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Home >> Suzuki >> 2002 >> XL-7 Plus >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0446: EVAP Control System - Vent Valve Control Circuit Malfunction >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. If engine system check has been performed, go to next step. If engine system check has not been performed, go to A4: ENGINE SYSTEM CHECK  under SYSTEM TESTS.
  2. Check EVAP-CVV circuit operation. See EVAP CANISTER VENT VALVE CIRCUIT under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EVAP-CVV and circuit operation is as specified, go to next step. If EVAP-CVV and circuit operation is not as specified, go to step  5.
  3. Check EVAP canister for damage or clogged passages. See EVAP CANISTER under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EVAP canister operation is as specified, go to next step. If EVAP canister operation is not as specified, replace EVAP canister. After repair, repeat DTC CONFIRMATION TEST .
  4. Check EVAP canister air filter and passages for damage or clogging. If problem is found, clean or replace filter as necessary. After repair, repeat DTC CONFIRMATION TEST . If no problem is found with EVAP system, problem is probably intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. If intermittent problem is not found, substitute a known good ECM and repeat DTC CONFIRMATION TEST .
  5. Check EVAP-CVV operation. See EVAP CANISTER VENT VALVE under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EVAP-CVV operation is as specified, go to next step. If EVAP-CVV operation is not as specified, replace EVAP-CVV. After repair, repeat DTC CONFIRMATION TEST .
  6. Check for open or short in Blue/Black wire between EVAP-CVV, main relay and ECM. See WIRING DIAGRAMS article. Also, check for open or short in Purple/Red wire between EVAP-CVV and ECM. If problem is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST . If no problem with wiring is found, go to next step.
  7. Substitute a known good ECM, and repeat DTC CONFIRMATION TEST . If DTC does not reset, testing is complete.
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