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Home >> Suzuki >> 2003 >> XL-7 Base, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 4 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P0404: Exhaust Gas RECIRCULATION Range/Performance Open Valve >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Isuzu Trooper. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform ON-BOARD DIAGNOSTIC II SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD-II system check, go to next step.
  2. Turn ignition on. Review and record scan tool FAILURE RECORDS data. Operate vehicle within FAILURE RECORDS conditions. Using scan tool, monitor SPECIFIC DTC information for DTC P0404 until DTC P0404 test runs. If scan tool indicates DTC P0404 FAILED THIS IGNITION, go to next step. If scan tool does not indicate DTC P0404, see DIAGNOSTIC AIDS .
  3. Disconnect EGR valve 5-pin harness connector E-33. EGR valve is located at right rear of intake manifold. Check for poor, loose or corroded connections in EGR valve and harness connector. If problem is found, go to next step. If no problem is found, go to step  5.
  4. Repair or replace damaged terminals or connections. After repair is complete, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM.
  5. Remove EGR valve. Check for excessive carbon deposits on EGR valve shaft. If problem is found, go to next step. If no problem is found, go to step  7.
  6. Clean carbon from EGR valve. Inspect EGR valve for a bent shaft, damage to shaft or seat. If problem is found, go to step  8.
  7. Reinstall EGR valve. Start and run engine at idle. Using scan tool, use special functions to check EGR operation. On scan tool, press UP button to increase EGR from zero percent to 40 percent. If EGR operates correctly, system is okay. If EGR does not operate correctly, go to next step.
  8. Replace EGR valve. After repair is complete, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM. If DTC P0404 still fails SPECIFIC DTC test on scan tool, go to next step.
  9. Replace and reprogram PCM. See POWERTRAIN CONTROL MODULE REPLACEMENT  under POWERTRAIN CONTROL MODULE. Use scan tool to clear DTC and verify repair.
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