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Home >> Suzuki >> 2001 >> Esteem GL, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - Esteem 1.8L >> Diagnostic Tests >> DTC P0400: Excessive Or Insufficient EGR 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. If scan tool is not available, go to step  4 . If scan tool is available, turn ignition off. Connect scan tool. Start engine and allow it to reach normal operating temperature. With engine at idle, open EGR valve using MISC TEST mode on scan tool. EGR valve should open and engine idle speed should decrease. If EGR valve operates as specified, go to next step. If EGR valve does not operate as specified, go to step  4 .
  3. Check MDP sensor operation. See DTC P1408: OUTPUT VOLTAGE HIGHER OR LOWER THAN SPECIFICATION  . Repair or replace as necessary and go to DTC CONFIRMATION TEST  . If MDP sensor is okay, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article. If intermittent problem is not found, replace ECM and go to DTC CONFIRMATION TEST  .
  4. Turn ignition off. Disconnect EGR valve connector. Turn ignition on. Measure voltage between ground and EGR valve harness connector terminal No. 2 (Red/Black wire) and No. 5 (Red/Black wire), individually. If 10-14 volts are present at both terminals, turn ignition off and reconnect EGR valve connector. Go to next step. If 10-14 volts are not present at both terminals, repair open or short in Red/Black wire between EGR valve and main relay. See WIRING DIAGRAMS article.
  5. Ensure ignition is off. Disconnect ECM connectors. Measure resistance between ECM 35-pin harness connector E92 terminal No. 8 (Red/Black wire), and ECM 28-pin harness connector C20 terminals No. 3 (Light Green wire), No. 13 (Light Green/White wire), No. 14 (Light Green/Red wire) and No. 15 (Light Green/Yellow wire), individually. See Figure . If each resistance measurement is 20-24 ohms at 68°F (20°C), go to next step. If each resistance measurement is not 20-24 ohms at 68°F (20°C), check for open or short in circuit between ECM and EGR valve. See WIRING DIAGRAMS article.
  6. Check MDP sensor operation. See DTC P1408: OUTPUT VOLTAGE HIGHER OR LOWER THAN SPECIFICATION  . Repair or replace as necessary and go to DTC CONFIRMATION TEST  . If MDP sensor is okay, check for plugged EGR valve intake or exhaust passage. Go to next step.
  7. If EGR valve intake and exhaust passages are okay, check EGR valve operation. See SYSTEM & COMPONENT TESTING article. Repair or replace as necessary and go to DTC CONFIRMATION TEST  . 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 ECM and go to DTC CONFIRMATION TEST  .
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