SYSTEM. Check exhaust system parts. NOTE: Check the following items. Looseness and improper fitting of exhaust system parts Damage (crack, hole etc.) of parts Loose part and improper installation between front oxygen (A/F) sensor and rear oxygen sensorIs there any fault in exhaust system?Repair or replace faulty parts.Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of rear oxygen sensor connector Poor contact of ECM connector
NOTE
Check the following items. Looseness and improper fitting of exhaust system parts Damage (crack, hole etc.) of parts Loose part and improper installation between front oxygen (A/F) sensor and rear oxygen sensor

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and rear oxygen sensor. Measure the resistance of harness between ECM and rear oxygen sensor connector. Connector & terminal (B136) No. 20 - E250 No. 3Is the resistance less than 1 ohms?Go to step 2 .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
2 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Measure the resistance between rear oxygen sensor connector and chassis ground. Connector & terminal E250 No. 3 - Chassis groundIs the resistance 1 Mohms or more?Go to step 3 .Repair the ground short circuit of harness between ECM and rear oxygen sensor connector.
3 CHECK REAR OXYGEN SENSOR. Measure the resistance between rear oxygen sensor terminals. Terminals No. 3 - No. 4Is the resistance less than 1 ohms?Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of coupling connector
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK REAR OXYGEN SENSOR DATA. Warm up the engine until engine coolant temperature is above 75°C (167°F), and keep the engine speed at 3,000 RPM. (2 minutes maximum) Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 490 mV or more?Go to step 6 .Go to step 2 .
2 CHECK REAR OXYGEN SENSOR DATA. Warm up the engine until engine coolant temperature is above 75°C (167°F), and rapidly reduce the engine speed from 3,000 RPM. Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 250 mV or less?Go to step 6 .Go to step 3 .
3 CHECK REAR OXYGEN SENSOR CONNECTOR AND COUPLING CONNECTOR.Has water entered the connector?Completely remove any water inside.Go to step 4 .
4 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and rear oxygen sensor. Measure the resistance of harness between ECM and rear oxygen sensor connector. Connector & terminal (B136) No. 20 - E250 No. 3: (B134) No. 29 - E250 No. 4Is the resistance less than 1 ohms?Go to step 5 .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
5 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between rear oxygen sensor connector and chassis ground. Connector & terminal E250 No. 3 (+) - Chassis ground (-)Is the voltage 0.2 - 0.5 V?Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .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 rear oxygen sensor connector Poor contact of ECM connector
6 CHECK EXHAUST SYSTEM. Check exhaust system parts. NOTE: Check the following items. Looseness and improper fitting of exhaust system parts Damage (crack, hole etc.) of parts Loose part and improper installation between front oxygen (A/F) sensor and rear oxygen sensorIs there any fault in exhaust system?Repair or replace faulty parts.Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of rear oxygen sensor connector Poor contact of ECM connector
NOTE
Check the following items. Looseness and improper fitting of exhaust system parts Damage (crack, hole etc.) of parts Loose part and improper installation between front oxygen (A/F) sensor and rear oxygen sensor

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of fuel temperature sensor signal using Subaru Select Monitor. NOTE: For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .Is the temperature 120°C (248°F) or higher?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK HARNESS BETWEEN ECM AND FUEL TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and fuel temperature sensor. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 23 - Chassis groundIs the resistance 1 Mohms or more?Replace the fuel temperature sensor. Ref. to FUEL TEMPERATURE SENSOR .Repair the ground short circuit of harness between ECM and fuel pump.
NOTE
For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of fuel temperature sensor signal using Subaru Select Monitor. NOTE: For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .Is the temperature less than -40°C (-40°F)?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK FOR POOR CONTACT. Repair any poor contact between the ECM and fuel temperature sensor connectors.Is there poor contact of the ECM or fuel temperature sensor connectors?Repair any poor contact between the ECM and fuel temperature sensor connectors.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND FUEL TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and fuel temperature sensor. Measure the resistance of the harness between the ECM and fuel temperature sensor connector. Connector & terminal (B136) No. 23 - (R58) No. 2: (B135) No. 30 - (R58) No. 3Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and fuel temperature sensor connector Poor contact of coupling connector Poor contact of joint connector
4 CHECK HARNESS BETWEEN ECM AND FUEL TEMPERATURE SENSOR CONNECTOR. Connect all connectors. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 23 (+) - Chassis ground (-)Is the voltage 5 V or more?Repair the short circuit to power in the harness between the ECM and fuel temperature sensor connector.Replace the fuel temperature sensor. Ref. to FUEL TEMPERATURE SENSOR .
NOTE
For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and fuel temperature sensor connector Poor contact of coupling connector Poor contact of joint connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of oil temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the oil temperature 215°C (419°F) or more?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK HARNESS BETWEEN ECM AND OIL TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and oil temperature sensor. Measure the resistance between ECM and chassis ground. Connector & terminal (B137) No. 21 - Chassis groundIs the resistance 1 Mohms or more?Replace the oil temperature sensor. Ref. to OIL TEMPERATURE SENSOR .Repair the short circuit to ground in harness between ECM and oil temperature sensor connector.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Start the engine. Read the data of oil temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the oil temperature less than -40°C (-40°F)?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK FOR POOR CONTACT. Check for poor contact of ECM and oil temperature sensor connector.Is there poor contact of ECM or oil temperature sensor connector?Repair the poor contact of ECM or oil temperature sensor connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND OIL TEMPERATURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and oil temperature sensor. Measure the resistance of harness between ECM and oil temperature sensor connector. Connector & terminal (B137) No. 21 - (E75) No. 2: (B134) No. 29 - (E75) No. 1Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and oil temperature sensor connector Poor contact of coupling connector
4 CHECK HARNESS BETWEEN ECM AND OIL TEMPERATURE SENSOR CONNECTOR. Connect all connectors. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B137) No. 21 (+) - Chassis ground (-)Is the voltage 5 V or more?Repair the short circuit to power supply in harness between ECM and oil temperature sensor connector.Replace the oil temperature sensor. Ref. to OIL TEMPERATURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and oil temperature sensor connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and electronic throttle control. Measure the resistance between ECM and chassis ground. Connector & terminal (B134) No. 19 - Chassis ground: (B134) No. 28 - Chassis groundIs the resistance 1 Mohms or more?Go to step 2 .Repair the ground short circuit of harness between ECM and electronic throttle control connector.
2 CHECK SHORT CIRCUIT INSIDE THE ECM. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 4 - Engine groundIs the resistance 1 Mohms or more?Replace the electronic throttle control. Ref. to THROTTLE BODY .Repair the ground short circuit of harness between ECM and electronic throttle control connector. Replace the ECM if defective. Ref. to ENGINE CONTROL MODULE (ECM) .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and electronic throttle control. Measure the resistance of harness between ECM and electronic throttle control connector. Connector & terminal (B134) No. 28 - (E57) No. 4: (B134) No. 29 - (E57) No. 3Is the resistance less than 1 ohms?Go to step 2 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
2 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 3 - Engine groundIs the resistance less than 5 ohms?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to ON. Measure the voltage between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 4 (+) - Engine ground (-)Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.Go to step 4 .
4 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B134) No. 19 - (B134) No. 28Is the resistance 1 Mohms or more?Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to THROTTLE BODY .Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK OUTPUT SIGNAL OF ECM. Turn the ignition switch to ON. 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 6 .Go to step 2 .
2 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from fuel injector on faulty cylinders. 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 groundIs the resistance 1 Mohms or more?Go to step 3 .Repair the ground short circuit of harness between ECM and fuel injector connector.
3 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. 1Is the resistance less than 1 ohms?Go to step 4 .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
4 CHECK FUEL INJECTOR. Measure the resistance between fuel injector terminals on faulty cylinder. Terminals No. 1 - No. 2Is the resistance 5 - 20 ohms?Go to step 5 .Replace the faulty fuel injector. Ref. to FUEL INJECTOR .
5 CHECK POWER SUPPLY LINE. Turn the ignition switch to ON. Measure the voltage between fuel injector and engine ground on faulty cylinders. 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 connector and fuel injector connector on faulty cylinders Poor contact of coupling connector Poor contact of main relay connector
6 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from fuel injector on faulty cylinders. Turn the ignition switch to ON. 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 7 .
7 CHECK FUEL INJECTOR. Turn the ignition switch to OFF. Measure the resistance between fuel injector terminals on faulty cylinder. Terminals No. 1 - No. 2Is the resistance 5 - 20 ohms?Replace the faulty fuel injector. Ref. to FUEL INJECTOR .Go to step 8 .
8 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.Go to step 9 .
9 CHECK CRANK SPROCKET. Remove the timing belt cover. Ref. to REMOVAL , Timing Belt Cover.Is the crank sprocket rusted or does it have broken teeth?Replace the crank sprocket. Ref. to CRANK SPROCKET .Go to step 10 .
10 CHECK INSTALLATION CONDITION OF TIMING BELT. Turn the crankshaft using ST, and align the alignment mark on crank sprocket with alignment mark on cylinder block. ST 499987500 CRANKSHAFT SOCKETIs the timing belt dislocated from its proper position?Repair the installation condition of timing belt. Ref. to TIMING BELT .Go to step 11 .
11 CHECK FUEL LEVEL.Is the fuel meter indication higher than the "Lower" level?Go to step 12 .Refill the fuel so that fuel meter indication is higher than the "Lower" level. After replenishing fuel, Go to step 12 .
12 CHECK STATUS OF MALFUNCTION INDICATOR LIGHT. Clear the memory using the Subaru Select Monitor or general scan tool. Ref. to CLEAR MEMORY MODE . Start the engine, and drive the vehicle 10 minutes or more.Does the malfunction indicator light illuminate or blink?Go to step 14 .Go to step 13 .
13 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
14 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 15 .
15 CHECK MISFIRE SYMPTOM. Turn the ignition switch to ON. Read the DTC. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Does the Subaru Select Monitor or general scan tool indicate only one DTC?Go to step 20 .Go to step 16 .
16 CHECK DTC.Is DTC P0301 and P0302 displayed on the Subaru Select Monitor or general scan tool?Go to step 21 .Go to step 17 .
17 CHECK DTC.Is DTC P0303 and P0304 displayed on the Subaru Select Monitor or general scan tool?Go to step 22 .Go to step 18 .
18 CHECK DTC.Is DTC P0301 and P0303 displayed on the Subaru Select Monitor or general scan tool?Go to step 23 .Go to step 19 .
19 CHECK DTC.Is DTC P0302 and P0304 displayed on the Subaru Select Monitor or general scan tool?Go to step 24 .Go to step 25 .
20 ONLY ONE CYLINDER.Is there any fault in the cylinder?Repair or replace faulty parts. NOTE: Check the following items. Sparkplug Spark plug cord Fuel injector Compression ratioGo to DTC P0171. Ref. to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC).
21 GROUP OF #1 AND #2 CYLINDERS.Are there any faults in #1 and #2 cylinders?Repair or replace faulty parts. NOTE: Check the following items. Sparkplug Fuel injector Ignition coil Compression ratio If any fault are not found, check the "IGNITION CONTROL SYSTEM" of #1 and #2 cylinders side. Ref. to IGNITION CONTROL SYSTEM , Diagnostics for Engine Starting Failure.Go to DTC P0171. Ref. to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC).
22 GROUP OF #3 AND #4 CYLINDERS.Are there any faults in #3 and #4 cylinders?Repair or replace faulty parts. NOTE: Check the following items. Sparkplug Fuel injector Ignition coil Compression ratio If any fault are not found, check the "IGNITION CONTROL SYSTEM" of #3 and #4 cylinders side. Ref. to IGNITION CONTROL SYSTEM , Diagnostics for Engine Starting Failure.Go to DTC P0171. Ref. to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC).
23 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. Sparkplug Fuel injector Compression ratio Skipping timing belt teethGo to DTC P0171. Ref. to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC).
24 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. Sparkplug Fuel injector Compression ratio Skipping timing belt teethGo to DTC P0171. Ref. to DTC P0171 SYSTEM TOO LEAN (BANK 1) , Diagnostic Procedure with Diagnostic Trouble Code (DTC).
25 CYLINDER AT RANDOM.Is the engine idle rough?Go to DTC P0171. Ref. 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. Sparkplug Fuel injector Compression ratio
NOTE
In this case, repair the following item: Open circuit in harness between ECM and fuel injector connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit in harness between the main relay connector and fuel injector connector on faulty cylinders Poor contact of coupling connector Poor contact of main relay 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
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?
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Check the following items. Sparkplug Spark plug cord Fuel injector Compression ratio
NOTE
Check the following items. Sparkplug Fuel injector Ignition coil Compression ratio If any fault are not found, check the "IGNITION CONTROL SYSTEM" of #1 and #2 cylinders side. Ref. to IGNITION CONTROL SYSTEM , Diagnostics for Engine Starting Failure.
NOTE
Check the following items. Sparkplug Fuel injector Ignition coil Compression ratio If any fault are not found, check the "IGNITION CONTROL SYSTEM" of #3 and #4 cylinders side. Ref. to IGNITION CONTROL SYSTEM , Diagnostics for Engine Starting Failure.
NOTE
Check the following items. Sparkplug Fuel injector Compression ratio Skipping timing belt teeth
NOTE
Check the following items. Sparkplug Fuel injector Compression ratio Skipping timing belt teeth
NOTE
Check the following items. Sparkplug Fuel injector Compression ratio

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND KNOCK SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B137) No. 2 - (B134) No. 29Is the resistance less than 500 kohms?Go to step 2 .Go to step 3 .
2 CHECK KNOCK SENSOR. Disconnect the connector from knock sensor. Measure the resistance between knock sensor terminals. Terminals No. 1 - No. 2Is the resistance less than 500 kohms?Replace the knock sensor. Ref. to KNOCK SENSOR .Repair the ground short circuit of harness between ECM and knock sensor connector. NOTE: The harness between both connectors are shielded. Remove the shield and repair the short circuit of the harness.
3 CHECK INPUT SIGNAL OF ECM. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B137) No. 2 (+) - Chassis ground (-)Is the voltage 2 V or more?Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.Repair the poor contact of ECM connector.
NOTE
The harness between both connectors are shielded. Remove the shield and repair the short circuit of the harness.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CONDITION OF CRANKSHAFT POSITION SENSOR. Turn the ignition switch to OFF.Is the crankshaft position sensor installation bolt tightened securely?Go to step 2 .Tighten the crankshaft position sensor installation bolt securely. Ref. to CRANKSHAFT POSITION SENSOR .
2 CHECK CRANK SPROCKET. Remove the timing belt cover.Are crank sprocket teeth cracked or damaged?Replace the crank sprocket. Ref. to CRANK SPROCKET .Go to step 3 .
3 CHECK INSTALLATION CONDITION OF TIMING BELT. Turn the crankshaft, and align alignment mark on crank sprocket with alignment mark on cylinder block. ST 499987500 CRANKSHAFT SOCKETIs the timing belt dislocated from its proper position?Repair the installation condition of timing belt. Ref. to TIMING BELT .Replace the crankshaft position sensor. Ref. to CRANKSHAFT POSITION SENSOR .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND CAMSHAFT POSITION SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and camshaft position sensor. Measure the resistance of harness between ECM and camshaft position sensor connector. Connector & terminal (B137) No. 24 - (E15) No. 1: (B137) No. 30 - (E15) No. 2Is the resistance less than 1 ohms?Go to step 2 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and camshaft position sensor connector Poor contact of ECM connector Poor contact of coupling connector
2 CHECK HARNESS BETWEEN ECM AND CAMSHAFT POSITION SENSOR CONNECTOR. Measure the resistance between camshaft position sensor connector and engine ground. Connector & terminal (E15) No. 1 - Engine groundIs the resistance 1 Mohms or more?Go to step 3 .Repair short circuit to ground in harness between ECM and camshaft position sensor connector. NOTE: The harness between both connectors are shielded. Remove the shield and repair the ground short circuit of the harness circuit.
3 CHECK INSTALLATION CONDITION OF CAMSHAFT POSITION SENSOR.Is the camshaft position sensor installation bolt tightened securely?Go to step 4 .Tighten the camshaft position sensor installation bolt securely. Ref. to CAMSHAFT POSITION SENSOR .
4 CHECK CAMSHAFT POSITION SENSOR. Remove the camshaft position sensor. Measure the resistance between terminals of camshaft position sensor connector. Terminals No. 1 - No. 2Is the resistance between 1 and 4kohms?Go to step 5 .Replace the camshaft position sensor. Ref. to CAMSHAFT POSITION SENSOR .
5 CHECK CAM SPROCKET. Remove the timing belt cover. Ref. to TIMING BELT COVER .Are cam sprocket teeth cracked or damaged?Replace the cam sprocket. Ref. to CAM SPROCKET .Go to step 6 .
6 CHECK INSTALLATION CONDITION OF TIMING BELT. Turn the crankshaft using the ST, and align the alignment mark on the cam sprocket with the alignment mark on the timing belt cover LH. ST 499987500 CRANKSHAFT SOCKETIs the timing belt dislocated from its proper position?Repair the installation condition of timing belt. Ref. to TIMING BELT .Replace the camshaft position sensor. Ref. to CAMSHAFT POSITION SENSOR .
NOTE
In this case, repair the following item: Open circuit in harness between ECM and camshaft position sensor connector Poor contact of ECM connector Poor contact of coupling connector
NOTE
The harness between both connectors are shielded. Remove the shield and repair the ground short circuit of the harness circuit.

DIAGNOSTIC PROCEDURE

DIAGNOSTIC PROCEDURE Step Check Yes No 1 CHECK EXHAUST SYSTEM. Check for gas leaks or air suction caused by loose or dislocated nuts and bolts, and open hole at exhaust pipes. NOTE: Check the following positions. Between cylinder head and front exhaust pipe Between front exhaust pipe and front catalytic converter Between front catalytic converter and rear catalytic converter Loose or improperly attached front oxygen (A/F) sensor or rear oxygen sensor Is there any fault in exhaust system? Repair or replace the exhaust system. Ref. to GENERAL DESCRIPTION . Go to step 2 . 2 CHECK WAVEFORM DATA ON THE SUBARU SELECT MONITOR (WHILE DRIVING). Drive at a constant speed of 80 - 112 km/h (50 - 70 MPH). After 5 minutes have elapsed in the condition of step 1 ), use the Subaru Select Monitor while still driving to read the waveform data. At normal condition At abnormal condition (numerous inversion) Is a normal waveform displayed? Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause. Go to step 3 . 3 CHECK WAVEFORM DATA ON THE SUBARU SELECT MONITOR (WHILE IDLING). Run the engine at idle. In the state of step 1 ), read the waveform data using the Subaru Select Monitor. At normal condition At abnormal condition 1 (numerous inversion) At abnormal condition 2 (noise input) Is a normal waveform displayed? Go to step 4 . The waveform is displayed at abnormal condition 1: Go to step 4 . The waveform is displayed at abnormal condition 2: Go to step 5 . 4 CHECK CATALYTIC CONVERTER. Is the catalytic converter damaged? Replace the catalytic converter. Ref. to FRONT CATALYTIC CONVERTER . Go to step 5 . 5 CHECK REAR OXYGEN SENSOR CONNECTOR AND COUPLING CONNECTOR. Has water entered the connector? Completely remove any water inside. Go to step 6 . 6 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and rear oxygen sensor. Measure the resistance of harness between ECM and rear oxygen sensor connector. Connector & terminal (B136) No. 20 - E250 No. 3: (B134) No. 29 - E250 No. 4: Is the resistance less than 1 ohms? Go to step 7 . 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 7 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between rear oxygen sensor connector and chassis ground. Connector & terminal E250 No. 3 (+) - Chassis ground (-): Is the voltage 0.2 - 0.5 V? Go to step 8 . Repair the harness and connector. NOTE: Repair the following locations. Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of ECM and rear oxygen sensor Poor contact of ECM connector 8 CHECK REAR OXYGEN SENSOR SHIELD. Turn the ignition switch to OFF. Expose the rear oxygen sensor connector body side harness sensor shield. Measure the resistance between sensor shield and chassis ground. Is the resistance less than 1 ohms? Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR . Repair the open circuit of rear oxygen sensor harness

Scheme 26

Scheme 26

Scheme 27

Scheme 27

Scheme 28

Scheme 28

Scheme 29

Scheme 29

Scheme 30

Scheme 30
StepCheckYesNo
1 CHECK OUTPUT SIGNAL OF ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B135) No. 4 (+) - Chassis ground (-)Is the voltage 10 V or more?Go to step 2 .Go to step 3 .
2 CHECK FOR POOR CONTACT. Check for poor contact of ECM connector.Is there poor contact of ECM connector?Repair the poor contact of ECM connector.Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary open or short circuit of harness or temporary poor contact of connector may be the cause.
3 CHECK POWER SUPPLY TO DRAIN VALVE. Measure the voltage between drain valve and chassis ground. Connector & terminal (R144) No. 1 (+) - Chassis ground (-)Is the voltage 10 V or more?Go to step 4 .Repair the power supply circuit.
4 CHECK HARNESS BETWEEN ECM AND DRAIN VALVE CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and drain valve. Measure the resistance between the drain valve connector and chassis ground. Connector & terminal (R144) No. 2 - Chassis groundIs the resistance 1 Mohms or more?Go to step 5 .Repair the ground short circuit of harness between ECM and drain valve connector.
5 CHECK HARNESS BETWEEN ECM AND DRAIN VALVE CONNECTOR. Measure the resistance of harness between ECM and drain valve connector. Connector & terminal (B135) No. 4 - (R144) No. 2Is the resistance less than 1 ohms?Go to step 6 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and drain valve connector Poor contact of coupling connector
6 CHECK DRAIN VALVE. Measure the resistance between drain valve terminals. Terminals No. 1 - No. 2Is the resistance 10 - 100 ohms?Repair the poor contact of drain valve connector.Replace the drain valve. Ref. to DRAIN VALVE .
NOTE
In this case, temporary open or short circuit of harness or temporary poor contact of connector may be the cause.
NOTE
In this case, repair the following item: Open circuit of harness between ECM and drain valve connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Turn the ignition switch to ON. Read the data of fuel tank pressure sensor signal using the Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value less than -7.41 kPa (-55.6 mmHg,-2.19 inHg)?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK FUEL TANK PRESSURE SENSOR POWER SUPPLY. Turn the ignition switch to OFF. Disconnect the connector from the fuel tank pressure sensor. Turn the ignition switch to ON. Measure the voltage between the fuel tank pressure sensor connector and chassis ground. Connector & terminal (R47) No. 3 (+) - Chassis ground (-)Is the voltage 4.5 V or more?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and fuel tank pressure sensor connector Poor contact of ECM connector Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND FUEL TANK PRESSURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance of harness between the ECM and fuel tank pressure sensor connector. Connector & terminal (B136) No. 21 - (R47) No. 2Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and fuel tank pressure sensor connector Poor contact of coupling connector
4 CHECK HARNESS BETWEEN ECM AND FUEL TANK PRESSURE SENSOR CONNECTOR. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 21 - Chassis groundIs the resistance 1 Mohms or more?Go to step 5 .Repair the ground short circuit of harness between ECM and fuel tank pressure sensor connector.
5 CHECK FOR POOR CONTACT. Check for poor contact between the ECM and fuel tank pressure sensor connector.Is there poor contact of the ECM or fuel tank pressure sensor connector?Repair the poor contact of the ECM or fuel tank pressure sensor connector.Replace the fuel tank pressure sensor. Ref. to FUEL TANK PRESSURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, repair the following item: Open circuit of harness between ECM and fuel tank pressure sensor connector Poor contact of ECM connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and fuel tank pressure sensor connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Turn the ignition switch to ON. Read the data of fuel tank pressure sensor signal using the Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value 7.95 kPa (59.6 mmHg, 2.35 inHg) or more?Go to step 2 .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK HARNESS BETWEEN ECM AND FUEL TANK PRESSURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from the fuel tank pressure sensor. Turn the ignition switch to ON. Read the data of fuel tank pressure sensor signal using the Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value 7.95 kPa (59.6 mmHg, 2.35 inHg) or more?Repair the short circuit to power in the harness between ECM and fuel tank pressure sensor connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND FUEL TANK PRESSURE SENSOR CONNECTOR. Turn the ignition switch to OFF. Measure the resistance of harness between fuel tank pressure sensor connector and engine ground. Connector & terminal (R47) No. 1 - Engine groundIs the resistance less than 5 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and fuel tank pressure sensor connector Poor contact of ECM connector Poor contact of coupling connector Poor contact of joint connector
4 CHECK FOR POOR CONTACT. Check for poor contact of the fuel tank pressure sensor connector.Is there poor contact of fuel tank pressure sensor connector?Repair the poor contact of fuel tank pressure sensor connector.Replace the fuel tank pressure sensor. Ref. to FUEL TANK PRESSURE SENSOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit of harness between ECM and fuel tank pressure sensor connector Poor contact of ECM connector Poor contact of coupling connector Poor contact of joint connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FUEL FILLER CAP. Turn the ignition switch to OFF. Check the fuel filler cap. NOTE: The DTC is stored in memory if fuel filler cap is or was loose or if the cap chain has caught while tightening.Is the fuel filler cap tightened securely?Go to step 2 .Tighten fuel filler cap securely.
2 CHECK FUEL FILLER CAP.Is the fuel filler cap genuine?Go to step 3 .Replace with a genuine fuel filler cap.
3 CHECK FUEL FILLER PIPE GASKET.Is there any damage to the seal between fuel filler cap and fuel filler pipe?Repair or replace the fuel filler cap and fuel filler pipe. Ref. to FUEL FILLER PIPE .Go to step 4 .
4 CHECK DRAIN VALVE. Install the delivery (test) mode fuse. Turn the ignition switch to ON. Operate the drain valve using the Subaru Select Monitor. NOTE: Drain valve can be operated using the Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .Does the drain valve operate?Go to step 5 .Replace the drain valve. Ref. to DRAIN VALVE .
5 CHECK PURGE CONTROL SOLENOID VALVE. Operate the purge control solenoid valve using the Subaru Select Monitor. NOTE: Purge control solenoid valve operation can be executed using Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .Does the purge control solenoid valve operate?Go to step 6 .Replace the purge control solenoid valve. Ref. to PURGE CONTROL SOLENOID VALVE .
6 CHECK EVAPORATIVE EMISSION CONTROL SYSTEM LINE. Turn the ignition switch to OFF. Check the delivery (test) mode fuse is removed.Is there any hole of more than 0.5 mm (0.020 in) dia. on evaporation line?Repair or replace the evaporation line. Ref. to FUEL DELIVERY AND EVAPORATION LINES .Go to step 7 .
7 CHECK CANISTER.Is the canister damaged or is there a hole of more than 0.5 mm (0.020 in) dia. in it?Repair or replace the canister. Ref. to CANISTER .Go to step 8 .
8 CHECK FUEL TANK. Remove the fuel tank. Ref. to FUEL TANK .Is the fuel tank damaged or is there any hole of more than 0.5 mm (0.020 in) dia. in it?Repair or replace the fuel tank. Ref. to FUEL TANK .Go to step 9 .
9 CHECK ANY OTHER MECHANICAL TROUBLE IN EVAPORATIVE EMISSION CONTROL SYSTEM.Is there any hole of more than 0.5 mm (0.020 in) dia, crack, clogging, or disconnections, bend, misconnection of hoses or pipes in evaporative emission control system?Repair or replace the hoses or pipes.Repair the poor contact of ECM connector.
NOTE
The DTC is stored in memory if fuel filler cap is or was loose or if the cap chain has caught while tightening.
NOTE
Drain valve can be operated using the Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .
NOTE
Purge control solenoid valve operation can be executed using Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FUEL FILLER CAP. Turn the ignition switch to OFF. Check the fuel filler cap. NOTE: The DTC is stored in memory if fuel filler cap is or was loose or if the cap chain has caught while tightening.Is the fuel filler cap tightened securely?Go to step 2 .Tighten fuel filler cap securely.
2 CHECK FUEL FILLER CAP.Is the fuel filler cap genuine?Go to step 3 .Replace with a genuine fuel filler cap.
3 CHECK FUEL FILLER PIPE GASKET.Is there any damage to the seal between fuel filler cap and fuel filler pipe?Repair or replace the fuel filler cap and fuel filler pipe. Ref. to FUEL FILLER PIPE .Go to step 4 .
4 CHECK DRAIN VALVE. Install the delivery (test) mode fuse. Turn the ignition switch to ON. Operate the drain valve using the Subaru Select Monitor. NOTE: Drain valve can be operated using the Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .Does the drain valve operate?Go to step 5 .Replace the drain valve. Ref. to DRAIN VALVE .
5 CHECK PURGE CONTROL SOLENOID VALVE. Operate the purge control solenoid valve using the Subaru Select Monitor. NOTE: Purge control solenoid valve operation can be executed using Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .Does the purge control solenoid valve operate?Go to step 6 .Replace the purge control solenoid valve. Ref. to PURGE CONTROL SOLENOID VALVE .
6 CHECK EVAPORATIVE EMISSION CONTROL SYSTEM LINE. Turn the ignition switch to OFF. Check the delivery (test) mode fuse is removed.Is there any disconnection, damage or clogging on the evaporation line?Repair or replace the evaporation line. Ref. to FUEL DELIVERY AND EVAPORATION LINES .Go to step 7 .
7 CHECK CANISTER.Is the canister damaged?Repair or replace the canister. Ref. to CANISTER .Go to step 8 .
8 CHECK FUEL TANK. Remove the fuel tank. Ref. to FUEL TANK .Is the fuel tank damaged?Repair or replace the fuel tank. Ref. to FUEL TANK .Go to step 9 .
9 CHECK ANY OTHER MECHANICAL TROUBLE IN EVAPORATIVE EMISSION CONTROL SYSTEM.Are there holes, cracks, clogging, or disconnections, mis-connection of hoses or pipes in evaporative emission control system?Repair or replace the hoses or pipes.Repair the poor contact of ECM connector.
NOTE
The DTC is stored in memory if fuel filler cap is or was loose or if the cap chain has caught while tightening.
NOTE
Drain valve can be operated using the Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .
NOTE
Purge control solenoid valve operation can be executed using Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK OUTPUT SIGNAL OF ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B137) No. 6 (+) - Chassis ground (-)Is the voltage 10 V or more?Go to step 2 .Go to step 3 .
2 CHECK FOR POOR CONTACT. Check for poor contact of ECM connector.Is there poor contact of ECM connector?Repair the poor contact of ECM connector.Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary open or short circuit of harness or temporary poor contact of connector may be the cause.
3 CHECK POWER SUPPLY TO PURGE CONTROL SOLENOID VALVE. Measure the voltage between purge control solenoid valve and engine ground. Connector & terminal (E4) No. 1 (+) - Engine ground (-)Is the voltage 10 V or more?Go to step 4 .Repair the power supply circuit.
4 CHECK HARNESS BETWEEN ECM AND PURGE CONTROL SOLENOID VALVE CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and purge control solenoid valve. Measure the resistance between the purge control solenoid valve connector and engine ground. Connector & terminal (E4) No. 2 - Engine groundIs the resistance 1 Mohms or more?Go to step 5 .Repair the ground short circuit of harness between ECM and purge control solenoid valve connector.
5 CHECK HARNESS BETWEEN ECM AND PURGE CONTROL SOLENOID VALVE CONNECTOR. Measure the resistance of harness between ECM and purge control solenoid valve. Connector & terminal (B137) No. 6 - (E4) No. 2Is the resistance less than 1 ohms?Go to step 6 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and purge control solenoid valve connector Poor contact of coupling connector
6 CHECK PURGE CONTROL SOLENOID VALVE. Remove the purge control solenoid valve. Measure the resistance between purge control solenoid valve terminals. Terminals No. 1 - No. 2Is the resistance 10 - 100 ohms?Repair the poor contact of purge control solenoid valve connector.Replace the purge control solenoid valve. Ref. to PURGE CONTROL SOLENOID VALVE .
NOTE
In this case, temporary open or short circuit of harness or temporary poor contact of connector may be the cause.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and purge control solenoid valve connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND PURGE CONTROL SOLENOID VALVE CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and purge control solenoid valve. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B137) No. 6 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the short circuit of harness to power supply between ECM and purge control solenoid valve connector.Go to step 2 .
2 CHECK PURGE CONTROL SOLENOID VALVE. Turn the ignition switch to OFF. Measure the resistance between purge control solenoid valve terminals. Terminals No. 1 - No. 2Is the resistance less than 1 ohms?Replace the purge control solenoid valve. Ref. to PURGE CONTROL SOLENOID VALVE .Repair the poor contact of ECM connector.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FOR ANY OTHER DTC ON DISPLAY.Is any other DTC displayed?Check the appropriate DTC using the "List of Diagnostic Trouble Code (DTC)". Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .Go to step 2 .
2 CHECK AIR CLEANER ELEMENT. Turn the ignition switch to OFF. Check the air cleaner element.Is there excessive clogging on air cleaner element?Replace the air cleaner element. Ref. to AIR CLEANER ELEMENT .Go to step 3 .
3 CHECK ELECTRONIC THROTTLE CONTROL. Remove the electronic throttle control. Ref. to REMOVAL , Throttle Body. Check the electronic throttle control.Are foreign matter found inside electronic throttle control?Remove foreign matter from electronic throttle control.Perform the diagnosis of DTC P2101. Ref. to DTC P2101 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT RANGE/PERFORMANCE , Diagnostic Procedure with Diagnostic Trouble Code (DTC).

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FOR ANY OTHER DTC ON DISPLAY.Is any other DTC displayed?Check the appropriate DTC using the "List of Diagnostic Trouble Code (DTC)". Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .Go to step 2 .
2 CHECK AIR INTAKE SYSTEM. Start and idle the engine. Check the following items. Loose installation of intake manifold and throttle body Cracks of intake manifold gasket and throttle body gasket Disconnection of vacuum hosesIs there any fault in air intake system?Repair air suction and leaks.Go to step 3 .
3 CHECK ELECTRONIC THROTTLE CONTROL. Turn the ignition switch to OFF. Remove the electronic throttle control. Ref. to REMOVAL , Throttle Body. Check the electronic throttle control.Are foreign matter found inside electronic throttle control?Remove foreign matter from electronic throttle control.Perform the diagnosis of DTC P2101. Ref. to DTC P2101 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT RANGE/PERFORMANCE , Diagnostic Procedure with Diagnostic Trouble Code (DTC).

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FOR ANY OTHER DTC ON DISPLAY.Is any other DTC displayed?Check the appropriate DTC using the "List of Diagnostic Trouble Code (DTC)". Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .Go to step 2 .
2 CHECK HARNESS BETWEEN ECM AND STARTER RELAY CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 16 (+) - Chassis ground (-): NOTE: For CVT model, place the select lever in "P" range or "N" range.Is the voltage 10 V or more?Repair the short circuit to power supply in harness between ECM and starter relay connector.Repair the poor contact of ECM connector.
NOTE
For CVT model, place the select lever in "P" range or "N" range.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FOR ANY OTHER DTC ON DISPLAY.Is any other DTC displayed?Check the appropriate DTC using the "List of Diagnostic Trouble Code (DTC)". Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
NOTE
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK INPUT SIGNAL OF ECM. Turn the ignition switch to ON. Place the shift lever in a position other than neutral. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 35 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the poor contact of ECM connector.Go to step 2 .
2 CHECK HARNESS BETWEEN ECM AND NEUTRAL POSITION SWITCH CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and neutral position switch. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 35 - Chassis groundIs the resistance 1 Mohms. or more?Replace the neutral position switch. Ref. to SWITCHES AND HARNESS .Repair the short circuit to ground harness between ECM and neutral position switch connector.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK SELECT CABLE.Is there any fault in select cable?Repair or adjust the select cable. Ref. to SELECT CABLE .Go to step 2 .
2 CHECK INPUT SIGNAL OF ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground with select lever at "P" range and "N" range. Connector & terminal (B136) No. 35 (+) - Chassis ground (-)Is the voltage less than 1 V?Repair the poor contact of ECM connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND INHIBITOR SWITCH CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and inhibitor switch. Measure the resistance of harness between ECM and inhibitor switch connector. Connector & terminal (B136) No. 35 - (T7) No. 6Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and inhibitor switch connector Poor contact of coupling connector
4 CHECK INHIBITOR SWITCH GROUND LINE. Measure the resistance of harness between inhibitor switch connector and engine ground. Connector & terminal (T7) No. 9 - Engine groundIs the resistance less than 5 ohms?Replace the inhibitor switch. Ref. to INHIBITOR SWITCH .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between inhibitor switch connector and starter motor ground line Poor contact of coupling connector Poor contact of starter motor connector Poor contact of starter motor ground Starter motor
NOTE
In this case, repair the following item: Open circuit in harness between ECM and inhibitor switch connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between inhibitor switch connector and starter motor ground line Poor contact of coupling connector Poor contact of starter motor connector Poor contact of starter motor ground Starter motor

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK INPUT SIGNAL OF ECM. Turn the ignition switch to ON. Place the shift lever in neutral. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 35 (+) - Chassis ground (-)Is the voltage less than 1 V?Repair the poor contact of ECM connector.Go to step 2 .
2 CHECK HARNESS BETWEEN ECM AND NEUTRAL POSITION SWITCH CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and neutral position switch. Measure the resistance of harness between ECM and neutral position switch connector. Connector & terminal (B136) No. 35 - (B25) No. 2: (B136) No. 4 - (B25) No. 1Is the resistance less than 1 ohms?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and neutral position switch connector Poor contact of joint connector
3 CHECK NEUTRAL POSITION SWITCH. Place the shift lever in neutral. Measure the resistance between neutral position switch terminals. Terminals No. 1 - No. 2Is the resistance less than 1 ohms?Repair the poor contact of neutral position switch connector.Replace the neutral position switch. Ref. to SWITCHES AND HARNESS .
NOTE
In this case, repair the following item: Open circuit in harness between ECM and neutral position switch connector Poor contact of joint connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
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. Turn the ignition switch to OFF. Disconnect the connectors from ECM and front oxygen (A/F) sensor. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector. Connector & terminal (B136) No. 18 - (E24) No. 2: (B136) No. 19 - (E24) No. 1Is the resistance less than 1 ohms?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 FOR POOR CONTACT. Check for poor contact of the front oxygen (A/F) sensor connector.Is there poor contact of front oxygen (A/F) sensor connector?Repair the poor contact of front oxygen (A/F) sensor connector.Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .
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

DIAGNOSTIC PROCEDURE

StepCheckYesNo
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. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 18 - Chassis ground: (B136) No. 19 - Chassis groundIs the resistance 1 Mohms or more?Go to step 3 .Repair the ground short circuit of harness between ECM and front oxygen (A/F) sensor connector.
3 CHECK OUTPUT SIGNAL FOR ECM. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 19 (+) - Chassis ground (-)Is the voltage 4.5 V or more?Go to step 5 .Go to step 4 .
4 CHECK OUTPUT SIGNAL FOR ECM. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 18 (+) - Chassis ground (-)Is the voltage 4.95 V or more?Go to step 5 .Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .
5 CHECK OUTPUT SIGNAL FOR ECM. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 18 (+) - Chassis ground (-): (B136) No. 19 (+) - Chassis ground (-)Is the voltage 8 V or more?Repair the short circuit of harness to power supply between ECM and front oxygen (A/F) sensor connector. After repair, replace the ECM. Ref. to ENGINE CONTROL MODULE (ECM) .Repair the poor contact of ECM connector.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FOR ANY OTHER DTC ON DISPLAY.Is any other DTC displayed?Check the appropriate DTC using the "List of Diagnostic Trouble Code (DTC)". Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .Go to step 2 .
2 CHECK DRAIN HOSE. Check the drain hose for clogging.Is there clogging in the drain hose?Replace the drain hose.Go to step 3 .
3 CHECK DRAIN VALVE OPERATION. Turn the ignition switch to OFF. Install the delivery (test) mode fuse. Turn the ignition switch to ON. Operate the drain valve. NOTE: Drain valve can be operated using the Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .Does the drain valve operate?Repair the poor contact of ECM connector.Replace the drain valve. Ref. to DRAIN VALVE .
NOTE
Drain valve can be operated using the Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK POWER SUPPLY TO EGR VALVE. Turn the ignition switch to OFF. Disconnect the connector from EGR valve. Turn the ignition switch to ON. Measure the voltage between EGR valve connector and engine ground. Connector & terminal (E18) No. 2 (+) - Engine ground (-): (E18) No. 5 (+) - Engine ground (-)Is the voltage 10 V or more?Go to step 2 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between EGR valve and main relay connector Poor contact of coupling connector
2 CHECK HARNESS BETWEEN ECM AND EGR VALVE CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM and EGR valve connector. Connector & terminal DTC P1492; (B134) No. 8 - (E18) No. 3: DTC P1494; (B134) No. 9 - (E18) No. 1: DTC P1496; (B134) No. 20 - (E18) No. 4: DTC P1498; (B134) No. 30 - (E18) No. 6Is the resistance less than 1 ohms?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and EGR valve connector Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND EGR VALVE CONNECTOR. Disconnect the connector from ECM. Measure the resistance between ECM and chassis ground. Connector & terminal DTC P1492; (B134) No. 8 - Chassis ground: DTC P1494; (B134) No. 9 - Chassis ground: DTC P1496; (B134) No. 20 - Chassis ground: DTC P1498; (B134) No. 30 - Chassis groundIs the resistance 1 Mohms or more?Go to step 4 .Repair the ground short in harness between ECM and EGR valve connector.
4 CHECK FOR POOR CONTACT. Check for poor contact of ECM and EGR valve connector.Is there poor contact of ECM or EGR valve connector?Repair the poor contact of ECM or EGR valve connector.Replace the EGR valve. Ref. to EGR VALVE .
NOTE
In this case, repair the following item: Open circuit in harness between EGR valve and main relay connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit in harness between ECM and EGR valve connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND EGR VALVE CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and EGR valve. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal DTC P1493; (B134) No. 8 (+) - Chassis ground (-): DTC P1495; (B134) No. 9 (+) - Chassis ground (-): DTC P1497; (B134) No. 20 (+) - Chassis ground (-): DTC P1499; (B134) No. 30 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the short circuit to power in the harness between the ECM and EGR valve connectors.Go to step 2 .
2 CHECK EGR VALVE. Measure the resistance between EGR valve terminals. Terminals DTC P1493; No. 2 - No. 3: DTC P1493; No. 5 - No. 3: DTC P1495; No. 2 - No. 1: DTC P1495; No. 5 - No. 1: DTC P1497; No. 2 - No. 4: DTC P1497; No. 5 - No. 4: DTC P1499; No. 2 - No. 6: DTC P1499; No. 5 - No. 6Is the resistance 20 ohms or more?Repair the poor contact of ECM connector.Replace the EGR valve. Ref. to EGR VALVE .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK INPUT SIGNAL OF ECM. Turn the ignition switch to OFF. Measure the voltage between ECM and chassis ground. Connector & terminal (B136) No. 2 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the poor contact of ECM connector.Go to step 2 .
2 CHECK HARNESS BETWEEN ECM AND MAIN FUSE BOX CONNECTOR. Disconnect the connector from ECM. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 2 - Chassis groundIs the resistance 1 Mohms or more?Go to step 3 .Repair the ground short circuit of harness between ECM and battery terminal.
3 CHECK M/B FUSE NO. 12 (MAIN FUSE BOX).Is the fuse blown out?Replace the fuse.Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and battery Poor contact of ECM connector Poor contact of battery terminal
NOTE
In this case, repair the following item: Open circuit in harness between ECM and battery Poor contact of ECM connector Poor contact of battery terminal

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FOR ANY OTHER DTC ON DISPLAY.Is any other DTC displayed?Check the appropriate DTC using the "List of Diagnostic Trouble Code (DTC)". Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .Go to step 2 .
2 CHECK ENGINE OIL.Is there a proper amount of engine oil?Go to step 3 .Replace engine oil. Ref. to REPLACEMENT , Engine Oil.
3 CHECK EXHAUST SYSTEM.Are there holes or loose bolts on exhaust system?Repair the exhaust system.Go to step 4 .
4 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 5 .
5 CHECK FUEL PRESSURE. WARNING: Place "NO OPEN FLAMES" signs near the working area. CAUTION: Be careful not to spill fuel. Measure the fuel pressure. Ref. to INSPECTION , Fuel Pressure. CAUTION: Release fuel pressure before removing the fuel pressure gauge.Is the measured value 339.5 - 360.5 kPa (3.5 - 3.7 kg/cm 2 , 49 - 52 psi)?Go to step 6 .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
6 CHECK ENGINE COOLANT TEMPERATURE SENSOR. Start the engine and warm up completely. Read the data of engine coolant temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the temperature 75°C (167°F) or more?Go to step 7 .Replace the engine coolant temperature sensor. Ref. to ENGINE COOLANT TEMPERATURE SENSOR .
7 CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F). For CVT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position. Turn the A/C switch to OFF. Turn all the accessory switches to OFF. Read the data of mass airflow and intake air temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value 2.0 - 5.0 g/s (0.26 - 0.66 lb/m)?Go to step 8 .Replace the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
8 CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F). For CVT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position. Turn the A/C switch to OFF. Turn all the accessory switches to OFF. Open the front hood. Measure the ambient temperature. Read the data of mass air flow and intake air temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. 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 temperature. Is the obtained value -10 - 50°C (-18 -90°F)?Go to step 9 .Check the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
9 CHECK OUTPUT SIGNAL OF ECM. Turn the ignition switch to ON. 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 14 .Go to step 10 .
10 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from fuel injector on faulty cylinders. 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 groundIs the resistance 1 Mohms or more?Go to step 11 .Repair the ground short circuit of harness between ECM and fuel injector connector.
11 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. Measure the resistance of harness between ECM and fuel injector 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. 1Is the resistance less than 1 ohms?Go to step 12 .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
12 CHECK FUEL INJECTOR. Measure the resistance between fuel injector terminals on faulty cylinder. Terminals No. 1 - No. 2Is the resistance 5 - 20 ohms?Go to step 13 .Replace the faulty fuel injector. Ref. to FUEL INJECTOR .
13 CHECK POWER SUPPLY LINE. Turn the ignition switch to ON. Measure the voltage between fuel injector and engine ground on faulty cylinders. 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 connector and fuel injector connector on faulty cylinders Poor contact of coupling connector Poor contact of main relay connector
14 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from fuel injector on faulty cylinders. Turn the ignition switch to ON. 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 the harness between the ECM and fuel injector.Go to step 15 .
15 CHECK FUEL INJECTOR. Turn the ignition switch to OFF. Measure the resistance between fuel injector terminals on faulty cylinder. Terminals No. 1 - No. 2Is the resistance less than 1 ohms?Replace the faulty fuel injector. Ref. to FUEL INJECTOR .Go to step 16 .
16 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. Ref. to CAMSHAFT POSITION SENSOR . Ref. to CRANKSHAFT POSITION SENSOR .Go to step 17 .
17 CHECK CRANK SPROCKET. Remove the timing belt cover. Ref. to REMOVAL , Timing Belt Cover.Is the crank sprocket rusted or does it have broken teeth?Replace the crank sprocket. Ref. to CRANK SPROCKET .Go to step 18 .
18 CHECK INSTALLATION CONDITION OF TIMING BELT.Turn the crankshaft using ST, and align the alignment mark on crank sprocket with alignment mark on cylinder block. ST 499987500 CRANKSHAFT SOCKETIs the timing belt dislocated from its proper position? Repair the installation condition of timing belt. Ref. to TIMING BELT .Go to step 19 .
19 CHECK ELECTRONIC THROTTLE CONTROL RELAY. Turn the ignition switch to OFF. Remove the electronic throttle control relay. Connect the battery to terminals No. 13 and No. 14 of electronic throttle control relay. Measure the resistance between electronic throttle control relay terminals. Terminals No. 15 - No. 16Is the resistance less than 1 ohms?Go to step 20 .Replace the electronic throttle control relay. Ref. to ELECTRONIC THROTTLE CONTROL RELAY .
20 CHECK POWER SUPPLY OF ELECTRONIC THROTTLE CONTROL RELAY. Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 16 (+) - Chassis ground (-)Is the voltage 10 V or more?Go to step 21 .Repair the open or ground short circuit of power supply circuit.
21 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Disconnect the connector from ECM. Turn the ignition switch to ON. Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 14 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the short circuit to power in the harness between ECM and electronic throttle control relay connector.Go to step 22 .
22 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Turn the ignition switch to OFF. Measure the resistance between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 14 - Chassis ground: (B220) No. 15 - Chassis groundIs the resistance 1 Mohms or more?Go to step 23 .Repair the short circuit in harness to ground between ECM and electronic throttle control relay connector.
23 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Measure the resistance between ECM and electronic throttle control relay connector. Connector & terminal (B135) No. 17 - (B220) No. 14: (B135) No. 7 - (B220) No. 15Is the resistance less than 1 ohms?Go to step 24 .Repair the open circuit in harness between ECM and electronic throttle control relay connector.
24 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and electronic throttle control. Measure the resistance between ECM and chassis ground. Connector & terminal (B134) No. 19 - Chassis ground: (B134) No. 18 - Chassis ground: (B134) No. 18 - (B136) No. 4: (B134) No. 28 - Chassis groundIs the resistance 1 Mohms or more?Go to step 25 .Repair the ground short circuit of harness between ECM and electronic throttle control connector.
25 CHECK SHORT CIRCUIT INSIDE THE ECM. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 6 - Engine ground: (E57) No. 4 - Engine groundIs the resistance 1 MD or more?Go to step 26 .Repair the ground short circuit of harness between ECM and electronic throttle control connector. Replace the ECM if defective. Ref. to ENGINE CONTROL MODULE (ECM) .
26 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Disconnect the connector from ECM. Measure the resistance of harness between ECM and electronic throttle control connector. Connector & terminal (B134) No. 18 - (E57) No. 6: (B134) No. 28 - (E57) No. 4: (B134) No. 29 - (E57) No. 3Is the resistance less than 1 ohms?Go to step 27 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
27 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 3 - Engine groundIs the resistance less than 5 ohms?Go to step 28 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
28 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to ON. Measure the voltage between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 6 (+) - Engine ground (-): (E57) No. 4 (+) - Engine ground (-)Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.Go to step 29 .
29 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B134) No. 19 - (B134) No. 18: (B134) No. 19 - (B134) No. 28Is the resistance 1 Mohms or more?Go to step 30 .Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.
30 CHECK SENSOR OUTPUT. Connect all connectors. Turn the ignition switch to ON. Read the data of main throttle sensor signal using Subaru Select Monitor. NOTE: For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .Is the voltage 0.81 - 0.87 V?Go to step 31 .Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to THROTTLE BODY .
31 CHECK SENSOR OUTPUT. Read the data of sub throttle sensor signal using Subaru Select Monitor. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .Is the voltage 1.64 - 1.70 V?Go to step 32 .Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to THROTTLE BODY .
32 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and electronic throttle control. Measure the resistance between ECM and electronic throttle control connector. Connector & terminal (B134) No. 2 - (E57) No. 2: (B134) No. 1 - (E57) No. 1Is the resistance less than 1 ohms?Go to step 33 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
33 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 2 (+) - Engine ground (-): (E57) No. 1 (+) - Engine ground (-)Is the voltage 5 V or more?Repair the short circuit to power in the harness between ECM and electronic throttle control.Go to step 34 .
34 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 2 - Engine ground: (E57) No. 1 - Engine groundIs the resistance 1 Mohms or more?Go to step 35 .Repair the ground short circuit of harness between ECM and electronic throttle control connector.
35 CHECK HARNESS BETWEEN ELECTRONIC THROTTLE CONTROL CONNECTOR. Measure the resistance between electronic throttle control connectors. Connector & terminal (E57) No. 2 - (E57) No. 1Is the resistance 1 Mohms or more?Go to step 36 .Repair the short circuit of harness between ECM and electronic throttle control connector.
36 CHECK ELECTRONIC THROTTLE CONTROL GROUND CIRCUIT. Measure the resistance between ECM and chassis ground. Connector & terminal (B134) No. 3 - Chassis ground: (B134) No. 4 - Chassis ground: (B134) No. 6 - Chassis ground: (B137) No. 1 - Chassis ground: (B137) No. 3 - Chassis groundIs the resistance less than 5 ohms?Go to step 37 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of coupling connector
37 CHECK ELECTRONIC THROTTLE CONTROL. Measure the resistance between electronic throttle control terminals. Terminals No. 2 - No. 1Is the resistance 50 ohms or less?Go to step 38 .Replace the electronic throttle control. Ref. to THROTTLE BODY .
38 CHECK ELECTRONIC THROTTLE CONTROL. Move the throttle valve to the fully open and fully closed positions with fingers. Check that the valve returns to the specified position when releasing fingers.Does the valve return to the specified position? Standard value: 3 mm (0.12 in) from fully closed positionRepair the poor contact of ECM connector.Replace the electronic throttle control. Ref. to THROTTLE BODY .
WARNING
Place "NO OPEN FLAMES" signs near the working area.
CAUTION
Be careful not to spill fuel.
CAUTION
Release fuel pressure before removing the fuel pressure gauge.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and fuel injector connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit in harness between the main relay connector and fuel injector connector on faulty cylinders Poor contact of coupling connector Poor contact of main relay connector
NOTE
In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
NOTE
For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .
NOTE
In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FOR ANY OTHER DTC ON DISPLAY.Is any other DTC displayed?Check DTC using "List of Diagnostic Trouble Code (DTC)". Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .Go to step 2 .
2 CHECK FRONT OXYGEN (A/F) SENSOR CONNECTOR AND COUPLING CONNECTOR.Has water entered the connector?Completely remove any water inside.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and front oxygen (A/F) sensor. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector. Connector & terminal (B136) No. 19 - (E24) No. 1: (B136) No. 18 - (E24) No. 2Is the resistance less than 1 ohms?Go to step 4 .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
4 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 groundIs the resistance 1 Mohms or more?Go to step 5 .Repair the ground short circuit of harness between ECM and front oxygen (A/F) sensor connector.
5 CHECK OUTPUT SIGNAL FOR ECM. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between front oxygen (A/F) sensor connector and chassis ground. Connector & terminal (E24) No. 1 (+) - Chassis ground (-)Is the voltage 4.5 V or more?Go to step 7 .Go to step 6 .
6 CHECK OUTPUT SIGNAL FOR ECM. Measure the voltage between front oxygen (A/F) sensor connector and chassis ground. Connector & terminal (E24) No. 2 (+) - Chassis ground (-)Is the voltage 4.95 V or more?Go to step 7 .Go to step 8 .
7 CHECK OUTPUT SIGNAL FOR ECM. Measure the voltage between front oxygen (A/F) sensor connector and chassis ground. Connector & terminal (E24) No. 1 (+) - Chassis ground (-): (E24) No. 2 (+) - Chassis ground (-)Is the voltage 8 V or more?Repair the short circuit of harness to power supply between ECM and front oxygen (A/F) sensor connector. After repair, replace the ECM. Ref. to ENGINE CONTROL MODULE (ECM) .Repair the poor contact of ECM connector.
8 CHECK EXHAUST SYSTEM.Are there holes or loose bolts on exhaust system?Repair the exhaust system.Go to step 9 .
9 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 10 .
10 CHECK FUEL PRESSURE. WARNING: Place "NO OPEN FLAMES" signs near the working area. CAUTION: Be careful not to spill fuel. Connect the front oxygen (A/F) sensor connector. Measure the fuel pressure. Ref. to INSPECTION , Fuel Pressure. CAUTION: Release fuel pressure before removing the fuel pressure gauge.Is the measured value 339.5 - 360.5 kPa (3.5 - 3.7 kg/cm 2 , 49 - 52 psi)?Go to step 11 .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
11 CHECK ENGINE COOLANT TEMPERATURE SENSOR. Start the engine and warm up completely. Read the data of engine coolant temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the temperature 75°C (167°F) or more?Go to step 12 .Replace the engine coolant temperature sensor. Ref. to ENGINE COOLANT TEMPERATURE SENSOR .
12 CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F). For CVT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position. Turn the A/C switch to OFF. Turn all the accessory switches to OFF. Read the data of mass air flow and intake air temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value 2.0 - 5.0 g/s (0.26 - 0.66 lb/m)?Go to step 13 .Replace the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
13 CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F). For CVT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position. Turn the A/C switch to OFF. Turn all the accessory switches to OFF. Open the front hood. Measure the ambient temperature. Read the data of mass air flow and intake air temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. 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 temperature. Is the obtained value -10 - 50°C (-18 - 90°F)?Go to step 14 .Check the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
14 CHECK REAR OXYGEN SENSOR DATA. Warm up the engine until engine coolant temperature is above 75°C (167°F), and keep the engine speed at 3,000 RPM. (2 minutes maximum) Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Depress the clutch pedal. (MT model) Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 490 mV or more?Go to step 15 .Go to step 16 .
15 CHECK REAR OXYGEN SENSOR DATA. Warm up the engine until engine coolant temperature is above 75°C (167°F), and rapidly reduce the engine speed from 3,000 RPM. Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Depress the clutch pedal. (MT model) Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 250 mV or less?Go to step 17 .Go to step 16 .
16 CHECK REAR OXYGEN SENSOR CONNECTOR AND COUPLING CONNECTOR.Has water entered the connector?Completely remove any water inside.Go to step 18 .
17 CHECK FRONT OXYGEN (A/F) SENSOR USING REAR OXYGEN SENSOR SIGNAL 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. Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is a voltage of 250 mV or less maintained for 5 minutes or more?Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .Go to step 18 .
18 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and rear oxygen sensor. Measure the resistance of harness between ECM and rear oxygen sensor connector. Connector & terminal (B136) No. 20 - E250 No. 3: (B134) No. 29 - E250 No. 4Is the resistance less than 1 ohms?Go to step 19 .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
19 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between rear oxygen sensor connector and chassis ground. Connector & terminal E250 No. 3 (+) - Chassis ground (-)Is the voltage 0.2 - 0.5 V?Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .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 ECM connector Poor contact of coupling 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
WARNING
Place "NO OPEN FLAMES" signs near the working area.
CAUTION
Be careful not to spill fuel.
CAUTION
Release fuel pressure before removing the fuel pressure gauge.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Depress the clutch pedal. (MT model) Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Depress the clutch pedal. (MT model) Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of ECM connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK FOR ANY OTHER DTC ON DISPLAY.Is any other DTC displayed?Check DTC using "List of Diagnostic Trouble Code (DTC)". Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .Go to step 2 .
2 CHECK FRONT OXYGEN (A/F) SENSOR CONNECTOR AND COUPLING CONNECTOR.Has water entered the connector?Completely remove any water inside.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and front oxygen (A/F) sensor. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector. Connector & terminal (B136) No. 19 - (E24) No. 1: (B136) No. 18 - (E24) No. 2Is the resistance less than 1 ohms?Go to step 4 .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
4 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 groundIs the resistance 1 Mohms or more?Go to step 5 .Repair the ground short circuit of harness between ECM and front oxygen (A/F) sensor connector.
5 CHECK OUTPUT SIGNAL FOR ECM. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between front oxygen (A/F) sensor connector and chassis ground. Connector & terminal (E24) No. 1 (+) - Chassis ground (-)Is the voltage 4.5 V or more?Go to step 7 .Go to step 6 .
6 CHECK OUTPUT SIGNAL FOR ECM. Measure the voltage between front oxygen (A/F) sensor connector and chassis ground. Connector & terminal (E24) No. 2 (+) - Chassis ground (-)Is the voltage 4.95 V or more?Go to step 7 .Go to step 8 .
7 CHECK OUTPUT SIGNAL FOR ECM. Measure the voltage between front oxygen (A/F) sensor connector and chassis ground. Connector & terminal (E24) No. 1 (+) - Chassis ground (-): (E24) No. 2 (+) - Chassis ground (-)Is the voltage 8 V or more?Repair the short circuit of harness to power supply between ECM and front oxygen (A/F) sensor connector. After repair, replace the ECM. Ref. to ENGINE CONTROL MODULE (ECM) .Repair the poor contact of ECM connector.
8 CHECK EXHAUST SYSTEM.Are there holes or loose bolts on exhaust system?Repair the exhaust system.Go to step 9 .
9 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 10 .
10 CHECK FUEL PRESSURE. WARNING: Place "NO OPEN FLAMES" signs near the working area. CAUTION: Be careful not to spill fuel. Connect the front oxygen (A/F) sensor connector. Measure the fuel pressure. Ref. to INSPECTION , Fuel Pressure. CAUTION: Release fuel pressure before removing the fuel pressure gauge.Is the measured value 339.5 - 360.5 kPa (3.5 - 3.7 kg/cm 2 , 49 - 52 psi)?Go to step 11 .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
11 CHECK ENGINE COOLANT TEMPERATURE SENSOR. Start the engine and warm up completely. Read the data of engine coolant temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the temperature 75°C (167°F) or more?Go to step 12 .Replace the engine coolant temperature sensor. Ref. to ENGINE COOLANT TEMPERATURE SENSOR .
12 CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F). For CVT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position. Turn the A/C switch to OFF. Turn all the accessory switches to OFF. Read the data of mass air flow and intake air temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the measured value 2.0 - 5.0 g/s (0.26 - 0.66 lb/m)?Go to step 13 .Replace the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
13 CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F). For CVT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position. Turn the A/C switch to OFF. Turn all the accessory switches to OFF. Open the front hood. Measure the ambient temperature. Read the data of mass air flow and intake air temperature sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. 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 temperature. Is the obtained value -10 - 50°C (-18 -90°F)?Go to step 14 .Check the mass air flow and intake air temperature sensor. Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .
14 CHECK REAR OXYGEN SENSOR DATA. Warm up the engine until engine coolant temperature is above 75°C (167°F), and keep the engine speed at 3,000 RPM. (2 minutes maximum) Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Depress the clutch pedal. (MT model) Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 490 mV or more?Go to step 15 .Go to step 16 .
15 CHECK REAR OXYGEN SENSOR DATA. Warm up the engine until engine coolant temperature is above 75°C (167°F), and rapidly reduce the engine speed from 3,000 RPM. Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Depress the clutch pedal. (MT model) Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is the voltage 250 mV or less?Go to step 17 .Go to step 16 .
16 CHECK REAR OXYGEN SENSOR CONNECTOR AND COUPLING CONNECTOR.Has water entered the connector?Completely remove any water inside.Go to step 18 .
17 CHECK FRONT OXYGEN (A/F) SENSOR USING REAR OXYGEN SENSOR SIGNAL. 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. Read the data of rear oxygen sensor signal using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.Is a voltage of 0.8 V or more maintained for 5 minutes or more?Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR .Go to step 18 .
18 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM and rear oxygen sensor. Measure the resistance of harness between ECM and rear oxygen sensor connector. Connector & terminal (B136) No. 20 - E250 No. 3: (B134) No. 29 - E250 No. 4Is the resistance less than 1 ohms?Go to step 19 .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
19 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between rear oxygen sensor connector and chassis ground. Connector & terminal E250 No. 3 (+) - Chassis ground (-)Is the voltage 0.2 - 0.5 V?Replace the rear oxygen sensor. Ref. to REAR OXYGEN SENSOR .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 ECM connector Poor contact of coupling 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
WARNING
Place "NO OPEN FLAMES" signs near the working area.
CAUTION
Be careful not to spill fuel.
CAUTION
Release fuel pressure before removing the fuel pressure gauge.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Depress the clutch pedal. (MT model) Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Depress the clutch pedal. (MT model) Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR . General scan tool For detailed operation procedures, refer to the general scan tool operation manual.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit in harness between ECM and rear oxygen sensor connector Poor contact of ECM connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK ELECTRONIC THROTTLE CONTROL RELAY. Turn the ignition switch to OFF. Remove the electronic throttle control relay. Connect the battery to terminals No. 13 and No. 14 of electronic throttle control relay. Measure the resistance between electronic throttle control relay terminals. Terminals No. 15 - No. 16Is the resistance less than 1 ohms?Go to step 2 .Replace the electronic throttle control relay. Ref. to ELECTRONIC THROTTLE CONTROL RELAY .
2 CHECK POWER SUPPLY OF ELECTRONIC THROTTLE CONTROL RELAY. Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 16 (+) - Chassis ground (-)Is the voltage 10 V or more?Go to step 3 .Repair the open or ground short circuit of power supply circuit.
3 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Disconnect the connector from ECM. Turn the ignition switch to ON. Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 14 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the short circuit to power in the harness between ECM and electronic throttle control relay connector.Go to step 4 .
4 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Turn the ignition switch to OFF. Measure the resistance between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 14 - Chassis ground: (B220) No. 15 - Chassis groundIs the resistance 1 Mohms or more?Go to step 5 .Repair the short circuit in harness to ground between ECM and electronic throttle control relay connector.
5 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Measure the resistance between ECM and electronic throttle control relay connector. Connector & terminal (B135) No. 17 - (B220) No. 14: (B135) No. 7 - (B220) No. 15Is the resistance less than 1 ohms?Go to step 6 .Repair the open circuit in harness between ECM and electronic throttle control relay connector.
6 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from electronic throttle control. Measure the resistance between ECM and chassis ground. Connector & terminal (B134) No. 19 - Chassis ground: (B134) No. 18 - Chassis ground: (B134) No. 18 - (B136) No. 4: (B134) No. 28 - Chassis groundIs the resistance 1 Mohms or more?Go to step 7 .Repair the ground short circuit of harness between ECM and electronic throttle control connector.
7 CHECK SHORT CIRCUIT INSIDE THE ECM. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 6 - Engine ground: (E57) No. 4 - Engine groundIs the resistance 1 Mohms or more?Go to step 8 .Repair the ground short circuit of harness between ECM and electronic throttle control connector. Replace the ECM if defective. Ref. to ENGINE CONTROL MODULE (ECM) .
8 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Disconnect the connector from ECM. Measure the resistance of harness between ECM and electronic throttle control connector. Connector & terminal (B134) No. 18 - (E57) No. 6: (B134) No. 28 - (E57) No. 4: (B134) No. 29 - (E57) No. 3Is the resistance less than 1 ohms?Go to step 9 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
9 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 3 - Engine groundIs the resistance less than 5 ohms?Go to step 10 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
10 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to ON. Measure the voltage between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 6 (+) - Engine ground (-): (E57) No. 4 (+) - Engine ground (-)Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.Go to step 11 .
11 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B134) No. 19 - (B134) No. 18: (B134) No. 19 - (B134) No. 28Is the resistance 1 Mohms or more?Go to step 12 .Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.
12 CHECK SENSOR OUTPUT. Connect all connectors. Turn the ignition switch to ON. Read the data of main throttle sensor signal using Subaru Select Monitor. NOTE: For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .Is the voltage 0.81 - 0.87 V?Go to step 13 .Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to THROTTLE BODY .
13 CHECK SENSOR OUTPUT. Read the data of sub throttle sensor signal using Subaru Select Monitor. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .Is the voltage 1.64 - 1.70 V?Go to step 14 .Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to THROTTLE BODY .
14 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and electronic throttle control. Measure the resistance between ECM and electronic throttle control connector. Connector & terminal (B134) No. 2 - (E57) No. 2: (B134) No. 1 - (E57) No. 1Is the resistance less than 1 ohms?Go to step 15 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
15 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 2 (+) - Engine ground (-): (E57) No. 1 (+) - Engine ground (-)Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.Go to step 16 .
16 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 2 - Engine ground: (E57) No. 1 - Engine groundIs the resistance 1 Mohms or more?Go to step 17 .Repair the ground short circuit of harness between ECM and electronic throttle control connector.
17 CHECK ELECTRONIC THROTTLE CONTROL CONNECTOR HARNESS. Measure the resistance between electronic throttle control connectors. Connector & terminal (E57) No. 2 - (E57) No. 1Is the resistance 1 Mohms or more?Go to step 18 .Repair the short circuit of harness between ECM and electronic throttle control connector.
18 CHECK ELECTRONIC THROTTLE CONTROL GROUND CIRCUIT. Measure the resistance between ECM and chassis ground. Connector & terminal (B134) No. 3 - Chassis ground: (B134) No. 4 - Chassis ground: (B134) No. 6 - Chassis ground: (B137) No. 1 - Chassis ground: (B137) No. 3 - Chassis groundIs the resistance less than 5 ohms?Go to step 19 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of coupling connector
19 CHECK ELECTRONIC THROTTLE CONTROL. Measure the resistance between electronic throttle control terminals. Terminals No. 2 - No. 1Is the resistance 50 ohms or less?Go to step 20 .Replace the electronic throttle control. Ref. to THROTTLE BODY .
20 CHECK ELECTRONIC THROTTLE CONTROL. Move the throttle valve to the fully open and fully closed positions with fingers. Check that the valve returns to the specified position when releasing fingers.Does the valve return to the specified position? Standard value: 3 mm (0.12 in) from fully closed positionRepair the poor contact of ECM connector.Replace the electronic throttle control. Ref. to THROTTLE BODY .
NOTE
In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
NOTE
For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .
NOTE
Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Ref. to SUBARU SELECT MONITOR .
NOTE
In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK ELECTRONIC THROTTLE CONTROL RELAY. Turn the ignition switch to OFF. Remove the electronic throttle control relay. Connect the battery to terminals No. 13 and No. 14 of electronic throttle control relay. Measure the resistance between electronic throttle control relay terminals. Terminals No. 15 - No. 16Is the resistance less than 1 ohms?Go to step 2 .Replace the electronic throttle control relay. Ref. to ELECTRONIC THROTTLE CONTROL RELAY .
2 CHECK POWER SUPPLY OF ELECTRONIC THROTTLE CONTROL RELAY. Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 16 (+) - Chassis ground (-)Is the voltage 10 V or more?Go to step 3 .Repair the open or ground short circuit of power supply circuit.
3 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Disconnect the connector from ECM. Turn the ignition switch to ON. Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 14 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the short circuit to power in the harness between ECM and electronic throttle control relay connector.Go to step 4 .
4 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Turn the ignition switch to OFF. Measure the resistance between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 14 - Chassis ground: (B220) No. 15 - Chassis groundIs the resistance 1 Mohms or more?Go to step 5 .Repair the short circuit in harness to ground between ECM and electronic throttle control relay connector.
5 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Measure the resistance between ECM and electronic throttle control relay connector. Connector & terminal (B135) No. 17 - (B220) No. 14: (B135) No. 7 - (B220) No. 15Is the resistance less than 1 ohms?Repair the poor contact of ECM connector.Repair the open circuit in harness between ECM and electronic throttle control relay connector.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK ELECTRONIC THROTTLE CONTROL RELAY. Turn the ignition switch to OFF. Remove the electronic throttle control relay. Measure the resistance between electronic throttle control relay terminals. Terminals No. 5 - No. 16Is the resistance 1 Mohms or more?Go to step 2 .Replace the electronic throttle control relay. Ref. to ELECTRONIC THROTTLE CONTROL RELAY .
2 CHECK SHORT CIRCUIT OF ELECTRONIC THROTTLE CONTROL RELAY POWER SUPPLY. Turn the ignition switch to ON. Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B220) No. 15 (+) - Chassis ground (-)Is the voltage 10 V or more?Repair the short circuit to power in the harness between ECM and electronic throttle control relay connector.Go to step 3 .
3 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM and chassis ground. Connector & terminal (B135) No. 17 - Chassis groundIs the resistance 1 Mohms or more?Repair the poor contact of ECM connector.Repair the short circuit in harness to ground between ECM and electronic throttle control relay connector.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and accelerator pedal position sensor. Measure the resistance of harness between ECM and accelerator pedal position sensor connector. Connector & terminal (B135) No. 23 - (B315) No. 6: (B135) No. 29 - (B315) No. 5Is the resistance less than 1 ohms?Go to step 2 .Repair the open circuit of harness between ECM and accelerator pedal position sensor connector.
2 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Connect the connector to ECM. Measure the resistance between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 5 - Chassis groundIs the resistance less than 5 ohms?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Turn the ignition switch to ON. Measure the voltage between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 6 (+) - Chassis ground (-)Is the voltage 5 V or more?Repair the short circuit to power supply in the harness between the ECM and accelerator pedal position sensor connector.Go to step 4 .
4 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B135) No. 21 - (B135) No. 23Is the resistance 1 Mohms or more?Repair the poor contact of accelerator pedal position sensor connector. Replace the accelerator pedal if defective. Ref. to ACCELERATOR PEDAL .Repair the short circuit to power supply in the harness between the ECM and accelerator pedal position sensor connector.
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and accelerator pedal position sensor. Measure the resistance between ECM and chassis ground. Connector & terminal (B135) No. 22 - Chassis ground: (B135) No. 31 - Chassis groundIs the resistance 1 Mohms or more?Go to step 2 .Repair the short circuit to ground in harness between ECM and accelerator pedal position sensor connector.
2 CHECK SHORT CIRCUIT INSIDE THE ECM. Connect the connector to ECM. Measure the resistance between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 3 - Chassis groundIs the resistance 1 Mohms. or more?Replace the accelerator pedal. Ref. to ACCELERATOR PEDAL .Repair the short circuit to ground in harness between ECM and accelerator pedal position sensor connector. Replace the ECM if defective. Ref. to ENGINE CONTROL MODULE (ECM) .

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and accelerator pedal position sensor. Measure the resistance of harness between ECM and accelerator pedal position sensor connector. Connector & terminal (B135) No. 31 - (B315) No. 3: (B135) No. 30 - (B315) No. 2Is the resistance less than 1 ohms?Go to step 2 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and accelerator pedal position sensor connector. Poor contact of joint connector
2 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Connect the connector to ECM. Measure the resistance between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 2 - Chassis groundIs the resistance less than 1 ohms?Go to step 3 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of joint connector
3 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Turn the ignition switch to ON. Measure the voltage between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 3 (+) - Chassis ground (-)Is the voltage 5 V or more?Repair the short circuit to power supply in the harness between the ECM and accelerator pedal position sensor connector.Go to step 4 .
4 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B135) No. 22 - (B135) No. 31Is the resistance 1 Mohms or more?Repair the poor contact of accelerator pedal position sensor connector. Replace the accelerator pedal if defective. Ref. to ACCELERATOR PEDAL .Repair the short circuit to power supply in the harness between the ECM and accelerator pedal position sensor connector.
NOTE
In this case, repair the following item: Open circuit of harness between ECM and accelerator pedal position sensor connector. Poor contact of joint connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of joint connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM and electronic throttle control. Measure the resistance between ECM and chassis ground. Connector & terminal (B134) No. 19 - Chassis ground: (B134) No. 18 - Chassis ground: (B134) No. 18 - (B136) No. 4: (B134) No. 28 - Chassis groundIs the resistance 1 Mohms or more?Go to step 2 .Repair the ground short circuit of harness between ECM and electronic throttle control connector.
2 CHECK SHORT CIRCUIT INSIDE THE ECM. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 6 - Engine ground: (E57) No. 4 - Engine groundIs the resistance 1 Mohms or more?Go to step 3 .Repair the ground short circuit of harness between ECM and electronic throttle control connector. Replace the ECM if defective. Ref. to ENGINE CONTROL MODULE (ECM) .
3 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Disconnect the connector from ECM. Measure the resistance of harness between ECM and electronic throttle control connector. Connector & terminal (B134) No. 18 - (E57) No. 6: (B134) No. 28 - (E57) No. 4: (B134) No. 29 - (E57) No. 3Is the resistance less than 1 ohms?Go to step 4 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
4 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Connect the connector to ECM. Measure the resistance between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 3 - Engine groundIs the resistance less than 5 ohms?Go to step 5 .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector
5 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to ON. Measure the voltage between electronic throttle control connector and engine ground. Connector & terminal (E57) No. 6 (+) - Engine ground (-): (E57) No. 4 (+) - Engine ground (-)Is the voltage 5 V or more?Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.Go to step 6 .
6 CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B134) No. 19 - (B134) No. 18: (B134) No. 19 - (B134) No. 28Is the resistance 1 Mohms or more?Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to THROTTLE BODY .Repair the short circuit of harness to power supply between ECM and electronic throttle control connector.
NOTE
In this case, repair the following item: Open circuit in harness between ECM and electronic throttle control connector Poor contact of coupling connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of coupling connector

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK ACCELERATOR PEDAL POSITION SENSOR OUTPUT. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal Main accelerator pedal position sensor signal (B135) No. 23 (+) - Chassis ground (-): Sub accelerator pedal position sensor signal (B135) No. 31 (+) - Chassis ground (-)Is the difference between the measured value of main accelerator pedal position sensor signal and the measured value of sub accelerator pedal position sensor signal 0 V?Go to step 3 .Go to step 2 .
2 CHECK ACCELERATOR PEDAL POSITION SENSOR OUTPUT. Measure the voltage between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 6 (+) - Chassis ground (-): (B315) No. 3 (+) - Chassis ground (-)Is the difference between the measured value of main accelerator pedal position sensor signal and the measured value of sub accelerator pedal position sensor signal 0 V?Replace the accelerator pedal. Ref. to ACCELERATOR PEDAL .Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and accelerator pedal position sensor connector. Ground short circuit of harness between ECM and accelerator pedal position sensor connector.
3 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. Measure the resistance of harness between the accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 5 - Chassis ground: (B315) No. 2 - Chassis groundIs the resistance less than 5 ohms?Repair the poor contact of ECM connector.Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and accelerator pedal position sensor connector. Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of joint connector
NOTE
In this case, repair the following item: Open circuit of harness between ECM and accelerator pedal position sensor connector. Ground short circuit of harness between ECM and accelerator pedal position sensor connector.
NOTE
In this case, repair the following item: Open circuit of harness between ECM and accelerator pedal position sensor connector. Open circuit of harness between ECM and engine ground Poor contact of ECM connector Poor contact of joint connector

DIAGNOSTIC PROCEDURE