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Home >> Toyota >> 2003 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 14 (Engine Control System Self-Diagnostics) >> Diagnostic Tests >> DTC P0441: Incorrect EVAP Purge Flow, Or DTC P0446: EVAP Vent Control Malfunction >> Diagnosis & Repair
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Diagnosis & Repair

WARNING: This page is about a different car, the 2002 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
  1. If Toyota hand-held tester is available, go to next step. If Toyota hand-held tester is not available, go to step,  22.
  2. Check electrical connectors at EVAP VSV, vapor pressure sensor VSV and vapor pressure sensor for looseness, poor contact or for being disconnected. See Figure. If all electrical connectors are okay, go to next step. If any problem exists, repair or reconnect electrical connector as necessary.
  3. Check vacuum hoses to charcoal canister, vapor pressure sensor, vapor pressure sensor VSV and EVAP VSV for correct installation, loose connections, restrictions, disconnected hoses and damage. See Figure. If no problems exist, go to next step. If any problem exists, repair or replace components as necessary.
  4. Remove glove box for access to ECM with electrical connectors still installed on ECM. See Figure. Turn ignition on. Using voltmeter, check voltage between terminals No. 2 (Blue/Red wire) and No. 18 (Brown/White wire) at ECM electrical connector E6. See Figure. This is the VC and E2 terminals on ECM. Voltage should be 4.5-5.5 volts. If voltage is specification, go to next step. If voltage is not within specification, replace ECM.
  5. Turn ignition off. Connect voltmeter between terminals No. 18 (Brown/White wire) at ECM electrical connector E6 and No. 22 (Blue/Black wire) at ECM electrical connector E8 and with all electrical connectors installed on ECM. See Figure. This is the E2 and PTNK terminals on ECM. Disconnect vacuum hose from vapor pressure sensor. See Figure. Connect hand-held vacuum pump to vacuum hose fitting on vapor pressure sensor. Turn ignition on and note voltage reading with no vacuum applied on vapor pressure sensor. Using vacuum pump, apply 1.18 in. Hg of vacuum to vapor pressure sensor and note voltage reading. Voltage should be 2.9-3.7 volts without vacuum applied and .5 volt or less with vacuum applied. If voltage is not within specification, go to next step. If voltage is within specification, go to step  7.
  6. Check for open and short in wiring harness and electrical connectors between vapor pressure sensor and ECM. See WIRING DIAGRAMS article. If wiring harness and electrical connectors are okay, replace vapor pressure sensor. See VAPOR PRESSURE SENSOR under EMISSION SYSTEMS & SUB-SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - V6 & V8 article. If wiring harness or electrical connector is defective, repair as necessary.
  7. Connect hand-held tester to Data Link Connector (DLC) No. 3 at driver's side of instrument panel. See Figure. Turn ignition on and then turn hand-held tester on. Select ACTIVE TEST mode on hand-held tester. Disconnect vacuum hose at charcoal canister that goes back to the EVAP VSV. See Fig 1.
    Fig 1: Disconnecting Vacuum Hose At Charcoal Canister For EVAP Vacuum Switching Valve
    G00094853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  8. Start engine and allow engine to idle. Using hand-held tester, operate EVAP VSV and check for vacuum at disconnected vacuum hose at charcoal canister from EVAP VSV. When EVAP VSV is on, vacuum should exist and when EVAP VSV is off, no vacuum should exist if EVAP VSV is operating properly. If EVAP VSV does not operate properly, shut engine off. Go to next step. If EVAP VSV operates properly, reconnect vacuum hose, shut engine off and leave hand-held tester connected to DLC No. 3. Go to step  13.
  9. Check for damaged, disconnected or restricted vacuum hoses between EVAP VSV and throttle body, and between EVAP VSV and charcoal canister. If vacuum hoses are okay, go to next step. If vacuum hoses are damaged, disconnected or restricted, repair or replace vacuum hoses as necessary.
  10. Remove EVAP VSV. Using ohmmeter, ensure continuity exists between electrical terminals on EVAP VSV and resistance is 30-34 ohms at 68°F (20°C). Using ohmmeter, ensure no continuity exists between each electrical terminal and body of EVAP VSV. If EVAP VSV resistance is within specification and no continuity exists between electrical terminal and body of EVAP VSV, go to next step. If resistance is not within specification or if continuity exists between electrical terminal and body of EVAP VSV, replace EVAP VSV along with charcoal canister. Clean vacuum hoses between throttle body and EVAP VSV, and between EVAP VSV and charcoal canister.
  11. To test EVAP VSV operation, apply air pressure to port "E" on EVAP VSV. See Fig 2. Ensure air does not flow from port "F". Apply battery voltage and ground to electrical terminals on EVAP VSV. Apply air pressure to port "E" on EVAP VSV. Ensure air flows from port "F". If EVAP VSV operates properly, go to next step. If EVAP VSV does not operate properly, replace EVAP VSV along with charcoal canister. Clean vacuum hoses between throttle body and EVAP VSV, and between EVAP VSV and charcoal canister.
    Fig 2: Identifying EVAP Vacuum Switching Valve Ports
    G98E10201Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  12. Check for open and short in wiring harness and electrical connectors between EFI main relay and EVAP VSV, and between EVAP VSV and ECM. See WIRING DIAGRAMS article. EFI main relay may also be referred to as EFI relay. EFI main relay is located in fuse/relay box at driver's side front corner of engine compartment. If wiring harness and electrical connectors are okay, replace ECM. If wiring harness or electrical connector is defective, repair as necessary.
  13. Ensure ignition is on and then turn hand-held tester on. Select ACTIVE TEST mode on hand-held tester. Disconnect vacuum hoses at vapor pressure sensor VSV located on top of charcoal canister and note ports on vapor pressure sensor VSV. See Fig 3. Using hand-held tester, operate vapor pressure sensor VSV while applying air pressure to port "E" on vapor pressure sensor VSV. When vapor pressure sensor VSV is on, air should flow from port "F" and not from port "G". When vapor pressure sensor VSV is off, air should flow from port "G" and not from port "F". If vapor pressure sensor VSV does not operate as specified, turn ignition off. Go to next step. If vapor pressure sensor VSV operates as specified, turn ignition off and leave hand-held tester connected to DLC No. 3. Go to step  17.
    Fig 3: Locating Vapor Pressure Sensor Vacuum Switching Valve & Identifying Vapor Pressure Sensor Vacuum Switching Valve Ports
    G00094857Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  14. Disconnect electrical connector at vapor pressure sensor VSV. Using ohmmeter, ensure continuity exists between electrical terminals on vapor pressure sensor VSV and resistance is 37-44 ohms at 68°F (20°C). Using ohmmeter, ensure no continuity exists between each electrical terminal and body of vapor pressure sensor VSV. If vapor pressure sensor VSV resistance is within specification and no continuity exists between electrical terminal and body of vapor pressure sensor VSV, go to next step. If resistance is not within specification or if continuity exists between electrical terminal and body of vapor pressure sensor VSV, replace vapor pressure sensor VSV along with charcoal canister. Clean vacuum hoses between vapor pressure sensor VSV and charcoal canister, and between vapor pressure sensor VSV and vapor pressure sensor.
  15. To test vapor pressure sensor VSV operation, apply air pressure to port "E" on vapor pressure sensor VSV. See Fig 3. Air should flow from port "G" and not from port "F". Apply battery voltage and ground to electrical terminals on vapor pressure sensor VSV. Apply air pressure to port "E" on vapor pressure sensor VSV. Air should flow from port "F" and not from port "G". If vapor pressure sensor operates properly, go to next step. If vapor pressure sensor VSV does not operate properly, replace vapor pressure sensor VSV along with charcoal canister. Clean vacuum hoses between vapor pressure sensor VSV and charcoal canister, and between vapor pressure sensor VSV and vapor pressure sensor.
  16. Check for open and short in wiring harness and electrical connectors between EFI main relay and vapor pressure sensor VSV, and between vapor pressure sensor VSV and ECM. See WIRING DIAGRAMS article. EFI main relay may also be referred to as EFI relay. EFI main relay is located in fuse/relay box at driver's side front corner of engine compartment. If wiring harness and electrical connectors are okay, replace ECM. If wiring harness or electrical connector is defective, repair as necessary.
  17. Remove glove box for access to ECM with electrical connectors still installed on ECM. See Figure. Connect voltmeter between terminals No. 18 (Brown/White wire) at ECM electrical connector E6 and No. 22 (Blue/Black wire) at ECM electrical connector E8 and with all electrical connectors installed on ECM. See Figure. This is the E2 and PTNK terminals on ECM.
  18. Turn ignition on. Select ACTIVE TEST mode on hand-held tester. Ensure electrical connector is still disconnected at vapor pressure sensor VSV and electrical connector is installed on EVAP VSV. Start engine and allow engine to idle. Using hand-held tester, turn EVAP VSV on and note voltage reading. Voltage should be 2.0 volts or less. If voltage is not within specification, shut engine off and leave voltmeter connected. Go to next step. If voltage is within specification, shut engine off. Leave voltmeter connected and go to step  20.
  19. Check vacuum hoses between charcoal canister and vapor pressure sensor VSV, and between vapor pressure sensor VSV and vapor pressure sensor for correct installation, loose connections, restrictions, disconnected hoses and damage. If no problems exist, go to next step. If any problem exists, repair or replace components as necessary.
  20. Ensure voltmeter is still connected between terminals No. 18 (Brown/White wire) at ECM electrical connector E6 and No. 22 (Blue/Black wire) at ECM electrical connector E8 and with all electrical connectors installed on ECM. Remove fuel tank cap. Turn ignition on. Select ACTIVE TEST mode on hand-held tester. Disconnect electrical at vapor pressure sensor VSV. Start engine and allow engine to idle. Using hand-held tester, turn EVAP VSV on. Hold EVAP VSV on for at least 5 seconds. Using hand-held tester, turn EVAP VSV off. Wait 5 seconds after turning EVAP VSV off and note voltage reading. Voltage should be 2.5 volts or less. If voltage is within specification, go to next step. If voltage is not within specification, replace charcoal canister.
  21. Check charcoal canister. See appropriate FUEL EVAP SYSTEM TEST under FUEL EVAPORATIVE SYSTEM under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING - V6 & V8 article. If charcoal canister is okay, replace ECM. If charcoal canister is defective, replace charcoal canister.
  22. Check electrical connectors at EVAP VSV, vapor pressure sensor VSV and vapor pressure sensor for looseness, poor contact or for being disconnected. See Figure. If all electrical connectors are okay, go to next step. If any problem exists, repair or reconnect electrical connector as necessary.
  23. Check vacuum hoses to charcoal canister, vapor pressure sensor, vapor pressure sensor VSV and EVAP VSV for correct installation, loose connections, restrictions, disconnected hoses and damage. See Figure. If no problems exist, go to next step. If any problem exists, repair or replace components as necessary.
  24. Remove glove box for access to ECM with electrical connectors still installed on ECM. See Figure. Turn ignition on. Using voltmeter, check voltage between terminals No. 2 (Blue/Red wire) and No. 18 (Brown/White wire) at ECM electrical connector E6. See Figure. This is the VC and E2 terminals on ECM. Voltage should be 4.5-5.5 volts. If voltage is specification, go to next step. If voltage is not within specification, replace ECM.
  25. Turn ignition off. Connect voltmeter between terminals No. 18 (Brown/White wire) at ECM electrical connector E6 and No. 22 (Blue/Black wire) at ECM electrical connector E8 and with all electrical connectors installed on ECM. See Figure. This is the E2 and PTNK terminals on ECM. Disconnect vacuum hose from vapor pressure sensor. See Figure. Connect hand-held vacuum pump to vacuum hose fitting on vapor pressure sensor. Turn ignition on and note voltage reading with no vacuum applied on vapor pressure sensor. Using vacuum pump, apply 1.18 in. Hg of vacuum to vapor pressure sensor and note voltage reading. Voltage should be 2.9-3.7 volts without vacuum applied and .5 volt or less with vacuum applied. If voltage is not within specification, go to next step. If voltage is within specification, go to step  27.
  26. Check for open and short in wiring harness and electrical connectors between vapor pressure sensor and ECM. See WIRING DIAGRAMS article. If wiring harness and electrical connectors are okay, replace vapor pressure sensor. See VAPOR PRESSURE SENSOR under EMISSION SYSTEMS & SUB-SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - V6 & V8 article. If wiring harness or electrical connector is defective, repair as necessary.
  27. Disconnect vacuum hoses at EVAP VSV. See Figure. Turn ignition on. Connect jumper wire between body ground and terminal No. 7 (Blue/Black wire) at ECM electrical connector E6 to operate EVAP VSV. See Figure. This is the PRG terminal on ECM. With jumper wire connected so EVAP VSV is on, apply air pressure to port "E" on EVAP VSV. See Fig 2. Ensure air flows from port "F". Disconnect jumper wire so EVAP VSV is off. Apply air pressure to port "E" on EVAP VSV. Ensure air does not flow from port "F". If EVAP VSV does not operate as specified, turn ignition off. Go to next step. If EVAP VSV operates as specified, turn ignition off. Go to step  31.
  28. Remove EVAP VSV. Using ohmmeter, ensure continuity exists between electrical terminals on EVAP VSV and resistance is 30-34 ohms at 68°F (20°C). Using ohmmeter, ensure no continuity exists between each electrical terminal and body of EVAP VSV. If EVAP VSV resistance is within specification and no continuity exists between electrical terminal and body of EVAP VSV, go to next step. If resistance is not within specification or if continuity exists between electrical terminal and body of EVAP VSV, replace EVAP VSV along with charcoal canister. Clean vacuum hoses between throttle body and EVAP VSV, and between EVAP VSV and charcoal canister.
  29. To test EVAP VSV operation, apply air pressure to port "E" on EVAP VSV. See Fig 2. Ensure air does not flow from port "F". Apply battery voltage and ground to electrical terminals on EVAP VSV. Apply air pressure to port "E" on EVAP VSV. Ensure air flows from port "F". If EVAP VSV operates properly, go to next step. If EVAP VSV does not operate properly, replace EVAP VSV along with charcoal canister. Clean vacuum hoses between throttle body and EVAP VSV, and between EVAP VSV and charcoal canister.
  30. Check for open and short in wiring harness and electrical connectors between EFI main relay and EVAP VSV, and between EVAP VSV and ECM. See WIRING DIAGRAMS article. EFI main relay may also be referred to as EFI relay. EFI main relay is located in fuse/relay box at driver's side front corner of engine compartment. If wiring harness and electrical connectors are okay, replace ECM. If wiring harness or electrical connector is defective, repair as necessary.
  31. Disconnect vacuum hoses at vapor pressure sensor VSV located on top of charcoal canister. See Fig 3. Turn ignition on. Connect jumper wire between body ground and terminal No. 21 (Blue wire) at ECM electrical connector E8 to operate vapor pressure sensor VSV. See Figure. This is the TPC terminal on ECM.
  32. With jumper wire connected so vapor pressure sensor VSV is on, apply air pressure to port "E" on vapor pressure sensor VSV. See Fig 3. Ensure air flows from port "F" and not from port "G". Disconnect jumper wire so vapor pressure sensor is off. Apply air pressure to port "E" on vapor pressure sensor VSV. Ensure air flows from port "G" and not from port "F". If vapor pressure sensor VSV does not operate as specified, turn ignition off and remove jumper wire. Go to next step. If vapor pressure sensor VSV operates as specified, turn ignition off and remove jumper wire. Check for defective charcoal canister. See appropriate FUEL EVAP SYSTEM TEST under FUEL EVAPORATIVE SYSTEM under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING - V6 & V8 article. If charcoal canister is defective, replace charcoal canister.
  33. Disconnect electrical connector at vapor pressure sensor VSV. Using ohmmeter, ensure continuity exists between electrical terminals on vapor pressure sensor VSV and resistance is 37-44 ohms at 68°F (20°C). Using ohmmeter, ensure no continuity exists between each electrical terminal and body of vapor pressure sensor VSV. If resistance is within specification and no continuity exists between electrical terminal and body of vapor pressure sensor VSV, go to next step. If resistance is not within specification or if continuity exists between electrical terminal and body of vapor pressure sensor VSV, replace vapor pressure sensor VSV along with charcoal canister. Clean vacuum hoses between vapor pressure sensor VSV and charcoal canister, and between vapor pressure sensor VSV and vapor pressure sensor.
  34. To test vapor pressure sensor VSV operation, apply air pressure to port "E" on vapor pressure sensor VSV. See Fig 3. Air should flow from port "G" and not from port "F". Apply battery voltage and ground to electrical terminals on vapor pressure sensor VSV. Apply air pressure to port "E" on vapor pressure sensor VSV. Air should flow from port "F" and not from port "G". If vapor pressure sensor operates properly, go to next step. If vapor pressure sensor VSV does not operate properly, replace vapor pressure sensor VSV along with charcoal canister. Clean vacuum hoses between vapor pressure sensor VSV and charcoal canister, and between vapor pressure sensor VSV and vapor pressure sensor.
  35. Check for open and short in wiring harness and electrical connectors between EFI main relay and vapor pressure sensor VSV, and between vapor pressure sensor VSV and ECM. See WIRING DIAGRAMS article. EFI main relay may also be referred to as EFI relay. EFI main relay is located in fuse/relay box at driver's side front corner of engine compartment. If wiring harness and electrical connectors are okay, replace ECM. If wiring harness or electrical connector is defective, repair as necessary.
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