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Engine Control System (Diagnostic Codes (P0128-P0420)): Diagnosis Scion tC II рестайлинг

Testing & Diagnostics 9 illustrations ~6191 words

INSPECTION PROCEDURE

HINT

  1. This DTC relates to the thermostat.
  2. Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

Malfunctioning areas can be identified by performing the Control the Injection Volume function provided in the Active Test. The Control the Injection Volume function can help to determine whether the air fuel ratio sensor, heated oxygen sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the Control the Injection Volume operation using the Techstream.

  1. Connect the Techstream to the DLC3.
  2. Start the engine and turn the Techstream on.
  3. Warm up the engine and run the engine at an engine speed of 2500 rpm for approximately 90 seconds.
  4. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor.
  5. Perform the Active Test operation with the engine idling.
  6. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2) displayed on the Techstream.

HINT

  1. Change the fuel injection volume within the range of -12.5% to +12.5%.
  2. The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.
  3. If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.
Techstream Display (Sensor)Injection VolumeStatusVoltage
AFS Voltage B1S1 (A/F)+12.5%RichBelow 3.1 V
AFS Voltage B1S1 (A/F)12.5%LeanHigher than 3.4 V
O2S B1S2 (HO2)+12.5%RichHigher than 0.55 V
O2S B1S2 (HO2)12.5%LeanBelow 0.4 V

Note. The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.

Case Air Fuel Ratio Sensor (Sensor 1) Output Voltage Heated Oxygen Sensor (Sensor 2) Output Voltage Main Suspected Trouble Area 1 - 2 Air fuel ratio sensor Air fuel ratio sensor heater Air fuel ratio sensor circuit 3 Heated oxygen sensor Heated oxygen sensor heater Heated oxygen sensor circuit 4 Fuel injector assembly Fuel pressure Gas leak from exhaust system (air-fuel ratio extremely rich or lean)

Scheme 137

Scheme 137
Scheme 137

Scheme 138

Scheme 138
Scheme 138

Scheme 139

Scheme 139
Scheme 139

Scheme 140

Scheme 140
Scheme 140

HINT

  1. Following the Control the Injection Volume procedure enables technicians to check and graph the voltage outputs of both the air fuel ratio and heated oxygen sensors.
  2. To display the graph, enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / All Data / AFS Voltage B1S1 and O2S B1S2.
  3. Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  4. If the OX1B wire from the ECM connector is short-circuited to the +B wire, DTC P0136 will be stored.
  5. Sensor 1 refers to the sensor closest to the engine assembly.
  6. Sensor 2 refers to the sensor farthest away from the engine assembly.

HINT

Malfunctioning areas can be identified by performing the Control the Injection Volume function provided in the Active Test. The Control the Injection Volume function can help to determine whether the air fuel ratio sensor, heated oxygen sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the Control the Injection Volume operation using the Techstream.

  1. Connect the Techstream to the DLC3.
  2. Start the engine and turn the Techstream on.
  3. Warm up the engine and run the engine at an engine speed of 2500 rpm for approximately 90 seconds.
  4. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor.
  5. Perform the Active Test operation with the engine idling.
  6. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2) displayed on the Techstream.

HINT

  1. Change the fuel injection volume within the range of -12.5% to +12.5%.
  2. The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.
  3. If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.
Techstream Display (Sensor)Injection VolumeStatusVoltage
AFS Voltage B1S1 (A/F)+12.5%RichBelow 3.1 V
AFS Voltage B1S1 (A/F)12.5%LeanHigher than 3.4 V
O2S B1S2 (HO2)+12.5%RichHigher than 0.55 V
O2S B1S2 (HO2)12.5%LeanBelow 0.4 V

Note. The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.

Case Air Fuel Ratio Sensor (Sensor 1) Output Voltage Heated Oxygen Sensor (Sensor 2) Output Voltage Main Suspected Trouble Area 1 - 2 Air fuel ratio sensor Air fuel ratio sensor heater Air fuel ratio sensor circuit 3 Heated oxygen sensor Heated oxygen sensor heater Heated oxygen sensor circuit 4 Fuel injector assembly Fuel pressure Gas leak from exhaust system (air-fuel ratio extremely rich or lean)

HINT

  1. Following the Control the Injection Volume procedure enables technicians to check and graph the voltage outputs of both the air fuel ratio and heated oxygen sensors.
  2. To display the graph, enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / All Data / AFS Voltage B1S1 and O2S B1S2.
  3. Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  4. If the OX1B wire from the ECM connector is short-circuited to the +B wire, DTC P0136 will be stored.
  5. Sensor 1 refers to the sensor closest to the engine assembly.
  6. Sensor 2 refers to the sensor farthest away from the engine assembly.

HINT

  1. A low air fuel ratio sensor voltage could be caused by a rich air fuel mixture. Check for conditions that would cause the engine to run rich.
  2. A high air fuel ratio sensor voltage could be caused by a lean air fuel mixture. Check for conditions that would cause the engine to run lean.
  3. Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was moving or stationary, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
  4. Sensor 1 refers to the sensor mounted in front of the Three-way Catalytic Converter (TWC) and located near the engine assembly.
  5. Sensor 1 refers to the sensor closest to the engine assembly.
  6. Sensor 2 refers to the sensor farthest away from the engine assembly.

HINT

  1. A low air fuel ratio sensor voltage could be caused by a rich air fuel mixture. Check for conditions that would cause the engine to run rich.
  2. A high air fuel ratio sensor voltage could be caused by a lean air fuel mixture. Check for conditions that would cause the engine to run lean.
  3. Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was moving or stationary, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
  4. Sensor 1 refers to the sensor mounted in front of the Three-way Catalytic Converter (TWC) and located near the engine assembly.
  5. Sensor 1 refers to the sensor closest to the engine assembly.
  6. Sensor 2 refers to the sensor farthest away from the engine assembly.

HINT

  1. Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  2. A low air fuel ratio sensor voltage could be caused by a rich air-fuel mixture. Check for conditions that would cause the engine to run rich.
  3. A high air fuel ratio sensor voltage could be caused by a lean air-fuel mixture. Check for conditions that would cause the engine to run lean.
  4. Sensor 1 refers to the sensor closest to the engine assembly.
  5. Sensor 2 refers to the sensor farthest away from the engine assembly.

Scheme 141

Scheme 141: PROCEDURE
Scheme 141: PROCEDURE
  1. CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0171 OR P0172) Connect the Techstream to the DLC3. Turn the ignition switch to ON. Turn the Techstream on. Enter the following menus: Powertrain / Engine / Trouble Codes. Read the DTCs. RESULT Result Proceed to P0171 or P0172 is output A P0171 or P0172 and other DTCs are output B HINT: If any DTCs other than P0171 or P0172 are output, troubleshoot those DTCs first. B --> See step 23 A: Go to next step
  2. CHECK PCV HOSE CONNECTIONS Check the PCV hose connections. Refer to «ON-VEHICLE INSPECTION [05/2013 - ] - Step 2»(ref-615246-S35610607062014050900000) . OK PCV hose is connected correctly and is not damaged. NG --> See step 24 OK: Go to next step
  3. CHECK AIR INDUCTION SYSTEM Check the air induction system for vacuum leaks. Refer to «ON-VEHICLE INSPECTION [05/2013 - ] - Step 1»(ref-615245-S05242304412014050900000) . OK No leaks in air induction system. HINT: Perform "Inspection After Repair" after repairing or replacing the air induction system. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . NG --> See step 25 OK: Go to next step
  4. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME FOR A/F SENSOR) Connect the Techstream to the DLC3. Start the engine. Turn the Techstream on. Warm up the engine and run the engine at an engine speed of 2500 rpm for approximately 90 seconds. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor. Perform the Control the Injection Volume operation with the engine idling. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2) displayed on the Techstream. HINT: Change the fuel injection volume within the range of -12.5% to +12.5%. The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds. If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning. Techstream Display (Sensor) Injection Volume Status Voltage AFS Voltage B1S1 (Air fuel ratio) +12.5% Rich Below 3.1 V AFS Voltage B1S1 (Air fuel ratio) -12.5% Lean Higher than 3.4 V O2S B1S2 (Heated oxygen) +12.5% Rich Higher than 0.55 V O2S B1S2 (Heated oxygen) -12.5% Lean Below 0.4 V RESULT Status of AFS Voltage B1S1 Status of O2S B1S2 Air Fuel Ratio Condition and Air Fuel Ratio Sensor Condition Suspected Trouble Area Proceed to Lean/Rich Lean/Rich Normal - A Lean Lean Actual air fuel ratio lean PCV valve and hose PCV hose connections Fuel injector assembly blockage Gas leaks from exhaust system Intake system Fuel pressure Mass air flow meter assembly Engine coolant temperature sensor A Rich Rich Actual air fuel ratio rich Fuel injector assembly leakage or blockage Gas leaks from exhaust system Ignition system Fuel pressure Mass air flow meter assembly Engine coolant temperature sensor A Lean Lean/Rich Air fuel ratio sensor malfunction Air fuel ratio sensor B Rich Lean/Rich Air fuel ratio sensor malfunction Air fuel ratio sensor B Lean: During the Control the Injection Volume Active Test, the air fuel ratio sensor output voltage (AFS Voltage) is consistently higher than 3.4 V, and the heated oxygen sensor output voltage (O2S) is consistently below 0.4 V. Rich: During the Control the Injection Volume Active Test, the AFS Voltage is consistently below 3.1 V, and the O2S is consistently higher than 0.55 V. Lean/Rich: During the Control the Injection Volume Active Test, the output voltage of the heated oxygen sensor alternates correctly. HINT: Refer to "Data List / Active Test" [AFS Voltage B1S1 and O2S B1S2]. Refer to «DATA LIST / ACTIVE TEST [05/2013 - 01/2014]»(ref-615234-S35938653532014050900000) . B --> See step 11 A: Go to next step
  5. READ VALUE USING TECHSTREAM (COOLANT TEMP) Connect the Techstream to the DLC3. Turn the ignition switch to ON. Turn the Techstream on. Enter the following menus: Powertrain / Engine / Data List / All Data / Coolant Temp. Read Coolant Temp twice, when the engine is both cold and warmed up. Standard With cold engine: Same as ambient air temperature. With warm engine: Between 75°C and 100°C (167°F and 212°F). HINT: Perform "Inspection After Repair" after replacing the engine coolant temperature sensor. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . NG --> See step 26 OK: Go to next step
  6. READ VALUE USING TECHSTREAM (MAF) Connect the Techstream to the DLC3. Turn the ignition switch to ON. Turn the Techstream on. Enter the following menus: Powertrain / Engine / Data List / All Data / MAF and Coolant Temp. Allow the engine to idle until Coolant Temp reaches 75°C (167°F) or higher. Read MAF with the engine speed at 3000 rpm. Standard Between 8 gm/sec and 22 gm/sec (shift lever: N; A/C: Off). NG --> See step 16 OK: Go to next step
  7. CHECK FUEL PRESSURE Check the fuel pressure. Refer to «ON-VEHICLE INSPECTION [05/2013 - 01/2014] - Step 2»(ref-615250-S34834712852014050900000) . NG --> REPAIR OR REPLACE FUEL SYSTEM OK: Go to next step
  8. CHECK FOR EXHAUST GAS LEAK Check for exhaust gas leaks. OK No gas leaks. HINT: Perform "Inspection After Repair" after repairing or replacing the exhaust system. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . NG --> REPAIR OR REPLACE EXHAUST SYSTEM OK: Go to next step
  9. CHECK FOR SPARKS AND IGNITION Perform a spark test. Refer to «ON-VEHICLE INSPECTION [05/2013 - ] - Step 1»(ref-615243-S15300027832014050900000) . HINT: If the result of the spark test is normal, proceed to the next step. If the spark plugs or ignition system malfunctions, engine misfire may occur. The misfire count can be read using the Techstream. Enter the following menus: Powertrain / Engine / Data List / Gas Misfire / Cylinder #1 Misfire Count (to Cylinder #4 Misfire Count). Perform "Inspection After Repair" after repairing or replacing the ignition system. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . NEXT: Go to next step
  10. INSPECT FUEL INJECTOR ASSEMBLY (INJECTION AND VOLUME) Check the injection and volume. Refer to «INSPECTION [05/2013 - ]»(ref-615244-S28235590902014050900000) . HINT: Perform "Inspection After Repair" after replacing the fuel injector assembly. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . OK --> See step 15 NG --> See step 27
  11. INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE) Inspect the air fuel ratio sensor. Refer to «INSPECTION [05/2013 - ]»(ref-615228-S25292060302014050900000) . HINT: Perform "Inspection After Repair" after repairing or replacing the air fuel ratio sensor. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . NG --> See step 28 OK: Go to next step
  12. CHECK TERMINAL VOLTAGE (+B OF AIR FUEL RATIO SENSOR) Disconnect the air fuel ratio sensor connector. Turn the ignition switch to ON. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Switch Condition Specified Condition B17-2 (+B) - Body ground Ignition switch ON 11 to 14 V TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Air Fuel Ratio Sensor) NG --> See step 21 OK: Go to next step
  13. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM) Disconnect the air fuel ratio sensor connector. Disconnect the ECM connector. Measure the resistance according to the value(s) in the table below. STANDARD RESISTANCE Tester Connection Condition Specified Condition B17-1 (HA1A) - B30-18 (HA1A) Always Below 1 ohms B17-3 (A1A+) - B30-103 (A1A+) Always Below 1 ohms B17-4 (A1A-) - B30-126 (A1A-) Always Below 1 ohms B17-1 (HA1A) or B30-18 (HA1A) - Body ground Always 10 kohms or higher B17-3 (A1A+) or B30-103 (A1A+) - Body ground Always 10 kohms or higher B17-4 (A1A-) or B30-126 (A1A-) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  14. REPLACE AIR FUEL RATIO SENSOR Replace the air fuel ratio sensor. Refer to «REMOVAL [05/2013 - ]»(ref-615228-S10639288742014050900000) . HINT: Perform "Inspection After Repair" after replacing the air fuel ratio sensor. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . NEXT: Go to next step
  15. PERFORM CONFIRMATION DRIVING PATTERN Connect the Techstream to the DLC3. Turn the ignition switch to ON. Turn the Techstream on. Clear the DTCs. Refer to «DTC CHECK / CLEAR [05/2013 - 01/2014]»(ref-615120-S02653872462014050900000) . Turn the ignition switch off. Turn the ignition switch to ON and turn the Techstream on. Start the engine and warm it up. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern. Enter the following menus: Powertrain / Engine / Trouble Codes. Read the DTCs. RESULT Result Proceed to DTC P0171 or P0172 is output A DTC is not output B B --> END A: Go to next step
  16. CHECK HARNESS AND CONNECTOR Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter and ECM. Refer to «ELECTRONIC CIRCUIT INSPECTION PROCEDURE [05/2013 - ]»(ref-615109-S05659225472014050900000) . HINT: Repair any problems. NEXT: Go to next step
  17. CHECK WHETHER DTC OUTPUT RECURS Connect the Techstream to the DLC3. Turn the ignition switch to ON. Turn the Techstream on. Clear the DTCs. Refer to «DTC CHECK / CLEAR [05/2013 - 01/2014]»(ref-615120-S02653872462014050900000) . Turn the ignition switch off. Turn the ignition switch to ON and turn the Techstream on. Start the engine and warm it up. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern. Enter the following menus: Powertrain / Engine / Trouble Codes. Read the DTCs. RESULT Result Proceed to DTC P0171 or P0172 is output A DTC is not output B B --> END A: Go to next step
  18. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) Disconnect the mass air flow meter connector. Disconnect the ECM connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition B2-5 (VG) - B30-94 (VG) Always Below 1 ohms B2-4 (E2G) - B30-117 (E2G) Always Below 1 ohms B2-5 (VG) or B30-94 (VG) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  19. REPLACE MASS AIR FLOW METER SUB-ASSEMBLY Replace the mass air flow meter sub-assembly. Refer to «REMOVAL [05/2013 - ]»(ref-615228-S10339709762014050900000) . HINT: If the result of the inspection performed in step 6 indicated no problem, proceed to the next step without replacing the mass air flow meter sub-assembly. Perform "Inspection After Repair" after replacing the mass air flow meter. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . NEXT: Go to next step
  20. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Connect the Techstream to the DLC3. Turn the ignition switch to ON. Turn the Techstream on. Clear the DTCs. Refer to «DTC CHECK / CLEAR [05/2013 - 01/2014]»(ref-615120-S02653872462014050900000) . Turn the ignition switch off. Turn the ignition switch to ON and turn the Techstream on. Start the engine and warm it up. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern. Enter the following menus: Powertrain / Engine / Trouble Codes. Read the DTCs. RESULT Result Proceed to DTC is not output A DTC P0171 or P0172 is output B B --> See step 29 A --> END
  21. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR AND BODY GROUND - INTEGRATION RELAY) Disconnect the air fuel ratio sensor connector. Remove the integration relay from the engine room relay block. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition B17-2 (+B) - 1B-8 Always Below 1 ohms 1B-7 - Body ground Always Below 1 ohms B17-2 (+B) or 1B-8 - Body ground Always Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  22. INSPECT INTEGRATION RELAY (EFI NO. 2) Inspect the integration relay (EFI NO. 2). Refer to «ON-VEHICLE INSPECTION [05/2013 - ] - Step 3»(ref-615228-S19103065862014050900000) . NG --> REPLACE INTEGRATION RELAY OK --> See step 30
  23. GO TO DTC CHART. Refer to «DIAGNOSTIC TROUBLE CODE CHART [05/2013 - 01/2014]»(ref-615234-S41552064272014050900000)
  24. REPAIR OR REPLACE PCV HOSE. Refer to «REMOVAL [05/2013 - 01/2014]»(ref-615251-S07057139652014050900000)
  25. REPAIR OR REPLACE AIR INDUCTION SYSTEM. Refer to «REMOVAL [05/2013 - 01/2014]»(ref-615249-S35888103472014050900000)
  26. REPLACE ENGINE COOLANT TEMPERATURE SENSOR. Refer to «REMOVAL [05/2013 - ]»(ref-615228-S06137183572014050900000)
  27. REPLACE FUEL INJECTOR ASSEMBLY. Refer to «REMOVAL [05/2013 - 01/2014]»(ref-615244-S17953342372014050900000)
  28. REPLACE AIR FUEL RATIO SENSOR. Refer to «REMOVAL [05/2013 - ]»(ref-615228-S10639288742014050900000)
  29. REPLACE ECM. Refer to «REMOVAL [05/2013 - 01/2014]»(ref-615228-S17169059992014050900000)
  30. CHECK ECM POWER SOURCE CIRCUIT. Refer to «ECM Power Source Circuit»(ref-615235-S16917092912014050900000)

HINT

  1. Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  2. A low air fuel ratio sensor voltage could be caused by a rich air-fuel mixture. Check for conditions that would cause the engine to run rich.
  3. A high air fuel ratio sensor voltage could be caused by a lean air-fuel mixture. Check for conditions that would cause the engine to run lean.
  4. Sensor 1 refers to the sensor closest to the engine assembly.
  5. Sensor 2 refers to the sensor farthest away from the engine assembly.

HINT

  1. Check the "Fuel Cut Elps Time" in the Data List or the Freeze Frame Data. If the elapsed time is over 0 seconds, then the engine speed is high (engine speed at which fuel cut occurs + 500 rpm). When this has happened, there is the possibility that the No. 1 valve rocker arm sub-assembly will become loose and a fire could start, so check that the No. 1 valve rocker arm sub-assembly is properly attached. Refer to «COMPONENTS [05/2013 - ]»(ref-615223-S34997177162014050900000) .
  2. By clearing the DTC, "Fuel Cut Elps Time" will be cleared.
  3. If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.
  4. Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  5. If misfire does not recur when the vehicle is brought to the workshop, reproduce the conditions stored in the ECM as freeze frame data.
  6. If the misfiring still cannot be reproduced even though the conditions stored in the ECM as freeze frame data have been reproduced, one of the following factors may be a cause of the problem: The fuel level is low. Improper fuel is being used. The spark plugs are dirty.
  7. After finishing repairs, check that no misfires occur in each cylinder (cylinder No. 1, No. 2, No. 3 and No. 4).
  8. Be sure to confirm that no misfiring cylinder DTCs are stored again by conducting the confirmation driving pattern after the repairs.
  9. For 6 and 8 cylinder engines, the ECM intentionally does not store the specific misfiring cylinder DTCs at high engine speed. If misfires only occur during high engine speed driving, only DTC P0300 is stored. In the event of DTC P0300 being output, perform the following operations: Clear the DTCs. Refer to «DTC CHECK / CLEAR [05/2013 - 01/2014]»(ref-615120-S02653872462014050900000) . Start the engine and conduct the confirmation driving pattern. Read the misfiring rates of each cylinder or the DTCs using the Techstream. Repair the cylinders that have a high misfiring rate or are indicated by the DTCs. After finishing repairs, conduct the confirmation driving pattern again in order to verify that DTC P0300 is not stored.
  10. When one of Short FT #1 or Long FT #1 in the freeze frame data is outside the range of +/-15%, the air-fuel ratio may be rich (-15% or less) or lean (+15% or more).
  11. When Coolant Temp in the freeze frame data is below 75°C (167°F), the misfires may have occurred only while warming up the engine.
  12. An extremely imbalanced drive wheel which causes body vibration may cause misfire DTCs to be stored.

HINT

  1. Check the "Fuel Cut Elps Time" in the Data List or the Freeze Frame Data. If the elapsed time is over 0 seconds, then the engine speed is high (engine speed at which fuel cut occurs + 500 rpm). When this has happened, there is the possibility that the No. 1 valve rocker arm sub-assembly will become loose and a fire could start, so check that the No. 1 valve rocker arm sub-assembly is properly attached. Refer to «COMPONENTS [05/2013 - ]»(ref-615223-S34997177162014050900000) .
  2. By clearing the DTC, "Fuel Cut Elps Time" will be cleared.
  3. If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.
  4. Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  5. If misfire does not recur when the vehicle is brought to the workshop, reproduce the conditions stored in the ECM as freeze frame data.
  6. If the misfiring still cannot be reproduced even though the conditions stored in the ECM as freeze frame data have been reproduced, one of the following factors may be a cause of the problem: The fuel level is low. Improper fuel is being used. The spark plugs are dirty.
  7. After finishing repairs, check that no misfires occur in each cylinder (cylinder No. 1, No. 2, No. 3 and No. 4).
  8. Be sure to confirm that no misfiring cylinder DTCs are stored again by conducting the confirmation driving pattern after the repairs.
  9. For 6 and 8 cylinder engines, the ECM intentionally does not store the specific misfiring cylinder DTCs at high engine speed. If misfires only occur during high engine speed driving, only DTC P0300 is stored. In the event of DTC P0300 being output, perform the following operations: Clear the DTCs. Refer to «DTC CHECK / CLEAR [01/2014 - ]»(ref-615120-S08989089142014050900000) . Start the engine and conduct the confirmation driving pattern. Read the misfiring rates of each cylinder or the DTCs using the Techstream. Repair the cylinders that have a high misfiring rate or are indicated by the DTCs. After finishing repairs, conduct the confirmation driving pattern again in order to verify that DTC P0300 is not stored.
  10. When one of Short FT #1 or Long FT #1 in the freeze frame data is outside the range of +/-15%, the air-fuel ratio may be rich (-15% or less) or lean (+15% or more).
  11. When Coolant Temp in the freeze frame data is below 75°C (167°F), the misfires may have occurred only while warming up the engine.
  12. An extremely imbalanced drive wheel which causes body vibration may cause misfire DTCs to be stored.

HINT

Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

Scheme 142

Scheme 142: PROCEDURE
Scheme 142: PROCEDURE

Scheme 143

Scheme 143
Scheme 143
  1. INSPECT KNOCK SENSOR Disconnect the ECM connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition B30-87 (KNK1) - B30-110 (EKNK) 20°C (68°F) 120 to 280 kohms TEXT IN ILLUSTRATION *a Front view of wire harness connector (to ECM) NG --> See step 3 OK: Go to next step
  2. INSPECT ECM Disconnect the BM1 connector. Turn the ignition switch to ON. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Switch Condition Specified Condition BM1 female connector 1 - 5 Ignition switch ON 4.5 to 5.5 V TEXT IN ILLUSTRATION *1 Female *a Front view of wire harness connector (to ECM Wire) NG --> See step 4 OK --> See step 5
  3. CHECK HARNESS AND CONNECTOR (KNOCK SENSOR - ECM) Disconnect the ECM connector. Disconnect the knock sensor connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition M1-2 - B30-87 (KNK1) Always Below 1 ohms M1-1 - B30-110 (EKNK) Always Below 1 ohms M1-2 or B30-87 (KNK1) - Body ground Always 10 kohms or higher M1-1 or B30-110 (EKNK) - Body ground Always 10 kohms or higher HINT: Perform "Inspection After Repair" after replacing the knock sensor. Refer to «INITIALIZATION [05/2013 - ]»(ref-615120-S07565023022014050900000) . NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 6
  4. REPLACE ECM. Refer to «REMOVAL [05/2013 - 01/2014]»(ref-615228-S17169059992014050900000)
  5. CHECK FOR INTERMITTENT PROBLEMS. Refer to «CHECK FOR INTERMITTENT PROBLEMS [05/2013 - 01/2014]»(ref-615120-S09573425712014050900000)
  6. REPLACE KNOCK SENSOR. Refer to «REMOVAL [05/2013 - ]»(ref-615228-S16321977882014050900000)

HINT

Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

After performing the inspection procedure for the crankshaft position sensor, if DTC P0335 is output again, check the following items related to the camshaft position sensor.

  1. Installation condition of the camshaft position sensor
  2. Installation condition of the camshaft
  3. Connection of the camshaft position sensor connector

HINT

  1. If no problem is found by this diagnostic troubleshooting procedure, check for problems by referring to the engine mechanical Service Information.
  2. The engine speed can be checked by using the Techstream. To perform the check, follow the procedures below: Connect the Techstream to the DLC3. Start the engine. Turn the Techstream on. Enter the following menus: Powertrain / Engine / Data List / All Data / Engine Speed. The engine speed may be indicated as zero despite the engine running normally. This is caused by a lack of NE signals from the crankshaft position sensor. Alternatively, the engine speed may be indicated as less than the actual engine speed if the crankshaft position sensor output voltage is insufficient.
  3. Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

After performing the inspection procedure for the crankshaft position sensor, if DTC P0335 is output again, check the following items related to the camshaft position sensor.

  1. Installation condition of the camshaft position sensor
  2. Installation condition of the camshaft
  3. Connection of the camshaft position sensor connector

HINT

  1. If no problem is found by this diagnostic troubleshooting procedure, check for problems by referring to the engine mechanical Service Information.
  2. The engine speed can be checked by using the Techstream. To perform the check, follow the procedures below: Connect the Techstream to the DLC3. Start the engine. Turn the Techstream on. Enter the following menus: Powertrain / Engine / Data List / All Data / Engine Speed. The engine speed may be indicated as zero despite the engine running normally. This is caused by a lack of NE signals from the crankshaft position sensor. Alternatively, the engine speed may be indicated as less than the actual engine speed if the crankshaft position sensor output voltage is insufficient.
  3. Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

HINT

Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

CONDITIONING FOR SENSOR TESTING

HINT

Perform the operation with the engine speeds and time durations described below prior to checking the waveforms of the air fuel ratio and heated oxygen sensors. This is to activate the sensors sufficiently to obtain appropriate inspection results.

Scheme 144

Scheme 144: CONDITIONING FOR SENSOR TESTING
Scheme 144: CONDITIONING FOR SENSOR TESTING
  1. (a) Connect the Techstream to the DLC3.
  2. (b) Start the engine and warm it up with all the accessories switched off until the engine coolant temperature stabilizes.
  3. (c) Run the engine at an engine speed of between 2500 rpm and 3000 rpm for at least 3 minutes.
  4. (d) While running the engine at 3000 rpm for 2 seconds, and then 2000 rpm for 2 seconds, check the waveforms of the air fuel ratio and heated oxygen sensors using the Techstream.

HINT

  1. If the voltage output of either the air fuel ratio or heated oxygen sensor does not fluctuate, or there is noise in the waveform of either sensor, the sensor may be malfunctioning.
  2. If the voltage outputs of both the sensors remain lean or rich, the air-fuel ratio may be extremely lean or rich. In such cases, perform the Control the Injection Volume for A/F Sensor Active Test using the Techstream.
  3. If the Three-way Catalytic Converter (TWC) has deteriorated, the heated oxygen sensor (located behind the Three-way Catalytic Converter (TWC)) voltage output fluctuates up and down frequently, even under normal driving conditions (active air-fuel ratio control is not performed).
Engine Speed3000 rpm (without load)2000 rpm (during fuel-cut)2000 rpm (revving up the engine)
AFS Voltage B1S13.263 to 3.302 V4.996 V3.195 V
O2S B1S20.820 to 0.835 V0.015 V0.820 V

RESULT OF REAL-VEHICLE CHECK

Scheme 145

Scheme 145
Scheme 145

HINT

  1. If a malfunction cannot be found when troubleshooting DTC P0420, a lean or rich abnormality may be the cause. Perform troubleshooting by following the inspection procedure for P0171 (System Too Lean) and P0172 (System Too Rich).
  2. After performing repairs, drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern and check if DTC P0420 is output again. If a DTC is output again, replace the catalyst if it has not been replaced already.
  3. Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  4. Sensor 1 refers to the sensor closest to the engine assembly.
  5. Sensor 2 refers to the sensor farthest away from the engine assembly.

More articles — Engine Control System (Diagnostic Codes (P0128-P0420))