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Home >> Pontiac >> 2002 >> Aztek FWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing >> Fuel System (Diesel) >> Water-In-Fuel Light Inoperative (6.6L) >> Diagnostic Procedure
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Diagnostic Procedure

  1. Perform Diagnostic System Check - Engine Controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 6.6L SIERRA & SILVERADO article. After performing Diagnostic System Check - Engine Controls, go to next step.
  2. Turn ON the ignition, with the engine OFF. Does battery indicator illuminate in message center in Instrument Panel Cluster? If yes, go to next step. If no, go to DIAGNOSTIC SYSTEM CHECK - INSTRUMENT CLUSTER under SELF-DIAGNOSTIC SYSTEM in appropriate ANALOG INSTRUMENT PANEL article.
  3. Start and run engine. Does message center in IPC indicate water-in-fuel? If yes, go to WATER-IN-FUEL DRAINING PROCEDURE (6.6L) . If no, go to next step.
  4. Observe Water-In-Fuel parameter of scan tool. Does scan tool indicate light is being commanded ON? If yes, go to step  13. If no, go to next step.
  5. Disconnect water-in-fuel sensor. Connect a 3-amp fused jumper wire between Control circuit and Ground circuit of water-in-fuel sensor. Does scan tool indicate light is being commanded ON? If yes, go to step  10. If no, go to next step.
  6. Connect a 3-amp fused jumper wire between Control circuit of water-in-fuel sensor and a good ground. Does scan tool indicate light is being commanded ON? If yes, go to step  9. If no, go to next step.
  7. Test Control circuit of water-in-fuel sensor for an open. Did you find a problem? If yes, go to next step. If no, go to step  11.
  8. Repair open in Water-In-Fuel Sensor Control circuit. After repairs, go to step  14.
  9. Repair open condition in Water-In-Fuel Sensor Ground circuit. After repairs, go to step  14.
  10. Inspect the connections at the water-in-fuel sensor. Repair as necessary. Did you find and correct the condition? If yes, go to step  14. If no, go to step  12.
  11. Inspect connections at ECM. Repair as necessary. Did you find and correct the condition? If yes, go to step  14. If no, go to step  13.
  12. Replace water-in-fuel sensor. After repairs, go to step  14.
  13. Replace ECM. Perform ECM relearn procedures. See PROGRAMMING in SELF-DIAGNOSTICS - 6.6L SIERRA & SILVERADO article. After repairs, go to next step.
  14. Operate system in order to verify repair. Did you correct the condition? If yes, system is okay. If no, go to step  1.
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