DTC P0443 2ZR-FXE

DTC P0443 Evaporative Emission Control System Purge Control Valve Circuit

  1. Description

  2. Confirmation driving pattern

  3. Wiring diagram

  4. Inspection procedure

  5. Perform active test using intelligent tester (activate the vsv for evap control)

  6. Inspect purge vsv

  7. Check purge vsv (power source voltage)

  8. Check harness and connector (purge vsv - ecm)

Description

To reduce hydrocarbon (HC) emissions, evaporated fuel from the fuel tank is routed through the canister to the intake manifold for combustion in the cylinders. The ECM changes the duty signal to the purge VSV so that the intake quantity of hydrocarbon (HC) emissions is appropriate for the driving conditions (engine load, engine speed, vehicle speed, etc.) after the engine is warmed up.

DTC No. DTC Detection Condition Trouble Area
P0443 All of the following conditions (a) and (b) are met (1 trip detection logic): (a) The target control value and actual control value do not match for 10 seconds or more (b) The target control value and actual control value do not match for 80 times or more
  1. Open or short in purge VSV circuit
  2. Purge VSV
  3. ECM

Confirmation driving pattern

Lexus DTC P0443 Confirmation driving pattern
  1. Connect the intelligent tester to the DLC3.
  2. Turn the power switch on (IG) and turn the tester on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation).
  4. Turn the power switch off and wait for at least 30 seconds.
  5. Turn the power switch on (IG) and turn the tester on.
  6. Put the engine in inspection mode (maintenance mode) .
  7. Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher [A].

    HINT:

    The A/C switch and all accessory switches should be off.

  8. Idle the engine for 15 minutes or more [B].

    HINT:

    Check the EVAP (Purge) VSV item in the Data List. When the value of this item is between 5 and 95%, the judgment will be performed.

  9. Enter the following menus: Powertrain / Engine and ECT / DTC [C].
  10. Read the pending DTCs.

    HINT:

    1. If a pending DTC is output, the system is malfunctioning.
    2. If a pending DTC is not output, perform the following procedure.
  11. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  12. Input the DTC: P0443.
  13. Check the DTC judgment result.
    Tester Display Description
    NORMAL
    1. DTC judgment completed
    2. System normal
    ABNORMAL
    1. DTC judgment completed
    2. System abnormal
    INCOMPLETE
    1. DTC judgment not completed
    2. Perform driving pattern after confirming DTC enabling conditions
    UNKNOWN
    1. Unable to perform DTC judgment
    2. Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    HINT:

    1. If the judgment result shows NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
    3. If the judgment result shows INCOMPLETE or UNKNOWN, perform the following procedure.
  14. Drive the vehicle at a constant speed between 40 and 60 km/h (25 and 37 mph) for 10 minutes [D].

    CAUTION:

    When performing the confirmation driving pattern, obey all speed limits and traffic laws.

  15. Check the DTC judgment result [E].

Wiring diagram

Lexus DTC P0443 Wiring diagram

Inspection procedure

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.

1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (ACTIVATE THE VSV FOR EVAP CONTROL)

Lexus DTC P0443 Connect the intelligent tester to the DLC3.

  1. Connect the intelligent tester to the DLC3.

  1. Disconnect the canister side vacuum hose from the purge VSV.

  1. Turn the power switch on (IG) and turn the tester on.

  1. Put the engine in inspection mode (maintenance mode) .

  1. Start the engine.

  1. Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the VSV for Evap Control.

  1. Check if air is sucked into the port when operating the purge VSV using the tester.

    OK
    Tester Operation Specified Condition
    ON (Purge VSV is on) Suction of air
    OFF (Purge VSV is off) No suction of air
  NG  
Go to step 2
 
OK  
   
CHECK FOR INTERMITTENT PROBLEMS

2.INSPECT PURGE VSV
  1. Inspect the purge VSV .

  NG  
REPLACE PURGE VSV
 
OK  
   

3.CHECK PURGE VSV (POWER SOURCE VOLTAGE)

Lexus DTC P0443 Disconnect the purge VSV connector.

  1. Disconnect the purge VSV connector.

  1. Turn the power switch on (IG).

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:

    Tester Connection Switch Condition Specified Condition
    D11-2 - Body ground Power switch on (IG) 11 to 14 V
    Text in Illustration
    *a Front view of wire harness connector (to Purge VSV)
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR (PURGE VSV - EFI MAIN RELAY)
 
OK  
   

4.CHECK HARNESS AND CONNECTOR (PURGE VSV - ECM)
  1. Disconnect the purge VSV connector.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:

    Tester Connection Condition Specified Condition
    D11-1 - D27-28 (PRG) Always Below 1 ?
    D11-1 or D27-28 (PRG) - Body ground Always 10 k? or higher
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   
REPLACE ECM