Engine Controls - Engine (diagnostics) (h4so) Subaru Impreza WRX GH

BASIC DIAGNOSTIC PROCEDURE CHART

CHECK LIST NO. 1

Check the following item when problem has occurred.

Note. Use copies of this article for interviewing customers.

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CHECK LIST NO. 2

Check the following item about the vehicle's state when malfunction indicator light illuminates.

Note. Use copies of this article for interviewing customers.

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1. Airbag system wiring harness is routed near the ECM, main relay and fuel pump relay. CAUTION: All airbag system wiring harnesses and connectors are yellow. Do not use the electrical test equipment on these circuits. Be careful not to damage the airbag system wiring harness when servicing the ECM, TCM, main relay and fuel pump relay.
2. Never connect the battery in reverse polarity. Doing so will damage the ECM instantly, and the fuel injector and other parts will also be damaged.
3. Do not disconnect the battery terminals while the engine is running. A large counter electromotive force will be generated in the generator, and this voltage may damage electronic parts such as ECM etc.
4. Before disconnecting the connectors of each sensor and ECM, be sure to turn the ignition switch to OFF. Perform the Clear Memory Mode after connecting the connectors. CLEAR MEMORY MODE. >
5. Measure the voltage or resistance of individual sensor or all electrical control modules using a tapered pin with a diameter of less than 0.6 mm (0.024 in). Do not insert the pin 4 mm (0.16 in) or more into the part. CAUTION: When replacing the ECM, be careful not to use the wrong spec. ECM to avoid any damage on the fuel injection system. NOTE: When replacing the ECM of the models with Immobilizer, immobilizer system must be registered. To do so, all ignition keys and ID cards need to be prepared. Refer to the "IMMOBILIZER TEACHING OPERATION MANUAL".
6. Take care not to allow water to get into the connectors when servicing or washing the vehicle in rainy weather. Avoid exposure to water even if the connectors are waterproof.
7. Use ECM mounting stud bolts at the body side grounding point when measuring voltage and resistance inside the passenger compartment.
8. Use the engine ground terminal or engine assembly for the grounding point to chassis when measuring the voltage and resistance in engine compartment.
9. Every MFI-related part is a precision part. Do not drop them.
10. Observe the following cautions when installing a radio in MFI equipped models. CAUTION: The antenna must be kept as far apart as possible from control module. (ECM is installed under the passenger's side floor mat.) The antenna feeder must be placed as far apart as possible from the ECM and MFI harness. Carefully adjust the antenna for correct matching. When mounting a large power type radio, pay special attention to the three items mentioned above. Incorrect installation of the radio may affect the operation of ECM.
11. When disconnecting the fuel hose, release the fuel pressure. RELEASING OF FUEL PRESSURE , PROCEDURE, Fuel . >
12. For the model with ABS, the ABS warning light may illuminate when performing driving test with jacked-up or lifted-up condition, but this is not a system malfunction. The reason for this is the speed difference between the front and rear wheels. After diagnosis of engine control system, perform the ABS memory clear procedure of self-diagnosis function.

INSPECTION

Before performing diagnostics, check the following item which might affect engine problems.

BATTERY

1. Measure the battery voltage and specific gravity of the electrolyte. Standard voltage: 12 V Specific gravity: 1.260 or more
2. Check the condition of the main and other fuses, and harnesses and connectors. Also check for proper grounding.

ENGINE GROUND

Check if the engine ground terminal is properly connected to engine.

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GENERAL DESCRIPTION

1. The on-board diagnostic (OBD) system detects and indicates a fault in various inputs and outputs of the complex electronic throttle control. Malfunction indicator light in the combination meter indicates occurrence of a fault or trouble.
2. Further, against such a failure or sensors as may disable the drive, the fail-safe function is provided to ensure the minimal driveability.
3. The OBD system incorporated with the vehicles within this type of engine complies with OBD-II regulations. The OBD system monitors the components and the system malfunction listed in "Engine Section" which affects on emissions.
4. When the system decides that a malfunction occurs, malfunction indicator light illuminates. At the same time of the malfunction indicator light illumination or blinking, a DTC and a freeze frame engine conditions are stored into on-board computer.
5. The OBD system stores freeze frame engine condition data (engine load, engine coolant temperature, fuel trim, engine speed and vehicle speed, etc.) into on-board computer first when it detects a malfunction.
6. If the OBD system detects malfunctions such as the fault of fuel trim or misfire, the OBD system first stores freeze frame engine conditions about the fuel trim or misfire.
7. When the malfunction does not occur again for three consecutive driving cycles, malfunction indicator light is turned off, but DTC remains at onboard computer.
8. When troubleshooting the vehicle which complies with OBD-II regulations, connect the Subaru Select Monitor or general scan tool to the vehicle.

ENGINE AND EMISSION CONTROL SYSTEM

1. The Multipoint Fuel Injection (MFI) system is a system that supplies the optimum air-fuel mixture to the engine for all the various operating conditions through the use of the latest electronic technology.

With this system, the fuel which is pressurized at a constant pressure is injected into the intake air passage of the cylinder head. The injection quantity of fuel is controlled by an intermittent injection system, where the electro-magnetic injection valve (fuel injector) opens for a short period of time depending on the quantity of air required for one cycle of operation. In actual operation, the injection quantity is determined by the duration of an electric pulse applied to the fuel injector and this permits simple, yet highly precise metering of the fuel.

1. Furthermore, all operating conditions of the engine are converted into electronic signals, and this enables additional system features with greatly improved adaptability, making it easier to add compensation features. The MFI system also has the following features

1. Reduced emission of harmful exhaust gases.
2. Reduction in fuel consumption
3. Increased engine output.
4. Superior acceleration and deceleration.
5. Superior startability and warm-up performance in cold weather since compensation is made for engine coolant and intake air temperature.

PREPARATION TOOL

PREPARATION TOOL REFERENCE CHART ILLUSTRATION TOOL NUMBER DESCRIPTION REMARKS 1B021XU0 SUBARU SELECT MONITOR III KIT Used for troubleshooting the electrical system. 499987500 CRANKSHAFT SOCKET Used for rotating crankshaft

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1. Control module

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1. Sensor

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1. Solenoid valve, actuator, emission control system parts and ignition system parts

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ENGINE CONNECTOR TERMINALS REFERENCE CHART

WAVEFORM REFERENCE CHART Input/output name Measuring condition Waveform 1. Crankshaft position sensor During idling 2. Camshaft position sensor During idling

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ELECTRICAL SPECIFICATION

ENGINE ELECTRICAL SPECIFICATION

Measuring condition

1. After engine is warmed-up.
2. Set the select lever in "P" range or "N" range, or the shift lever in neutral.
3. Turn the A/C to OFF.
4. Turn all the accessory switches to OFF.

NOTE

This connector is used for Subaru Select Monitor.

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TERMINAL REFERENCE CHART

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1. Prepare a scan tool (general scan tool) required by SAE J1978.
2. Connect the general scan tool to data link connector located in the lower portion of the instrument panel (on the driver's side).
3. Using the general scan tool, call up DTC and freeze frame data. General scan tool functions consist of: MODE $01: Current powertrain diagnostic data MODE $02: Powertrain freeze frame data MODE $03: Emission-related powertrain DTC MODE $04: Clear/Reset emission-related diagnostic information MODE $06: Request on-board monitoring test results for intermittently monitored systems MODE $07: Request on-board monitoring test results for continuously monitored systems MODE $09: Request vehicle information Read out the data according to repair procedures. (For detailed operation procedure, refer to the general scan tool instruction manual.) NOTE: For details concerning DTC, Refer to " «LIST OF DIAGNOSTIC TROUBLE CODE (DTC)»(/subaru/impreza-wrx/gh-2007-2010/remont/testing-diagnostics/#engine-controls-engine-diagnostics-h4so) ". LIST OF DIAGNOSTIC TROUBLE CODE (DTC). >

MODE $01: (CURRENT POWERTRAIN DIAGNOSTIC DATA)

Refer to data denoting the current operating condition of analog input/output, digital input/output or the powertrain system.

A list of the support data and PID (Parameter Identification) codes are shown in the following table.

CURRENT POWERTRAIN DIAGNOSTIC DATA REFERENCE CHART

Note. Refer to general scan tool manufacturer's instruction manual to access generic OBD-II PIDs (MODE $01).

MODE $02 (POWERTRAIN FREEZE FRAME DATA)

Refer to data denoting the operating condition when trouble is detected by on-board diagnosis system. A list of the support data and PID (Parameter Identification) codes are shown in the following table.

POWERTRAIN FREEZE FRAME DATA REFERENCE CHART

Note. Refer to general scan tool manufacturer's instruction manual to access freeze frame data (MODE $02).

MODE $03 (EMISSION-RELATED POWERTRAIN DTC)

Refer to " LIST OF DIAGNOSTIC TROUBLE CODE (DTC) " for information about data denoting emission-related powertrain DTC. LIST OF DIAGNOSTIC TROUBLE CODE (DTC). >

MODE $04 (CLEAR/RESET EMISSION-RELATED DIAGNOSTIC INFORMATION)

Refer to the mode used to clear or reset emission-related diagnostic information (OBD-II trouble diagnostic information).

Note. Refer to general scan tool manufacturer's instruction manual to clear the emission-related diagnostic information (MODE $04).

MODE $06

Refer to test value of troubleshooting and data of test limit indicated on the support data bit sequence table. A list of the support data is shown in the following table.

POWERTRAIN FREEZE FRAME DATA REFERENCE CHART

MODE $07

Refer to the data of DTC (pending code) for troubleshooting result about emission in the first time.

MODE $09

Refer to data of vehicle specification (V.I.N., calibration ID, diagnosis frequency etc.).

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1. Prepare the Subaru Select Monitor kit. PREPARATION TOOL, General Description. >
2. Prepare the personal computer which has been installed the Subaru Select Monitor.
3. Connect the USB cable between SDI (Subaru Diagnosis Interface) and USB port on the personal computer (dedicated port for the Subaru Select Monitor). NOTE: The dedicated port for the Subaru Select Monitor means the USB port which was used to install the Subaru Select Monitor.
4. Connect the diagnosis cable to the SDI.
5. Connect the SDI to data link connector located in the lower portion of the instrument panel (on the driver's side). CAUTION: Do not connect the scan tools except for Subaru Select Monitor and general scan tool.
6. Start up the personal computer.
7. Turn the ignition switch to ON (engine OFF), and run the "PC application for Subaru Select Monitor".
8. Call up DTC and data, then record them.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

READ DIAGNOSTIC TROUBLE CODE (DTC) FOR ENGINE (NORMAL MODE)

Refer to " READ DIAGNOSTIC TROUBLE CODE " for information about how to display a DTC. READ DIAGNOSTIC TROUBLE CODE (DTC). >

READ DIAGNOSTIC TROUBLE CODE (DTC) FOR ENGINE (OBD MODE)

Refer to " READ DIAGNOSTIC TROUBLE CODE " for information about how to display a DTC. READ DIAGNOSTIC TROUBLE CODE (DTC). >

READ CURRENT DATA FOR ENGINE (NORMAL MODE)

1. On the «Main Menu» display screen, select the {Each System Check}.
2. On the «System Selection Menu» display screen, select the {Engine Control System}.
3. Click the [OK] button after the information of engine type has been displayed.
4. On the «Engine Diagnosis» display screen, select the {Current Data Display & Save}.
5. On the «Current Data Display & Save» display screen, select the {Normal Measurement}.
6. Using the scroll key, scroll the display screen up or down until the desired data is shown.

1. A list of the support data is shown in the following table.

CURRENT DATA FOR ENGINE (NORMAL MODE)

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

READ CURRENT DATA FOR ENGINE (OBD MODE)

1. On the «Main Menu» display screen, select the {Each System Check}.
2. On the «System Selection Menu» display screen, select the {Engine Control System}.
3. Click the [OK] button after the information of engine type has been displayed.
4. On the «Engine Diagnosis» display screen, select the {OBD System}.
5. On the «OBD Menu» display screen, select the {Current Data Display & Save}.
6. On the «Current Data Display & Save» display screen, select the {All Data Display}.
7. Using the scroll key, scroll the display screen up or down until the desired data is shown.

1. A list of the support data is shown in the following table.

CURRENT DATA FOR ENGINE (OBD MODE)

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

READ FREEZE FRAME DATA FOR ENGINE (OBD MODE)

1. On the «Main Menu» display screen, select the {Each System Check}.
2. On the «System Selection Menu» display screen, select the {Engine Control System}.
3. Click the [OK] button after the information of engine type has been displayed.
4. On the «Engine Diagnosis» display screen, select the {OBD System}.
5. On the «OBD Menu» display screen, select the {Freeze Frame Data Display}.

1. A list of the support data is shown in the following table.

FREEZE FRAME DATA FOR ENGINE (OBD MODE)

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

V.I.N REGISTRATION

1. On the «Main Menu» display screen, select the {Each System Check}.
2. On the «System Selection Menu» display screen, select the {Engine Control System}.
3. Click the [OK] button after the information of engine type has been displayed.
4. On the «Engine Diagnosis» display screen, select the {V.I.N. Registration}.
5. Perform the procedures shown on the display screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

SUBARU SELECT MONITOR (NORMAL MODE)

1. On the «Main Menu» display screen, select the {Each System Check}.
2. On the «System Selection Menu» display screen, select the {Engine Control System}.
3. Click the [OK] button after the information of engine type has been displayed.
4. On the «Engine Diagnosis» display screen, select the {Diagnostic Code(s) Display}.
5. On the «Diagnostic Code(s) Display» screen, select the {Temporary Code} or {Memory Code}.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor. For details concerning DTC, refer to " LIST OF DIAGNOSTIC TROUBLE CODE (DTC) ". LIST OF DIAGNOSTIC TROUBLE CODE (DTC). >

SUBARU SELECT MONITOR (OBD MODE)

1. On the «Main Menu» display screen, select the {Each System Check}.
2. On the «System Selection Menu» display screen, select the {Engine Control System}.
3. Click the [OK] button after the information of engine type has been displayed.
4. On the «Engine Diagnosis» display screen, select the {OBD System}.
5. On the «OBD Menu» display screen, select the {Diagnostic Code(s) Display}.
6. Make sure DTC is shown on the screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor. For details concerning DTC, refer to " LIST OF DIAGNOSTIC TROUBLE CODE (DTC) ". LIST OF DIAGNOSTIC TROUBLE CODE (DTC). >

GENERAL SCAN TOOL

Refer to data denoting emission-related powertrain DTC.

For details concerning DTC, refer to " LIST OF DIAGNOSTIC TROUBLE CODE (DTC) ". LIST OF DIAGNOSTIC TROUBLE CODE (DTC). >

Note. Refer to general scan tool manufacturer's instruction manual to access powertrain DTC (MODE $03).

PROCEDURE

Perform the diagnosis shown in the following DTC table.

When performing the diagnosis not listed in "List of Diagnostic Trouble Code (DTC)", refer to the item on the drive cycle. DRIVE CYCLE. >

LIST OF DIAGNOSTIC TROUBLE CODE (DTC)

PREPARATION FOR THE INSPECTION MODE

1. Check that the battery voltage is 12 V or more and fuel remains approx. half [20 - 40 l (5.3 - 10.6 US gal, 4.4 - 8.8 lmp gal)].
2. Lift up the vehicle using a garage jack and place it on rigid racks, or drive the vehicle onto free rollers.

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1. After clearing the memory, check for any remaining unresolved trouble data. CLEAR MEMORY MODE. >
2. Warm-up the engine.
3. Prepare the Subaru Select Monitor kit. PREPARATION TOOL, General Description. >
4. Prepare the personal computer which has been installed the Subaru Select Monitor.
5. Connect the USB cable between SDI (Subaru Diagnosis Interface) and USB port on the personal computer (dedicated port for the Subaru Select Monitor). NOTE: The dedicated port for the Subaru Select Monitor means the USB port which was used to install the Subaru Select Monitor.
6. Connect the diagnosis cable to the SDI.
7. Connect the delivery (test) mode connector (A) located under the glove box.
8. Connect the SDI to data link connector located in the lower portion of the instrument panel (on the driver's side). CAUTION: Do not connect the scan tools except for Subaru Select Monitor and general scan tool.
9. Start up the personal computer.
10. Turn the ignition switch to ON (engine OFF), and run the "PC application for Subaru Select Monitor".
11. On the «Main Menu» display screen, select the {Each System Check}.
12. On the «System Selection Menu» display screen, select the {Engine Control System}.
13. Click the [OK] button after the information of engine type has been displayed.
14. On the «Engine Diagnosis» display screen, select the {D Check}.
15. When the «Perform Inspection (Dealer Check) Mode» is shown on the screen, click the [Next] button.
16. Perform subsequent procedures as instructed on the display screen.

1. If trouble still remains in the memory, the corresponding DTC appears on the display screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor. For details concerning DTC, refer to " LIST OF DIAGNOSTIC TROUBLE CODE (DTC) ". LIST OF DIAGNOSTIC TROUBLE CODE (DTC). > Release the parking brake. The speed difference between front and rear wheels may illuminate the ABS warning light, but this does not indicate a malfunction. When engine control diagnosis is finished, perform the ABS memory clearance procedure of self-diagnosis function. CLEAR MEMORY MODE . >

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1. After performing the diagnostics and clearing the memory, check for any remaining unresolved trouble data. CLEAR MEMORY MODE. >
2. Warm-up the engine.
3. Connect the delivery (test) mode connector (A) located under the glove box.
4. Connect the general scan tool to data link connector located in the lower portion of the instrument panel (on the driver's side). CAUTION: Do not connect the scan tools except for Subaru Select Monitor and general scan tool.
5. Start the engine. NOTE: Ensure the selector lever is placed in "P" range before starting. (AT model) Depress the clutch pedal when starting engine. (MT model)
6. Turn the neutral position switch to ON using select lever or shift lever.
7. Depress the brake pedal to turn the brake switch ON. (AT model)
8. Keep the engine speed in 2,500 - 3,000 rpm range for 40 seconds.
9. Place the select lever or shift lever in D position (AT model) or 1st gear (MT model) and drive the vehicle at 5 to 10 km/h (3 to 6 MPH). NOTE: For AWD model, release the parking brake. The speed difference between front and rear wheels may illuminate the ABS warning light, but this indicates no malfunctions. When engine control diagnosis is finished, perform the ABS memory clearance procedure of self-diagnosis system. CLEAR MEMORY MODE . >
10. Using the general scan tool, check DTC and record the result(s).

Note. For detailed operation procedures, refer to the general scan tool operation manual. For details concerning DTC, refer to " LIST OF DIAGNOSTIC TROUBLE CODE (DTC) ". LIST OF DIAGNOSTIC TROUBLE CODE (DTC). >

For the troubleshooting, there are driving patterns described below. Driving in the specified pattern allows to diagnose malfunctioning items listed below. After the repair of the following trouble items, be sure to drive the vehicle with the specified drive patterns to check whether the function is resumed correctly.

PREPARATION FOR DRIVE CYCLE

1. Check that the battery voltage is 12 V or more and fuel remains approx. half [20 - 40 l (5.3 - 10.6 US gal, 4.4 - 8.8 lmp gal)].
2. After performing the diagnostics and clearing the memory, check for any remaining unresolved trouble data. CLEAR MEMORY MODE. >
3. Disconnect the delivery (test) mode connector.

Note. Perform the diagnosis after warming up the engine except when the engine coolant temperature at starting is specified. Perform the diagnosis twice if the DTC marked with *. After completing the first diagnosis, stop the engine and perform second diagnosis in same condition.

DRIVE CYCLE A - DRIVE THE VEHICLE WITH 80 KM/H (50 MPH) FOR 20 MINUTES, AND THEN IDLE THE ENGINE FOR A MINUTE

DRIVE CYCLE CONDITION CHART

DRIVE CYCLE B - 10 MINUTES IDLING

Note. Drive the vehicle at 10 km/h (6 MPH) or more before diagnosis.

DRIVE CYCLE CONDITION CHART

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VEHICLE DRIVE PATTERNS CHART

DRIVE CYCLED

1. DRIFT DIAGNOSIS Check that the engine coolant temperature at engine start is less than 30°C (86°F). Make sure that fuel remains 10 l (2.6 US gal, 2.2 lmp gal) or more and the battery voltage is 10.9 V or more. Start the engine, and check that the engine coolant temperature increases by 10°C (50°F) or more, and reaches 75°C (167°F) or more, when the engine is warmed up. Idle the engine for 120 seconds or more in the condition of step 3.
2. STUCK DIAGNOSIS Make sure that the battery voltage is 10.9 V or more. Perform the Clear Memory Mode. CLEAR MEMORY MODE. > Drive the vehicle for the distance equal to the fuel of 50 l (13.2 US gal, 11 lmp gal). NOTE: It is acceptable to drive the vehicle intermittently. Do not disconnect the battery terminals while diagnosing. (Data will be cleared by disconnecting the battery terminals.) DRIVE CYCLED CONDITION CHART DTC Item Condition P0181 Fuel Temperature Sensor "A" Circuit Range/Performance

DRIVE CYCLE E

1. Make sure that the battery voltage is 10.9 V or more.
2. Perform the Clear Memory Mode. CLEAR MEMORY MODE. >
3. Drive the vehicle for the distance equal to the fuel of 30 l (7.9 US gal, 6.6 lmp gal).

Note. It is acceptable to drive the vehicle intermittently. Do not disconnect the battery terminals while diagnosing. (Data will be cleared by disconnecting the battery terminals.)

DRIVE CYCLED CONDITION CHART

DRIVE CYCLE F

1. Check that the engine coolant temperature at engine start is less than 30°C (86°F).
2. Start the engine, and warm it up until engine coolant temperature increases over 95°C (203°F).
3. After the engine has reached the state of procedure 2), idle the engine for 10 minutes or more.

Note. Do not disconnect the battery terminals while diagnosing. (Data will be cleared by disconnecting the battery terminals.)

DRIVE CYCLED CONDITION CHART

DRIVE CYCLE H

1. Perform the Clear Memory Mode. CLEAR MEMORY MODE. >
2. With the ignition switch ON, read the engine coolant temperature, intake air temperature and fuel temperature. READ CURRENT DATA FOR ENGINE (NORMAL MODE), OPERATION, Subaru Select Monitor. >
3. If the values from step 2) satisfy the following two conditions, start the engine. Condition: |Engine coolant temperature - Intake air temperature | < or = 5°C (41 °F) |Engine coolant temperature - Fuel temperature | < or = 2°C (36°F) NOTE: If the conditions are not satisfied, turn the ignition switch to OFF and wait until the parameters are satisfied. Start AT vehicles in the P range, and MT vehicles in the N position.
4. Idle the engine for 1 minute under the conditions in step 3).

DRIVE CYCLED CONDITION CHART

1. On the «Main Menu» display screen, select the {Each System Check}.
2. On the «System Selection Menu» display screen, select the {Engine Control System}.
3. Click the [OK] button after the information of engine type has been displayed.
4. On the «Engine Diagnosis» display screen, select the {Clear Memory}.
5. When the "Clear Memory?" is shown on the screen, click the [Yes] button.
6. When "Done" and "Turn ignition switch to OFF" is shown on the display screen, turn the ignition switch to OFF.

Note. Initial diagnosis of electronic throttle control is performed after memory clearance. Therefore, start the engine 10 seconds or more after turning the ignition switch to ON. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

1. On the «Main Menu» display screen, select the {Each System Check}.
2. On the «System Selection Menu» display screen, select the {Engine Control System}.
3. Click the [OK] button after the information of engine type has been displayed.
4. On the «Engine Diagnosis» display screen, select the {OBD System}.
5. On the «OBD Menu» display screen, select the {Clear Diagnostic Code?}.
6. When the "Clear Diagnostic Code?" is shown on the screen, click the [Yes] button.
7. When "Done" and "Turn ignition switch to OFF" is shown on the display screen, turn the ignition switch to OFF.

Note. Initial diagnosis of electronic throttle control is performed after memory clearance. Therefore, start the engine 10 seconds or more after turning the ignition switch to ON. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

For clear memory procedures using the general scan tool, refer to "General Scan Tool Instruction Manual".

Note. Initial diagnosis of electronic throttle control is performed after memory clearance. For this reason, start the engine after 10 seconds or more have elapsed since the ignition switch was turned to ON.

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1. Prepare the Subaru Select Monitor kit. PREPARATION TOOL, General Description. >
2. Prepare the personal computer which has been installed the Subaru Select Monitor.
3. Connect the USB cable between SDI (Subaru Diagnosis Interface) and USB port on the personal computer (dedicated port for the Subaru Select Monitor). NOTE: The dedicated port for the Subaru Select Monitor means the USB port which was used to install the Subaru Select Monitor.
4. Connect the diagnosis cable to the SDI.
5. Connect the delivery (test) mode connector (A) located under the glove box.
6. Connect the SDI to data link connector located in the lower portion of the instrument panel (on the driver's side). CAUTION: Do not connect the scan tools except for Subaru Select Monitor and general scan tool.
7. Start up the personal computer.
8. Turn the ignition switch to ON (engine OFF), and run the "PC application for Subaru Select Monitor".
9. On the «Main Menu» display screen, select the {Each System Check}.
10. On the «System Selection Menu» display screen, select the {Engine Control System}.
11. Click the [OK] button after the information of engine type has been displayed.
12. On the «Engine Diagnosis» display screen, select the {System Operation Check Mode}.
13. On the «System Operation Check Mode» display screen, select the {Actuator ON/OFF Operation}.
14. Select the desired compulsory actuator on the «Actuator ON/OFF Operation» display screen and click the [Next] button.
15. Clicking the [End] button completes the compulsory valve operation check mode. The display will then return to the «Actuator ON/OFF Operation» screen.

1. A list of the support data is shown in the following table.

LIST OF SUPPORT DATA

Note. The following parts will be displayed but not functional.

DISPLAY REFERENCE CHART

1. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

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1. Prepare the Subaru Select Monitor kit. PREPARATION TOOL, General Description. >
2. Prepare the personal computer which has been installed the Subaru Select Monitor.
3. Connect the USB cable between SDI (Subaru Diagnosis Interface) and USB port on the personal computer (dedicated port for the Subaru Select Monitor). NOTE: The dedicated port for the Subaru Select Monitor means the USB port which was used to install the Subaru Select Monitor.
4. Connect the diagnosis cable to the SDI.
5. Connect the SDI to data link connector located in the lower portion of the instrument panel (on the driver's side). CAUTION: Do not connect the scan tools except for Subaru Select Monitor and general scan tool.
6. Start up the personal computer.
7. Turn the ignition switch to ON (engine OFF), and run the "PC application for Subaru Select Monitor".
8. On the «Main Menu» display screen, select the {Each System Check}.
9. On the «System Selection Menu» display screen, select the {Engine Control System}.
10. Click the [OK] button after the information of engine type has been displayed.
11. On the «Engine Diagnosis» display screen, select the {System Operation Check Mode}.
12. The following items will be displayed on screen.

DISPLAY REFERENCE CHART

FUEL PUMP CONTROL (OFF DRIVE)

1. On the «System Operation Check Mode» display, select the {Fuel Pump Control}.
2. On the «Fuel Pump Control» display screen, select the {OFF Operation}.
3. On the «Start the Engine» display screen, start the engine and click the [OK] button.
4. Click the [Cancel] button to end the OFF drive. The screen will return to the «Fuel Pump Control» screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

FUEL PUMP CONTROL (ON/OFF DRIVE)

1. On the «System Operation Check Mode» display, select the {Fuel Pump Control}.
2. On the «Fuel Pump Control» display screen, select the {ON/OFF Operation}.
3. On the «Turn Ignition Switch ON with Engine Stalled» display screen, turn the ignition switch to ON and click the [OK] button.
4. Click the [Cancel] button to end the ON/OFF drive. The screen will return to the «Fuel Pump Control» screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

IDLING IGNITION TIMING FIXED

1. On the «System Operation Check Mode» display screen, select the {Idling Ignition Timing Fixed}.
2. On the «Start the Engine» display screen, start the engine and click the [OK] button.
3. Click the [Cancel] button to end the idle ignition timing fixed. The screen will return to the « «SYSTEM OPERATION CHECK MODE»(/subaru/impreza-wrx/gh-2007-2010/remont/testing-diagnostics/#engine-controls-engine-diagnostics-h4so) » screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

IDLE SPEED CONTROL

1. On the «System Operation Check Mode» display screen, select the {Idle Speed Control}.
2. On the «Start the Engine» display screen, start the engine and click the [OK] button.
3. In the «Idle Engine Speed Control» screen, click the [↑] button or the [↓] button to change the setting values, then click the [OK] button. Setting is possible in a range between 500 rpm - 2,000 rpm, in increments of 50 rpm. However, the engine speed that can actually be controlled will vary depending on the vehicle.
4. Click the [Cancel] button to end the idle speed control. The screen will return to the « «SYSTEM OPERATION CHECK MODE»(/subaru/impreza-wrx/gh-2007-2010/remont/testing-diagnostics/#engine-controls-engine-diagnostics-h4so) » screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

INJECTOR CONTROL. (INJECTION STOP MODE)

1. On the «System Operation Check Mode» display, select the {Injector Control}.
2. On the «Injector Control» display screen, select the {Injection Stop Mode}.
3. Select the desired injector number on the «Injection Stop Mode» screen, and click the [OK] button.
4. On the «Start the Engine» display screen, start the engine and click the [OK] button.
5. Click the [Cancel] button to return the «Injection Stop Mode» display screen.
6. On the «Injection Stop Mode» display screen, click the [Return] button to end the «Injection Stop Mode». The screen will return to the «Injector Control» screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

INJECTOR CONTROL. (INJECTION QUANTITY CONTROL)

1. On the «System Operation Check Mode» display, select the {Injector Control}.
2. On the «Injector Control» display screen, select the {Injection Quantity Control}.
3. On the «Start the Engine» display screen, start the engine and click the [OK] button.
4. In the «Injection Quantity Control» screen, click the [↑] button or the [↓] button to change the setting values, then click the [OK] button. Setting is possible in a range between 0 - 20%, in increments of 1%.
5. Click the [Cancel] button to end the injection quantity control. The screen will return to the «Injector Control» screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

EGR VALVE CONTROL

1. On the «System Operation Check Mode» display, select the {EGR Valve Control}.
2. On the «Start the Engine» display screen, start the engine and click the [OK] button.
3. In the «EGR Valve Control» screen, click the [↑] button or the [↓] button to change the setting values, then click the [OK] button. Setting is possible in 1 STEP increments. However, the number of STEPs that can actually be controlled will vary depending on the vehicle.
4. Click the [Cancel] button to end the EGR valve control. The screen will return to the « «SYSTEM OPERATION CHECK MODE»(/subaru/impreza-wrx/gh-2007-2010/remont/testing-diagnostics/#engine-controls-engine-diagnostics-h4so) » screen.

Note. For detailed operation procedure, refer to the PC application help for Subaru Select Monitor.

MALFUNCTION INDICATOR LIGHT REFERENCE

Scheme 45

Scheme 46

Scheme 47

1. When the ignition switch is turned to ON (engine OFF), the malfunction indicator light (A) in the combination meter illuminates. NOTE: If the malfunction indicator light does not illuminate, perform diagnostics of the malfunction indicator light circuit or the combination meter circuit. MALFUNCTION INDICATOR LIGHT DOES NOT COME ON, Malfunction Indicator Light. >
2. After starting the engine, the malfunction indicator light goes out. If it does not go off, either the engine or emission control system has malfunction.
3. Turn the ignition switch to OFF and connect the delivery (test) mode connector. When the ignition switch is turned to ON (engine OFF), the malfunction indicator light illuminates. After the engine starts, malfunction indicator light blinks in a cycle of 0.5 Hz. (During diagnosis) Malfunction indicator light blinks at a cycle of 3 Hz after diagnosis if there is no trouble. Malfunction indicator light illuminates if faulty.

DIAGNOSIS

The malfunction indicator light circuit is open or shorted.

TROUBLE SYMPTOM

When the ignition switch is turned to ON (engine OFF), malfunction indicator light does not come on.

Scheme 48

DIAGNOSIS PROCEDURE

The malfunction indicator light circuit is shorted.

Although malfunction indicator light illuminates when the engine runs, DTC is not shown on the Subaru Select Monitor display.

Scheme 49

DIAGNOSIS PROCEDURE

1. The malfunction indicator light circuit is open or shorted.
2. The delivery (test) mode connector circuit is open.

Malfunction indicator light does not blink during Inspection Mode.

Scheme 50

DIAGNOSIS PROCEDURE

The delivery (test) mode connector circuit is shorted.

Malfunction indicator light blinks when delivery (test) mode connector is not connected.

Scheme 51

DIAGNOSIS PROCEDURE

DIAGNOSTICS FOR ENGINE STARTING FAILURE REFERENCE

STARTER MOTOR CIRCUIT

Scheme 52

DIAGNOSIS PROCEDURE

CHECK POWER SUPPLY AND GROUND LINE OF ENGINE CONTROL MODULE (ECM)

Scheme 53

DIAGNOSIS PROCEDURE

IGNITION CONTROL SYSTEM

Scheme 54

DIAGNOSIS PROCEDURE

FUEL PUMP CIRCUIT

Scheme 55

DIAGNOSIS PROCEDURE

FUEL INJECTOR CIRCUIT

Scheme 56

DIAGNOSIS PROCEDURE

LIST

LIST OF DIAGNOSTIC TROUBLE CODE

DTC DETECTING CONDITION

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0026 INTAKE VALVE CONTROL SOLENOID CIRCUIT RANGE/PERFORMANCE (BANK 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Improper idling

Scheme 57

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0028 INTAKE VALVE CONTROL SOLENOID CIRCUIT RANGE/PERFORMANCE (BANK 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Improper idling

Scheme 58

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0030 HO2S HEATER CONTROL CIRCUIT (BANK 1 SENSOR 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 59

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0031 HO2S HEATER CONTROL CIRCUIT LOW (BANK 1 SENSOR 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 60

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0032 HO2S HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 61

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0037 HO2S HEATER CONTROL CIRCUIT LOW (BANK 1 SENSOR 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 62

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0038 HO2S HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 63

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0068 MAP/MAF - THROTTLE POSITION CORRELATION , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 64

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0076 INTAKE VALVE CONTROL SOLENOID CIRCUIT LOW (BANK 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Improper idling

Scheme 65

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0077 INTAKE VALVE CONTROL SOLENOID CIRCUIT HIGH (BANK 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Improper idling

Scheme 66

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0082 INTAKE VALVE CONTROL SOLENOID CIRCUIT LOW (BANK 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Improper idling

Scheme 67

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0083 INTAKE VALVE CONTROL SOLENOID CIRCUIT HIGH (BANK 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Improper idling

Scheme 68

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0101 MASS OR VOLUME AIR FLOW CIRCUIT RANGE/PERFORMANCE , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Engine stalls.
3. Poor driving performance

Scheme 69

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0102 MASS OR VOLUME AIR FLOW CIRCUIT LOW INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Engine stalls.
3. Poor driving performance

Scheme 70

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT HIGH INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Engine stalls.
3. Poor driving performance

Scheme 71

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0107 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE CIRCUIT LOW INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 72

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0108 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE CIRCUIT HIGH INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 73

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0111 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT RANGE/PERFORMANCE , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Poor driving performance

Scheme 74

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0112 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT LOW , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Poor driving performance

Scheme 75

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0113 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT HIGH , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Poor driving performance

Scheme 76

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0117 ENGINE COOLANT TEMPERATURE CIRCUIT LOW , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Hard to start
2. Improper idling
3. Poor driving performance

Scheme 77

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0118 ENGINE COOLANT TEMPERATURE CIRCUIT HIGH , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Hard to start
2. Improper idling
3. Poor driving performance

Scheme 78

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0122 THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT LOW , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Engine stalls.
3. Poor driving performance

Scheme 79

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0123 THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT HIGH , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Engine stalls.
3. Poor driving performance

Scheme 80

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0125 INSUFFICIENT COOLANT TEMPERATURE FOR CLOSED LOOP FUEL CONTROL , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Engine does not return to idle.

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0126 INSUFFICIENT ENGINE COOLANT TEMPERATURE FOR STABLE OPERATION , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Hard to start
2. Improper idling
3. Poor driving performance

Scheme 81

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0128 COOLANT THERMOSTAT (ENGINE COOLANT TEMPERATURE BELOW THERMOSTAT REGULATING TEMPERATURE) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Thermostat remains open.

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0131 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 82

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0132 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 83

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0133 O2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 84

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0134 O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SENSOR 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 85

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0137 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 86

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0138 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 87

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0139 O2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 88

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0140 O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SENSOR 2) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 89

DIAGNOSIS PROCEDURE

DTC P0171 SYSTEM TOO LEAN (BANK 1)

Refer to DTC P0172 for diagnostic procedure. DTC P0172 SYSTEM TOO RICH (BANK 1), Diagnostic Procedure with Diagnostic Trouble Code (DTC). >

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0172 SYSTEM TOO RICH (BANK 1) , Diagnostic Trouble Code (DTC) Detecting Criteria . >

1. Improper idling
2. Engine stalls.
3. Poor driving performance

DIAGNOSIS PROCEDURE

1. Detected when two consecutive driving cycles with fault occur.
2. GENERAL DESCRIPTION DTC P0181 FUEL TEMPERATURE SENSOR "A" CIRCUIT RANGE/PERFORMANCE , Diagnostic Trouble Code (DTC) Detecting Criteria . >

Scheme 90

DIAGNOSIS PROCEDURE

1. Immediately at fault recognition
2. GENERAL DESCRIPTION DTC P0182 FUEL TEMPERATURE SENSOR "A" CIRCUIT LOW INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria . >