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Home >> Suzuki >> 2001 >> Vitara JS, 2D Utility, 1.6, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0400: EGR Flow Malfunction >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Perform DTC CONFIRMATION TEST . If DTC P0400 is set, go to next step. If DTC P0400 is not set, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  2. Check for DTC P0403. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTC P0403 is present, go to DTC P0403: EGR FLOW MALFUNCTION . If DTC P0403 is not present, go to next step.
  3. Is not using scan tool, go to  5. If using scan tool, check EGR valve operation. See EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EGR valve operation is okay, go to next step. If EGR valve operation is not okay, go to step  5.
  4. Check MAP sensor operation. See ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING article. Replace as necessary and go to DTC CONFIRMATION TEST . If MAP sensor operation is okay, 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 .
  5. Turn ignition off. Disconnect EGR valve connector. Turn ignition on. Measure voltage between ground and EGR valve harness connector terminals No. 2 (Blue/Black wire) and No. 5 (Blue/Black wire). If 10-14 volts are present at both wires, go to next step. If voltage is not present at either wire, repair open or short in suspect Blue/Black wire between main relay and EGR valve.
  6. Turn ignition off. Reconnect EGR valve connector. Disconnect PCM 26-pin connector C51-3 and PCM 30-pin connector C51-2. See Figure. 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, repair open or short in suspect wire between PCM and EGR. See WIRING DIAGRAMS article. Go to DTC CONFIRMATION TEST .

  7. Check MAP sensor operation. See ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING article. Replace as necessary and go to DTC CONFIRMATION TEST . If MAP sensor operation is okay, check for plugged EGR passage. If EGR passage is okay, check EGR valve malfunction. See EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EGR valve operation is okay, 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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