Engine Controls - Tests W/codes: Other Subaru Impreza GC/GF

HARD FAILURES

Hard failures cause CHECK ENGINE light to glow and remain on until problem is repaired. If light comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined using diagnostic (code) charts. If a sensor fails, control unit will use a substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, vehicle runs but driveability will not be optimum.

INTERMITTENT FAILURES

Intermittent failures may cause CHECK ENGINE light to flicker or glow and go out after intermittent fault goes away. However, corresponding trouble code will be retained in ECM memory. If related fault does not reoccur within a certain time frame, related trouble code will be erased from ECM memory. Intermittent failures may be caused by sensor, connector or wiring related problems. See INTERMITTENTS in the TESTS W/O CODES article.

RETRIEVING CODES

1. Enter specific test mode by connecting or disconnecting read memory and/or test mode connectors as shown in the «RELATIONSHIP BETWEEN MODES & CONNECTORS»(ref-26146-S01601813392001010500000) table. Connectors are located behind left side of instrument panel. (Scheme 1)
2. Observe malfunction indicator light (CHECK ENGINE light) or oxygen sensor monitor light. Note any trouble codes. Long illumination periods of 1.2 seconds designate tens digit in numbered codes. Short illumination periods of.2 second designate ones digit in numbered codes.
3. Tens and ones digits are separated by a.3-second interval of non-illumination. For example: 3 long flashes (1.2 seconds each) followed by 5 short flashes (.2 second each) designate code 35.
4. After a 2-second break, another code will be displayed. Once all existing codes have been displayed, sequence will repeat.

RELATIONSHIP BETWEEN MODES & CONNECTORS

Scheme 1

CLEARING CODES

After malfunction has been corrected, trouble code will clear from memory when CLEAR MEMORY mode is accessed. Unless all items check okay in D-CHECK mode, memory will not be cleared. Refer to the RELATIONSHIP BETWEEN MODES & CONNECTORS table.

SUMMARY

If no hard fault codes (or only pass codes) are present, driveability symptoms exist or intermittent codes exist, proceed to the TESTS W/O CODES article for diagnosis by symptom (ie, ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

CODE 11 - CRANKSHAFT POSITION SENSOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Check ECM input signal by connecting oscilloscope at ECM connector E30, terminals No. 6 and 7. For voltage specifications, see appropriate pin voltage chart in the «PIN VOLTAGE CHARTS»(ref-26182) article. If voltage is present, repair ECM harness connector or replace ECM as necessary. If voltage is not present, go to next step.
2. Ensure ignition is off. Disconnect ECM and crankshaft position sensor connectors. Measure resistance between ECM connector E30, terminal No. 6 and crankshaft position sensor terminal No. 1 (Black wire). In addition, measure resistance between ECM connector E30, terminal No. 7 and crankshaft position sensor terminal No. 2 (White wire). In both cases, resistance should be maximum of 10 ohms. Measure resistance between ECM connector E30, terminals No. 6, 7 and 11, and ground. Resistance should be a minimum of one megohm at each terminal.
3. If resistances are not to specification, replace or repair harness or connector. If resistances are to specification, remove crankshaft position sensor. Put positive lead of oscilloscope at crankshaft position sensor terminal No. 1 (Black wire) and negative lead at terminal No. 2 (White wire). Check for a wave profile while passing a magnet near crankshaft position sensor pick-up coil.
4. If a wave profile appears, check for problem between crankshaft position sensor and crankshaft sprocket. If a wave profile does not appear, replace crankshaft position sensor.

CODE 12 - STARTER SWITCH

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. If starter motor does not operate, repair as necessary. If starter motor operates, check ECM input signal by measuring voltage between ECM connector E29, terminal No. 12 and ground. If voltage is 13-14 volts, repair ECM connector or replace ECM. If voltage is not 13-14 volts, go to next step.
2. Turn ignition off. Disconnect ECM and starter motor connectors. Using an ohmmeter, measure resistance between ECM connector E29, terminal No. 12 and starter motor terminal No. 1 (Red/Yellow wire). Zero ohms should be present. Measure resistance between starter motor connector terminal No. 1 (Red/Yellow wire) and ground. Minimum of one megohm should be present.
3. If resistances are within specification, check the neutral position switch(M/T) or the inhibitor switch (A/T). Refer to the «SYSTEM/COMPONENT TESTS»(ref-26183) article. If resistances are not to specification, repair or replace harness, connector, or terminals.

CODE 13 - CAMSHAFT POSITION SENSOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Place oscilloscope leads between ECM connector E30, terminals No. 8 and 9. Check signal voltage on oscilloscope while cranking engine. For voltage specs., see the «PIN VOLTAGE CHARTS»(ref-26182) article. If input signal is okay, repair ECM harness connector or replace ECM as necessary. If ECM input signal is not okay, go to next step.
2. Turn ignition off. Disconnect ECM and camshaft position sensor connectors. Measure resistance between ECM connector E30, terminal No. 8 and camshaft position sensor connector terminal No. 1 (Black wire), and ECM connector E30, terminal No. 9 and camshaft position sensor connector terminal No. 2 (White wire). In both cases, resistance should be 10 ohms maximum. Measure resistance between ground and ECM connector E30, terminals No. 8, 9 and 11. Resistance should be a minimum of one megohm at each terminal.
3. If resistances are not to specification, repair or replace harness or connectors as necessary. If resistances are to specification, remove camshaft position sensor. Put positive lead of oscilloscope at camshaft position sensor terminal No. 1 (Black wire) and negative lead at terminal No. 2 (White wire). Check for a wave pattern while passing a magnet near camshaft position sensor pick-up coil.
4. If a wave pattern appears, check for problem between camshaft position sensor and camshaft sprocket. If a wave pattern does not appear, replace camshaft position sensor.

CODES 14, 15, 16 & 17 - FUEL INJECTOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Crank engine and ensure each fuel injector makes an operating sound (clicking). If fuel injectors click, check fuel pressure. See the «BASIC TESTING»(ref-26157) article. If fuel injectors do not click, go to next step.
2. Turn ignition off. Disconnect connector from each injector. Turn ignition on. Measure voltage between each injector connector power supply terminal and ground. If voltage is not at least 10 volts, repair or replace harness/connector. If voltage is at least 10 volts, check resistance between fuel injector terminals. If resistance is not 11-12 ohms, replace fuel injectors. If resistance is 11-12 ohms, go to next step.
3. Disconnect ECM connector. Measure resistance between specified ECM connector E30, terminals and fuel injector terminal. See «ECM CONNECTOR/FUEL INJECTOR TERMINAL IDENTIFICATION»(ref-26146-S11975902742001010500000) table. If less than 10 ohms are present on all terminals, repair ECM connector or replace ECM as necessary. If more than 10 ohms are present on any terminal, repair or replace harness or connector.

ECM CONNECTOR/FUEL INJECTOR TERMINAL IDENTIFICATION

CODE 21 - COOLANT TEMPERATURE SENSOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition off. Disconnect coolant temperature sensor connector. Measure resistance between coolant temperature sensor terminals. See «COOLANT TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS»(ref-26146-S29198773442001010500000) table. If resistances are not to specification, replace coolant temperature sensor. If resistances are to specification, go to next step and check harness between ECM and coolant temperature sensor. COOLANT TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS Temperature °F (°C) Ohms 68°F (20°C) 2000-3000 176°F (80°C) 270-370
2. Disconnect ECM connector E30. Measure resistance between ECM connector E30, terminal No. 3 and coolant temperature sensor connector terminal No. 1 (Black/Yellow wire). Measure resistance between ECM connector E30, terminal No. 11 and coolant temperature sensor connector terminal No. 2 (Black/White wire). A maximum of 10 ohms should be present in both cases. If not within specification, repair harness as necessary.
3. Ensure coolant temperature sensor circuit is not shorted to ground by measuring resistance between each coolant temperature sensor connector terminals and ground. Minimum of one megohm should be present.
4. If resistance measurements are not to specification, repair or replace harness or connector as necessary. If resistance measurements are okay, repair ECM harness or connector. If harness and connector are okay, replace ECM.

CODE 23 - MASS AIRFLOW SENSOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Ensure ECM is connected. Turn ignition on. Measure voltage between ECM connector E30, terminal No. 5 (backprobe) and ground. Voltage should be 0-.3 volt. Measure voltage between ECM connector E31, terminal No. 1 and ground. No voltage should be present.
2. Start and idle engine. About .8-1.2 volts should now be present between ECM connector E30, terminal No. 5 and ground. Zero voltage should be present between ECM connector E31, terminal No. 1 and ground. If voltages are to specification, repair ECM harness connector or replace ECM. If voltages are not to specification, go to next step.
3. Turn ignition off. Disconnect MAF sensor connector. Turn ignition on. Measure voltage between MAF sensor connector terminal No. 1 (Yellow/Green wire) and ground. If voltage is 10-13 volts, go to next step. If voltage is not 10-13 volts, repair or replace MAF harness or connector.
4. Turn ignition off. Disconnect ECM connector. Measure resistance between ECM connector E30, terminal No. 5 and MAF connector terminal No. 2 (Black/Blue wire), between ECM connector E30, terminal No. 22 and MAF connector terminal No. 3 (Black/Red wire), and between MAF connector terminal No. 3 (Black/Red wire) and ground. A maximum of 10 ohms should be present in all cases. If more than 10 ohms is present in any case, repair harness as necessary.
5. Measure resistance between ECM connector E30, terminal No. 5 and ground, and between ECM connector E31, terminal No. 1 and ground. A minimum of one megohm should be present in both cases. If resistances are to specification, replace MAF sensor. If resistances are not to specification, repair or replace harness.

CODE 24 - IDLE AIR CONTROL SOLENOID VALVE

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. With engine warm and idling, measure voltage between ECM connector E29, terminal No. 2 (backprobe) and ground, then measure voltage between ECM connector E29, terminal No. 1 and ground. Voltage should be less than one volt on one terminal and more than 13 volts on other terminal. Voltage readings may switch if ECM tries to regulate idle speed while testing. If voltage readings are correct, repair ECM harness connector or replace ECM. If indicated voltage readings are not present, go to next step.
2. Turn ignition off. Disconnect IAC connector. Measure resistance between IAC valve terminals No. 1 and 2, and between terminals No. 2 and 3. If 32 ohms are present, go to next step. If 32 ohms are not present, replace IAC solenoid valve.
3. Turn ignition on. Measure voltage between IAC connector terminal No. 2 (Yellow/Red wire) and ground. If minimum 10 volts are present, repair or replace connector between ECM and IAC valve. If minimum of 10 volts are not present, repair or replace harness connector.

CODE 31 - THROTTLE POSITION SENSOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition on. Ensure throttle valve is fully closed. Measure voltage between ECM connector E30, terminal No. 15 (backprobe) and ground. Voltage should be 4.4-5.5 volts. Measure voltage between ECM connector E30, terminal No. 4 and ground. Voltage should be .4-.5 volt. Measure voltage between ECM connector E30, terminal No. 11 and ground. No voltage should be present.
2. Fully open throttle valve and repeat previous voltage measurements. Voltage between ECM connector E30, terminal No. 15 and ground should be 4.4-5.5 volts. Voltage between ECM connector E30, terminal No. 4 and ground should be 3.5-4.3 volts. No voltage should be present between ECM connector E30, terminal No. 11 and ground. If voltages are correct, repair ECM harness connector or replace ECM. If voltages are not correct, go to next step.
3. Turn ignition off. Disconnect ECM and TPS connectors. Measure resistance between ECM connector E30, and TPS connector terminals. See «ECM & TPS TERMINAL IDENTIFICATION»(ref-26146-S07076276682001010500000) table. Less than 10 ohms should be present for all measurements. Measure resistance between ground and ECM connector E30, terminals No. 15, 4 and 11. Resistance for all measurements should be at least one megohm. ECM & TPS TERMINAL IDENTIFICATION ECM Terminal TPS Terminal (Wire Color) No. 15 No. 1 (Black/White) No. 4 No. 2 (White) No. 11 No. 3 (Red)
4. If resistances are not to specification, repair or replace harness connector. If resistances are to specification, check and adjust TPS. See THROTTLE POSITION SENSOR in the «ADJUSTMENTS»(ref-26139) article. If TPS cannot adjust correctly, replace TPS.

CODE 32 - OXYGEN SENSOR (O2S)

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition off. Disconnect ECM and oxygen sensor connectors. Measure resistance between ECM connector E30, terminal No. 10 and oxygen sensor connector terminal No. 4 (White wire). Zero ohms should be present. Measure resistance between oxygen sensor connector terminal No. 4 (White wire) and ground. Minimum of one megohm should be present. If resistances are not to specification, repair or replace harness connector. If resistances are okay, go to next step.
2. Reconnect oxygen sensor connector. Start and run engine at idle. Disconnect oxygen sensor connector. Measure voltage between oxygen sensor connector terminal No. 4 (White wire) and ground. If voltage is fluctuating between .1 and 1.0 volt, repair ECM harness connector or replace ECM. If voltage is not fluctuating between .1 and 1.0 volt, replace oxygen sensor.

CODE 33 - VEHICLE SPEED SENSOR NO. 2

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Remove instrument cluster assembly. Measure resistance between connector terminals No. 8 and 11 of combination meter while rotating speedometer cable rotor with screwdriver. (Scheme 8)and (Scheme 3). If resistance switches from more than one megohm to less than 10 ohms (4 times per revolution), go to next step. If resistance does not switch as indicated, replace combination meter.
2. Turn ignition off. Disconnect ECM connector. Measure resistance between ECM connector E29, terminal No. 4 and instrument cluster connector terminal No. 8. (Scheme 9) Less than 10 ohms should be present. Measure resistance between instrument cluster connector terminal No. 4 and ground. At least one megohm should be present. If resistances are as specified, repair or replace harness connector. If resistances are not to specification, go to next step.
3. Measure resistance between instrument cluster connector terminal No. 8 and ground. If resistance is not at least one megohm, repair or replace harness connector. If resistance is not to specification, repair ECM harness connector or replace ECM.

Scheme 8

Scheme 9

CODE 34 - EGR SOLENOID VALVE

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition on. Measure voltage between ECM connector E30, terminal No. 18 (backprobe) and ground. If about 10 volts are present, repair ECM harness connector or replace ECM. If about 10 volts are not present, go to next step.
2. Turn ignition off. Disconnect EGR solenoid valve connector. Measure resistance between EGR solenoid valve connector terminals. If resistance is 36 ohms at 68°F (20°C), go to next step. If resistance is not 36 ohms at 68°F (20°C), replace EGR solenoid valve.
3. Turn ignition on. Measure voltage between EGR solenoid valve connector terminal No. 2 (White/Black wire) and ground. If voltage is about 10 volts, repair or replace harness connector between ECM and EGR solenoid valve. If voltage is not to specification, repair power supply circuit.

CODE 35 - PURGE CONTROL SOLENOID VALVE

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition on. Measure voltage between ECM connector E30, terminal No. 19 (backprobe) and ground. If voltage is 10-13 volts, repair ECM harness connector or replace ECM. If voltage is not 10-13 volts, go to next step.
2. Turn ignition off. Disconnect purge control solenoid valve. Measure resistance between solenoid valve terminals. Resistance should be 36 ohms at 68°F (20°C). If resistance is not to specification, replace purge control solenoid valve. If resistance is to specification, go to next step.
3. Turn ignition on. Measure voltage between purge control solenoid valve connector terminal No. 1 (Yellow/Red wire) and ground. If about 10 volts are present, repair or replace harness connector between ECM and purge control solenoid valve. If about 10 volts are not present, repair or replace power supply circuit.

CODE 36 - AIR SUCTION SOLENOID VALVE

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition on. Measure voltage between ECM connector E31, terminal No. 3 (backprobe) and ground. If about 10 volts are present, repair ECM harness connector or replace ECM. If about 10 volts are not present, go to next step.
2. Turn ignition off. Disconnect air suction solenoid valve connector. Measure resistance between air suction solenoid valve connector terminals. Resistance should be 36 ohms at 68°F (20°C). If resistance is not to specification, replace air suction solenoid valve. If resistance is to specification, go to next step.
3. Turn ignition on. Measure voltage between air suction solenoid valve connector terminal No. 1 (Yellow/Red wire) and ground. If about 10 volts are present, repair or replace harness connector between ECM and air suction solenoid valve. If about 10 volts are not present, repair or replace power supply circuit.

CODE 41 - AIR/FUEL LEARNING CONTROL

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

Ensure fuel injectors, mass airflow sensor, engine coolant temperature sensor, throttle position sensor, oxygen sensor, and fuel pressure are operating within specifications. See

1. «CODES 14, 15, 16 & 17 - FUEL INJECTOR»(ref-26146-S19642782352001010500000)
2. «CODE 23 - MASS AIRFLOW SENSOR»(ref-26146-S13212617032001010500000)
3. «CODE 21 - COOLANT TEMPERATURE SENSOR»(ref-26146-S08696468352001010500000)
4. «CODE 31 - THROTTLE POSITION SENSOR»(ref-26146-S07324225932001010500000)
5. «CODE 32 - OXYGEN SENSOR (O2S)»(ref-26146-S30860578632001010500000)

Repair as necessary. If systems are okay, repair ECM harness connector or replace ECM.

CODE 51 - NEUTRAL POSITION SWITCH - M/T

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition on. Measure voltage between ECM connector E29, terminal No. 16 (backprobe) and ground. With transmission selector lever in Neutral, 10-14 volts should be present. With transmission selector lever in any position but Neutral, zero voltage should be present. If voltages are to specification, repair ECM connector or replace ECM. If voltages are not to specification, go to next step.
2. Turn ignition off. Disconnect 2-pin transmission harness connector. Measure resistance between connector harness terminals. In Neutral, at least one megohm should be present. With transmission selector lever in any position but Neutral, less than 10 ohms should be present. If resistances are not to specification, replace neutral position switch. If resistances are to specification, go to next step.
3. Turn ignition on. Measure voltage between neutral position switch connector terminal No. 1 (Light Green/Yellow wire) and ground. At least 10 volts should be present. If voltage is not to specification, repair power supply circuit. If voltage is to specification, repair or replace harness between ECM and neutral position switch.

CODE 51 - INHIBITOR SWITCH - A/T

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition on. Measure voltage between ECM connector E29, terminal No. 16 (backprobe) and ground. In Park or Neutral, 10-14 volts should be present. In all other positions, zero volts should be present. If voltages are not to specification, go to next step. If voltages are to specification, repair ECM harness or connector. If harness and connector are okay, replace ECM.
2. Turn ignition off. Disconnect ECM and transmission harness 12-pin connector. Measure resistance between transmission harness 12-pin connector terminals No. 1 (Light Green/Yellow wire), No. 3 (Blue/Orange wire), and ECM connector E29, terminal No. 16. Less than 10 ohms should be present in both cases. Measure resistance between ECM connector E29, terminal No. 16 and ground. Minimum of one megohm should be present.
3. If resistances are not to specification, repair or replace harness. If resistances are to specification, check and repair inhibitor switch and wiring as necessary.

CODE 55 - RECIRCULATION GAS TEMPERATURE SENSOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition on. Measure voltage between ECM connector E31, terminal No. 4 (backprobe) and ground. At 68°F (20°C), 4-4.8 volts should be present. At 212°F (100°C), .4-1.2 volts should be present. If voltages are to specification, repair ECM harness connector or replace ECM. If voltages are not to specification, go to next step and check harness between ECM and recirculation gas temperature sensor.
2. Turn ignition off. Disconnect recirculation gas temperature sensor connector. Measure resistance between gas temperature sensor connector terminal No. 1 (Black/White wire) and ECM connector E31, terminal No. 4. Less than 10 ohms should be present. Measure resistance between ECM connector E31, terminal No. 4 and ground. At least one megohm should be present.
3. If resistances are not to specification, repair or replace harness. If resistances are to specification, replace recirculation gas temperature sensor.

CODE 56 - EGR SYSTEM

Check EGR system vacuum and gas line. See EGR SYSTEM in the SYSTEM/COMPONENT TESTS article. If vacuum and gas line are okay, replace EGR valve.

CODE 61 - FUEL TANK PRESSURE CONTROL SOLENOID VALVE

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition switch to ON. Measure voltage between ECM connector E29, terminal No. 21 and ground. If voltage is 10 volts or more, go to next step. If voltage is less than 10 volts, go to step No. 3.
2. Turn ignition switch to OFF. Disconnect connector from fuel tank pressure control solenoid valve. Turn ignition switch to ON. Measure voltage between ECM connector E29, terminal No. 21 and ground. If voltage is 10 volts or more, repair short circuit between ECM and fuel tank pressure control solenoid valve connector. After repair, replace ECM. If voltage is less than 10 volts, turn ignition switch to OFF. Measure resistance between fuel tank pressure control solenoid valve terminals No. 1 and 2. If resistance is one ohm or less, replace fuel tank pressure control solenoid valve and ECM. If resistance is more than one ohm, inspect for poor contact in ECM connector. If there is poor contact, repair ECM connector. If contact is good, replace ECM.
3. Turn ignition switch to OFF. Disconnect connectors from ECM and fuel tank pressure control solenoid valve connector (R46). Measure resistance between solenoid valve connector R46, terminal No. 2 and ground. If resistance is 10 ohms or less, repair short circuit in harness between ECM and solenoid valve connector. If resistance was more than 10 ohms, measure resistance between ECM connector E29, terminal No. 21 and solenoid valve connector R46, terminal No. 2. If resistance is one ohm or less, go to step 4). If resistance is more than one ohm, repair open circuit in harness between ECM and solenoid valve connector, poor contact at ECM connector, poor contact at fuel tank pressure control solenoid valve connector, or poor contact in any harness coupling connector between ECM and solenoid valve connector.
4. With fuel tank pressure control solenoid valve disconnected, measure resistance between terminals No. 1 and 2. If resistance is between 10-100 ohms, go to next step. If resistance is not between 10-100 ohms, replace fuel tank pressure control solenoid valve.
5. Connect ECM connector. Turn ignition switch to ON. Measure voltage between solenoid valve connector terminal No. 1 and ground. If voltage is 10 volts or more, repair poor contact in fuel tank pressure control solenoid valve connector. If voltage is less than 10 volts, repair open in harness between main relay and solenoid valve, repair poor contact in main relay connector or repair poor contact in any coupling connector between ECM and fuel tank pressure control solenoid valve connector.

CODE 62 - FUEL TEMPERATURE SENSOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition switch to OFF. Connect Subaru Select Monitor (SSM) to data link connector. Turn ignition switch and SSM switch ON. Start engine and select SSM function mode F17 (fuel temperature is indicated in °F). If value is greater than 300°F, go to step 2). If value is less than 3). If value is not less than - 40°F, repair poor contact in ECM connector, repair poor contact at fuel pump connector or repair poor contact in any coupling between ECM and fuel pump.
2. Turn ignition switch OFF. Remove fuel pump access cover. Disconnect connector from fuel pump. Turn ignition and SSM ON and select function mode F17. If indicated value is less than - 40°F, replace fuel temperature sensor. If value is not less than - 40°F, repair short circuit in harness between ECM and fuel pump connector.
3. With ignition OFF and access cover removed, disconnect fuel pump connector. Turn ignition switch ON. Measure voltage between fuel pump connector R38, terminal No. 2 and ground. If voltage is 4 volts or more, go to next step. If voltage is less than 4 volts, repair open circuit between ECM and fuel pump connector, repair poor contact in ECM connector, repair poor contact in fuel pump connector or repair poor contact in any coupling in wiring harness between ECM and fuel pump connector.
4. Turn ignition switch to OFF. Measure resistance between fuel pump connector terminal No. 3 and ground. If resistance is 5 ohms or less, replace fuel temperature sensor. If resistance is more than 5 ohms, repair open in harness between ECM and fuel pump connector, repair poor contact in ECM connector, repair poor contact in fuel pump connector or repair poor contact in any coupling in harness between ECM and fuel pump connector.

CODE 63 - FUEL TANK PRESSURE SENSOR

Note. Refer to illustration for connector and terminal identification. (Scheme 2)- (Scheme 7).

1. Turn ignition switch to OFF. Remove and then replace fuel filler cap. Connect Subaru Select Monitor (SSM) to data link connector. Turn ignition switch and SSM switch ON. Select function mode F18 on SSM to indicate pressure sensor output. If value indicated is less than 2). If value is more than 7.2 kPa, go to step No. 4. If value is between - 7.2-7.2 kPa, repair open in harness between ECM and fuel tank pressure sensor connector, poor contact in ECM connector, poor contact in fuel tank pressure sensor connector or repair contact in any coupling between ECM and fuel tank pressure sensor connector.
2. Measure voltage between ECM connector E30, terminal No. 3 and ground. If voltage is 4.5 volts or more, go to next step. If voltage changes more than 4.5 volts while shaking harness and connector of ECM, repair contact in ECM connector. If no change while shaking, replace ECM. Measure voltage between ECM connector E31, terminal No.5 and ground. If voltage is 0.2 volt or less, go to step 3). If voltage is more than 0.2 volt, select function mode F18 on SSM to read fuel tank pressure sensor output signal. If SSM reading changes more than - 7.2 kPa while shaking ECM harness and connector, repair poor contact in ECM connector. If no change, go to next step.
3. Turn ignition switch to OFF. Remove right rear quarter trim inside trunk. Disconnect fuel tank pressure sensor connector. Turn ignition switch to ON. Measure voltage between fuel tank pressure sensor connector R43, and ground. If voltage is less than 4.5 volts, repair open in harness between ECM and fuel tank pressure sensor connector, repair poor contact in ECM connector, repair poor contact in fuel tank pressure sensor connector or repair poor contact in any coupling between ECM and pressure sensor connector. If voltage is more than 4.5 volts, turn ignition switch to OFF and disconnect connector from ECM. Measure resistance between ECM connector E31, terminal No. 5 and pressure sensor connector R43, terminal No.1, and ECM connector E30, terminal No. 11 and pressure sensor connector R43, terminal No. 2. In each case, if resistance is one ohm or less, go to next step. If resistance is more than one ohm, repair open in harness between ECM and pressure sensor connector, repair poor contact in ECM connector, repair poor contact in fuel tank pressure sensor connector, or repair poor contact in any harness coupling between ECM and pressure sensor connector. Measure resistance between fuel tank pressure sensor connector R43, terminal No. 1 and ground. If resistance is not 500,000 ohms or more, repair short in harness between ECM and fuel tank pressure sensor connector. If there is 500,000 ohms or more resistance, repair poor contact in pressure sensor connector or replace fuel tank pressure sensor if necessary.
4. Turn ignition switch to OFF. Remove right rear quarter trim inside trunk. Disconnect fuel tank pressure sensor connector. Turn ignition switch to ON. Select function mode F18 on SSM to read pressure sensor output signal. If value is 7.2 kPa or more, repair short circuit in harness between ECM and fuel tank pressure sensor connector. If value is less than 7.2 kPa, replace fuel tank pressure sensor.

Scheme 10

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Scheme 16

Scheme 17

Scheme 18

Scheme 19

Scheme 20

Scheme 21

Scheme 22

Scheme 23

Scheme 24

Scheme 25

Scheme 26

Scheme 27

Scheme 28

Scheme 29

Note. Before starting any testing, connect Subaru Select Monitor (SSM) or OBD-II general scan tool (Scheme 10), and read data. For operational details of OBD-II scan tester, refer to manufacturers instruction manual.

Condition

Following conditions continue with engine speed at idle

1. Uneven idle
2. Engine stalls
3. Poor driveability

"a" - Only One Cylinder

Check following items for that cylinder

1. Spark plug
2. Spark plug wire
3. Fuel injector
4. Compression

"b" - Group Of Cylinders No. 1 And 2

Check following items for cylinders No. 1 and 2

1. Spark plugs
2. Fuel injectors
3. Igniters, coils, etc.

"c" - Group Of Cylinders No. 3 And 4

Check following items for cylinders No. 3 and 4

1. Spark plugs
2. Fuel injectors
3. Igniters, coils, etc.

"d" - Group Of Cylinders No. 1 And 3

Check following items for cylinders No. 1 and 3

1. Spark plugs
2. Fuel injectors
3. Skipped timing belt teeth

"e" - Group Of Cylinders No. 2 And 4

Check following items for cylinders No. 2 and 4

1. Spark plugs
2. Fuel injectors
3. Skipped timing belt teeth

"f" - Cylinder At Random

If engine idle is not rough, go to DTC P0170 and retest. If engine idle is rough, refer to already noted minimum EGR pressure (function mode F38). If EGR pressure is less than 0.39 in. Hg, clean EGR valve. If EGR pressure value is more than 0.39 in. Hg, go to DTC P0170 and retest.

Note. Remove and blow away exhaust deposits. Ensure valve operates smoothly and valve seat area is completely clean. Replace EGR valve if required.

"a"

Conduct CLEAR MEMORY and INSPECTION MODES.

"b"

Connect SSM to data link connector.

Start and warm engine until radiator fan completes one cycle (all accessories OFF).

Turn SSM to ON and select function mode FA4.

Drive vehicle at 52-58 MPH (83-93 km/h) until LED No. 5 is turned ON.

Note. Keep throttle valve opening steady. Diagnosis will be interrupted if opening varies. Diagnosis starts in 190 seconds after starting engine and requires 4 seconds to run. Transmission should be in "D" range for diagnosis.

"f"

On SSM, select function mode FB0. Confirm "No Trouble" indication on SSM.

If no hard fault codes are present, driveability symptoms exist or intermittent codes exist, proceed to INTRODUCTION .

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed with self-diagnostics. If no fault codes are present after entering self-diagnostics, proceed to TESTS W/O CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.