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Home >> Suzuki >> 2001 >> Vitara JS, 4D Utility, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0403: EGR Flow Malfunction >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Perform DTC CONFIRMATION TEST . If DTC P0403 is set, go to next step. If DTC P0403 is not set, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  2. Turn ignition off and disconnect EGR valve connector. Check for poor terminal contact at EGR valve connector. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, measure resistance of EGR valve. See EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. Replace as necessary and go to DTC CONFIRMATION TEST . If EGR valve resistance is okay, go to next step.
  3. Turn ignition off. Reconnect EGR valve connector. Disconnect PCM 26-pin connector C51-3 and PCM 30-pin connector C51-2. Check for poor terminal contact at PCM 26-pin connector C51-3 and PCM 30-pin connector C51-2. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, measure resistance between PCM 26-pin harness connector terminal No. 4 (Blue/Black wire) and following PCM 30-pin harness connector C51-2 terminals:
    • No. 13 (Light Green/Red wire).
    • No. 14 (Light Green/Yellow wire).
    • No. 15 (Light Green/White wire).
    • No. 16 (Light Green wire).

    Resistance at each terminal should be 20-24 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified at any terminal, repair open or short in suspect wire between PCM and EGR. See WIRING DIAGRAMS article. Go to DTC CONFIRMATION TEST .

  4. Check for continuity between ground and following PCM 30-pin harness connector C51-2 terminals:
    • No. 13 (Light Green/Red wire).
    • No. 14 (Light Green/Yellow wire).
    • No. 15 (Light Green/White wire).
    • No. 16 (Light Green wire).

    If continuity is present at any terminal, check for a short to ground in suspect wire between PCM 30-pin connector C51-2 and EGR. See WIRING DIAGRAMS article. Go to DTC CONFIRMATION TEST . If continuity is not present at all terminals, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article. If intermittent problem is not found, replace PCM and go to DTC CONFIRMATION TEST .

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