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Engine Control (Sfi) System (Dtcs P0420 - U0101 & Circuit Tests): Wiring Lexus IS II facelift

Testing & Diagnostics 17 illustrations ~2750 words

WIRING DIAGRAM

Refer to DTC P2102. Refer to WIRING DIAGRAM .

Refer to DTC P2102. Refer to WIRING DIAGRAM .

Refer to DTC P2120. Refer to WIRING DIAGRAM .

Refer to DTC P2195. Refer to WIRING DIAGRAM .

Refer to DTC P2195. Refer to WIRING DIAGRAM .

Refer to DTC P0450. Refer to WIRING DIAGRAM .

Refer to ECM Power Source Circuit. Refer to WIRING DIAGRAM .

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Scheme 136: PROCEDURE
Scheme 136: PROCEDURE
  1. CHECK MIL Check that Malfunction Indicator Lamp (MIL) lights up when turning the engine switch on (IG). OK MIL lights up. OK --> SYSTEM OK NG: Go to next step
  2. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM Connect Techstream to the DLC3. Turn the engine switch on (IG) and tester on. Check the communication between the tester and ECM. Result Result Proceed to Communication is possible A Communication is not possible B A --> GO TO MIL CIRCUIT B: Go to next step
  3. CHECK THROTTLE BODY ASSEMBLY (CHECK MIL ILLUMINATED) Disconnect the throttle body connector. Turn the engine switch on (IG). Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the throttle body connector. A --> REPLACE THROTTLE BODY ASSEMBLY B: Go to next step
  4. CHECK ACCELERATOR PEDAL ASSEMBLY (CHECK MIL ILLUMINATED) Disconnect the accelerator pedal position sensor connector. Turn the engine switch on (IG). Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the accelerator pedal position sensor connector. A --> REPLACE ACCELERATOR PEDAL ASSEMBLY B: Go to next step
  5. CHECK VVT SENSOR FOR INTAKE CAMSHAFT BANK 1 (CHECK MIL ILLUMINATED) Disconnect the VVT sensor for intake camshaft bank 1 connector. Turn the engine switch on (IG). Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the VVT sensor for intake camshaft bank 1 connector. A --> REPLACE VVT SENSOR FOR INTAKE CAMSHAFT BANK 1 B: Go to next step
  6. CHECK VVT SENSOR FOR EXHAUST CAMSHAFT BANK 1 (CHECK MIL ILLUMINATED) Disconnect the VVT sensor for exhaust camshaft bank 1 connector. Turn the engine switch on (IG). Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the VVT sensor for exhaust camshaft bank 1 connector. A --> REPLACE VVT SENSOR FOR EXHAUST CAMSHAFT BANK 1 B: Go to next step
  7. CHECK VVT SENSOR FOR INTAKE CAMSHAFT BANK 2 (CHECK MIL ILLUMINATED) Disconnect the VVT sensor for intake camshaft bank 2 connector. Turn the engine switch on (IG). Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the VVT sensor for intake camshaft bank 2 connector. A --> REPLACE VVT SENSOR FOR INTAKE CAMSHAFT BANK 2 B: Go to next step
  8. CHECK VVT SENSOR FOR EXHAUST CAMSHAFT BANK 2 (CHECK MIL ILLUMINATED) Disconnect the VVT sensor for exhaust camshaft bank 2 connector. Turn the engine switch on (IG). Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the VVT sensor for exhaust camshaft bank 2 connector. A --> REPLACE VVT SENSOR FOR EXHAUST CAMSHAFT BANK 2 B: Go to next step
  9. CHECK FUEL PRESSURE SENSOR (CHECK MIL ILLUMINATED) Disconnect the fuel pressure sensor connector. Turn the engine switch on (IG). Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the fuel pressure sensor connector. A --> REPLACE FUEL PRESSURE SENSOR B: Go to next step
  10. CHECK CHARCOAL CANISTER ASSEMBLY (CHECK MIL ILLUMINATED) Disconnect the canister pump module connector. Turn the engine switch on (IG). Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the canister pump module connector. A --> REPLACE CHARCOAL CANISTER ASSEMBLY B: Go to next step
  11. CHECK HARNESS AND CONNECTOR Disconnect the throttle body connector. Disconnect the accelerator pedal position sensor connector. Disconnect the VVT sensor for intake camshaft bank 1 connector. Disconnect the VVT sensor for exhaust camshaft bank 1 connector. Disconnect the VVT sensor for intake camshaft bank 2 connector. Disconnect the VVT sensor for exhaust camshaft bank 2 connector. Disconnect the fuel pressure sensor connector. Disconnect the canister pump module connector. Disconnect the E3, E5 and A6 ECM connectors. Measure the resistance according to the value(s) in the table below. Standard resistance (Check for short) Tester Connections Specified Conditions VC (E3-29) - Body ground 10 kohms or higher VC2 (E5-29) - Body ground 10 kohms or higher VCPA (A6-35) - Body ground 10 kohms or higher VCP2 (A6-27) - Body ground 10 kohms or higher Reconnect the ECM connectors. Reconnect the canister pump module connector. Reconnect the fuel pressure sensor connector. Reconnect the VVT sensor for exhaust camshaft bank 2 connector. Reconnect the VVT sensor for intake camshaft bank 2 connector. Reconnect the VVT sensor for exhaust camshaft bank 1 connector. Reconnect the VVT sensor for intake camshaft bank 1 connector. Reconnect the accelerator pedal position sensor connector. Reconnect the throttle body connector. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE ECM

Refer to DTC P0230. Refer to WIRING DIAGRAM .

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Scheme 137: PROCEDURE

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  1. CHECK FUEL PUMP (FUEL PUMP OPERATION) Check if there is pressure in the fuel inlet hose. HINT: If there is fuel pressure, you will hear the sound of fuel flowing. OK --> See step 12 NG: Go to next step
  2. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CIRCUIT OPENING RELAY) Connect Techstream to the DLC3. Turn the engine switch on (IG) and turn Techstream on. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed. Check the operation of the relay while operating it using Techstream. OK Operating noise can be heard from the relay. OK --> See step 8 NG: Go to next step
  3. INSPECT ECM POWER SOURCE CIRCUIT NG --> REPAIR OR REPLACE POWER SOURCE CIRCUIT OK: Go to next step
  4. INSPECT FUSE (F/PMP FUSE) Remove the F/PMP fuse from the engine room J/B No. 2. Measure the resistance of the F/PMP fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  5. INSPECT INTEGRATION NO. 1 RELAY (EFI NO. 2 RELAY) Remove the integration relay from the engine room J/B No. 2. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Specified Condition 2B-4 - 2C-1 10 kohms or higher 2B-4 - 2C-1 Below 1 ohms (when battery voltage applied to terminals 2B-3 and 2B-2) NG --> REPLACE INTEGRATION NO. 1 RELAY OK: Go to next step
  6. INSPECT INTEGRATION NO. 1 RELAY (C/OPN RELAY) Remove the integration relay from the engine room J/B No. 2. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Specified Condition 2B-6 - 2B-8 10 kohms or higher 2B-6 - 2B-8 Below 1 ohms (when battery voltage applied to terminals 2B-6 and 2B-7) NG --> REPLACE INTEGRATION NO. 1 RELAY OK: Go to next step
  7. INSPECT ECM (FC VOLTAGE) Turn the engine switch on (IG). Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Specified Condition FC (A5-14) - E1 (E4-7) 9 to 14 V OK --> REPLACE ECM NG --> CHECK AND REPAIR HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY)
  8. INSPECT F/PMP RELAY Remove the F/PMP relay from the engine room R/B No. 2. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Specified Condition 3 - 4 10 kohms or higher 3 - 4 Below 1 ohms (when battery voltage applied to terminals 1 and 2) NG --> REPLACE F/PMP RELAY OK: Go to next step
  9. INSPECT FUEL PUMP Inspect fuel pump resistance. Measure the resistance between terminals 4 and 5. Standard resistance 0.2 to 3.0 ohms at 20°C (68°F) Inspect fuel pump operation. Apply battery voltage to both terminals. Check that the pump operates. NOTE: These tests must be done quickly (within 10 seconds) to prevent the coil from burning out. Keep the fuel pump as far away from the battery as possible. Always switch at the battery side. NG --> REPLACE FUEL PUMP OK: Go to next step
  10. CHECK HARNESS AND CONNECTOR (FUEL PUMP - F/PMP RELAY) Check the harness and the connectors between the fuel pump and the F/PMP relay. Disconnect the fuel pump connector. Remove the F/PMP relay from the engine room R/B No. 2. Measure the resistance according to the value(s) in the table below. Standard resistance (Check for open) Tester Connection Specified Condition Fuel pump (Q14-4) - F/PMP relay (4) Below 1 ohms Standard resistance (Check for short) Tester Connection Specified Condition Fuel pump (Q14-4) or F/PMP (4) - Body ground 10 kohms or higher Check the harness and the connectors between the fuel pump and body ground. Disconnect the fuel pump connector. Measure the resistance according to the value(s) in the table below. Standard resistance (Check for open) Tester Connection Specified Condition Fuel pump (Q14-5) - Body ground 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  11. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - F/PMP RELAY) Remove the integration relay from the engine room R/B No. 2. Remove the F/PMP relay from the engine room R/B No. 2. Measure the resistance according to the value(s) in the table below. Standard resistance (Check for open) Tester Connection Specified Condition Integration relay (2B-8) - F/PMP relay (1) Below 1 ohms Integration relay (2B-8) - F/PMP relay (3) Below 1 ohms Standard resistance (Check for short) Tester Connection Specified Condition Integration relay (2B-8) or F/PMP relay (1) - Body ground 10 kohms or higher Integration relay (2B-8) or F/PMP relay (3) - Body ground 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPAIR OR REPLACE INTEGRATION NO. 1 RELAY
  12. INSPECT F/PMP RELAY Remove the F/PMP relay from the engine room R/B No. 2. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Specified Condition 3 - 4 10 kohms or higher 3 - 4 Below 1 ohms (when battery voltage applied to terminals 1 and 2) NG --> REPLACE F/PMP RELAY OK: Go to next step
  13. INSPECT FUEL PUMP RESISTER Measure the resistance of the fuel pump resistor. Standard resistance 0.30 to 0.34 ohms at 20°C (68°F) NG --> REPLACE FUEL PUMP RESISTER OK: Go to next step
  14. CHECK HARNESS AND CONNECTOR (F/PMP RELAY - FUEL PUMP RESISTER) Check the harness and the connectors between the F/PMP relay and the fuel pump resistor. Remove the F/PMP relay from the engine room R/B No. 2. Disconnect the fuel pump resistor connector. Measure the resistance according to the value(s) in the table below. Standard resistance (Check for open) Tester Connection Specified Condition F/PMP relay (4) - Fuel pump resistor (A40-2) Below 1 ohms F/PMP relay (3) - Fuel pump resistor (A40-1) Below 1 ohms Standard resistance (Check for short) Tester Connection Specified Condition Fuel pump relay (4) or Fuel pump resistor (A40-2) - Body ground 10 kohms or higher Fuel pump relay (3) or Fuel pump resistor (A40-1) - Body ground 10 kohms or higher OK --> PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR

Refer to DTC P0617. Refer to WIRING DIAGRAM .

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  1. CHECK CRANKING When starting the engine, check whether the starter motor starts. OK --> CHECK FOR INTERMITTENT PROBLEMS NG: Go to next step
  2. READ VALUE USING TECHSTREAM (STA SIGNAL) Connect Techstream to the DLC3. Turn the engine switch on (IG) and turn the tester on. Enter the following menus: Powertrain / Engine and ECT / Data List / Starter Signal. Check the result when the engine switch is turned on (IG) and the engine is started. Standard Engine Switch Position ON (IG) ENGINE START Starter Signal OFF ON OK --> See step 6 NG: Go to next step
  3. INSPECT ECM (STAR AND STSW VOLTAGE) Measure the voltage according to the value(s) in the table below while cranking the engine. Standard voltage Tester Connection Specified Condition STAR (E4-4) - E1 (E4-7) 9 to 14 V STSW (A5-19) - E1 (E4-7) 9 to 14 V Result Terminal STAR Terminal STSW Proceed to 9 to 14 V 9 to 14 V A 0 V 9 to 14 V B 0 V 0 V C C --> See step 10 B --> REPLACE ECM A: Go to next step
  4. INSPECT ST CUT RELAY Remove the ST CUT relay from the engine room R/B No. 2. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Specified Condition 3 - 5 10 kohms or higher 3 - 5 Below 1 ohms (when battery voltage applied to terminals 1 and 2) NG --> REPLACE ST CUT RELAY OK: Go to next step
  5. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY (A/T) OR CLUTCH PEDAL SWITCH ASSEMBLY (M/T) Disconnect the park/neutral position (PNP) switch (A/T) or clutch pedal switch (M/T) connector. Measure the resistance according to the value(s) in the table below. Standard resistance (A/T) Shift Position Tester Connection Specified Condition P 4 - 5 Below 1 ohms N 4 - 5 Below 1 ohms Standard resistance (M/T) Clutch Pedal Operation Tester Connection Specified Condition Depressed 1 - 2 Below 1 ohms NG --> REPLACE PARK/NEUTRAL POSITION SWITCH (A/T) OR CLUTCH PEDAL SWITCH (M/T) OK --> CHECK AND REPAIR HARNESS AND CONNECTOR ((PARK/NEUTRAL POSITION SWITCH - ECM, ECM - ST CUT RELAY, ST)
  6. INSPECT STARTER RELAY Remove the STARTER relay from the engine room R/B No. 1. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Specified Condition 3 - 5 10 kohms or higher 3 - 5 Below 1 ohms (when battery voltage applied to terminals 1 and 2) NG --> REPLACE STARTER RELAY OK: Go to next step
  7. CHECK HARNESS AND CONNECTOR (PNP SWITCH (A/T) OR CLUTCH PEDAL SWITCH (M/T) - ST RELAY) Check the harness and the connectors between the park/neutral position switch and the starter relay. Disconnect the E45*1, A24*2 switch connector. *1: A/T *2: M/T Remove the starter relay from the engine room R/B No. 1. Measure the resistance according to the value(s) in the table below. Standard resistance (A/T) (Check for open) Tester Connection Specified Condition Park/Neutral position switch (E45-5) - STARTER relay (1) Below 1 ohms Standard resistance (M/T) (Check for open) Tester Connection Specified Condition Clutch pedal switch (A24-2) - STARTER relay (1) Below 1 ohms Standard resistance (A/T) (Check for short) Tester Connection Specified Condition Park/Neutral position switch (E45-5) or STARTER relay (1) - Body ground 10 kohms or higher Standard resistance (M/T) (Check for short) Tester Connection Specified Condition Clutch pedal switch (A24-2) or STARTER relay (1) - Body ground 10 kohms or higher Check the harness and the connector between the starter relay and the body ground. Remove the starter relay from the engine room R/B No. 1. Measure the resistance according to the value(s) in the table below. Standard resistance (Check for open) Tester Connection Specified Condition STARTER relay (2) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  8. INSPECT ENGINE ROOM RELAY BLOCK (STARTER RELAY VOLTAGE) Remove the starter relay from the engine room R/B No. 1. Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Specified Condition STARTER relay (5) - Body ground 9 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  9. INSPECT STARTER ASSEMBLY NG --> REPAIR OR REPLACE STARTER ASSEMBLY OK --> REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER RELAY - STARTER, STARTER - BATTERY)
  10. CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - ECM) Check the harness and the connectors between the power source control ECU and ECM. Disconnect the power source control ECU connector. Disconnect the A5 ECM connector. Measure the resistance according to the value(s) in the table below. Standard resistance (Check for open) Tester Connection Specified Condition J55-39 (STSW) - A5-19 (STSW) Below 1 ohms Standard resistance (Check for short) Tester Connection Specified Condition J55-39 (STSW) or A5-19 (STSW) - Body ground 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START

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