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Home >> Suzuki >> 2001 >> Esteem GL, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - Esteem 1.6L >> Diagnostic Tests >> DTC P0400: EGR Excessive Or Insufficient Flow >> 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. Turn ignition on. Wait a few seconds then turn ignition off. EGR stepper motor should operate for 0.6 second after switching ignition off. If operation is not as specified, go to step  5 . If operation is as specified, go to next step.
  3. Turn ignition on for 3 seconds. After 3 seconds, measure voltage (backprobe) between ground and appropriate terminals at ECM 26-pin harness connector C21. See EGR VOLTAGE SPECIFICATIONS  table. If readings are as specified, go to next step. If readings are not as specified, go to step  6 .
    EGR VOLTAGE SPECIFICATIONS

    Terminal No. Wire Color Volts
    8 Light Green/Red 10-14
    9 Red/Yellow 0-1
    21 Green/White 0-1
    22 Orange/Green 10-14
  4. Check EGR valve operation. See SYSTEM & COMPONENT TESTING article. Repair as necessary and go to DTC CONFIRMATION TEST  . If EGR valve operation is okay, check for plugged EGR valve or passage. Clean or replace as necessary. If EGR valve and passage are okay, replace ECM 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 (Red/Black wire) and No. 5 (Red/Black wire). See WIRING DIAGRAMS article. Reading should be 10-14 volts. If reading is as specified, go to next step. If reading is not as specified, check for short or open in Red/Black wire between main relay and EGR valve. See WIRING DIAGRAMS article. Repair as necessary and go to DTC CONFIRMATION TEST  .
  6. Check EGR valve operation. See SYSTEM & COMPONENT TESTING article. Repair as necessary and go to DTC CONFIRMATION TEST  . If EGR valve operation is okay, check for plugged EGR valve or passage. Clean or replace as necessary. If EGR valve and passage are okay, go to next step.
  7. Turn ignition off. Check for shorts or opens in Light Green/Red wire, Red/Yellow wire, Green/White wire and Orange/Green wire between EGR valve and ECM 26-pin connector C21. If wires are okay, check for a poor connector connection at ECM 26-pin connector C21 and EGR valve. If connectors are okay, replace ECM and go to DTC CONFIRMATION TEST  .
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