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DTC P0441/16825 - EVAP Emission Control System Incorrect Purge Flow

NOTE: As a test, PCM triggers Leak Detection Pump (LDP) when EVAP canister purge regulator valve is open. Pressure should not build-up. If pressure builds-up, this DTC is set.
  1. Inspect EVAP system for kinks and/or pinched hoses. Repair hoses as necessary. If hoses were not repaired, go to next step. If hoses were repaired, erase DTC memory and test drive vehicle.
  2. Inspect EVAP system hose between EVAP canister and EVAP canister purge regulator valve. EVAP cansiter is located in spare tire well under cover. EVAP canister purge regulator valve is located on passenger side fender well in engine compartment. Repair hose as necessary. If hose was not repaired, go to next step. If hose was repaired, erase DTC memory and test drive vehicle.
  3. Inspect fuel system Leak Detection Pump (LDP) connecting hose. LDP is located in right rear wheelhousing behind a liner. Repair hose as necessary. If hose was not repaired, go to next step. If hose was repaired, erase DTC memory and test drive vehicle.
  4. Disconnect EVAP canister purge valve electrical connector. Using DVOM, check EVAP canister purge valve resistance. Measure resistance across EVAP canister purge valve terminals. Resistance should be 20-28 ohms. If resistance is within specification, go to next step. If resistance is not with specification, replace EVAP canister purge valve. Erase DTC memory and test drive vehicle.
  5. With ignition on, connect VAG 1527B voltage tester between EVAP canister purge valve harness connector terminal No. 1 and ground. Voltage tester should light up. If voltage tester lights up, go to next step. If voltage tester does not light up, check fuse for EVAP canister purge valve. If fuse is okay, go to next step. If fuse was replaced, erase DTC memory and test drive vehicle.
  6. Using a DVOM, check wiring between EVAP canister purge valve harness connector terminal No. 1 and fuse. See WIRING DIAGRAMS  section. If wiring is okay, check fuel pump relay and relay triggering. See SYSTEM/COMPONENT TESTS article. Go to next step.
  7. Connect VAG 1527B voltage tester between EVAP canister purge valve harness connector terminals. Using VAG 1551 scan tool, use OUTPUT DIAGNOSTIC TEST mode, function 03 to trigger EVAP canister purge valve. Voltage tester should flash. If voltage tester does not flash or lights up continuously, go to next step. If voltage tester flashes, ensure EVAP canister purge valve is not mechanically binding. Replace as necessary. Erase DTC memory and test drive vehicle.
  8. Turn ignition off. Disconnect Powertrain Control Module (PCM) connectors. Connect VAG 1598/19 test box to PCM wiring harness. Terminal assignments of test box are identical to PCM connectors "A", "B", "C", "D" and "E".
  9. Using DVOM, check resistance between EVAP canister purge valve harness connector terminal No. 2 and test box socket E12. Maximum resistance is one ohm. If resistance is within specification, go to next step. If resistance is not within specification, repair open or short circuit. Erase DTC memory and test drive vehicle. If an open or short circuit cannot be located, replace faulty PCM. Code new PCM and test drive vehicle. See PCM CODING  in this article.
  10. Replace fuel system LDP. Erase DTC memory and test drive vehicle.
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