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Home >> Isuzu >> 2000 >> Rodeo S, 2.2 D >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 2.2L >> Diagnostic Trouble Code Identification >> DTC P0405: EGR Sensor Circuit Low >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform On-Board Diagnostic II (OBD-II) system check. See SELF-DIAGNOSTICS - INTRODUCTION article. Go to next step.
  2. Turn ignition on. Command EGR valve percentage to 25, 50, 75 and 100, while observing EGR valve position. If actual EGR valve position follows the desired EGR position, go to step  15. If EGR actual position is different than EGR desired position, go to next step.
  3. Using a DVOM connected to ground, probe EGR 5-volt reference circuit. If reading is about 5 volts, go to next step. If reading is not about 5 volts, go to step  5.
  4. Turn ignition off. Using a jumper wire, connect EGR valve harness connector 5-volt reference circuit to signal circuit. Turn ignition on. If actual EGR position reading on scan tool is 100 percent, go to step  6. If actual EGR position reading is not 100 percentage, go to step  7.
  5. Using a test light connected to battery voltage, probe EGR 5-volt reference circuit. If test light illuminates, go to step  8. If test light does not illuminate, go to step  9.
  6. Check EGR 5-volt reference circuit and signal circuit for poor connection at PCM and EGR valve harness connectors. Repair as necessary. Go to step  15. If all connectors are okay, go to step  10.
  7. Using a test light connected to battery voltage, probe EGR signal circuit. If test light illuminates, go to step  11. If test light does not illuminate, go to step  12.
  8. Check for short to ground in EGR 5-volt reference circuit. Repair as necessary and go to step  15. If short does not exist, go to step  13.
  9. Check for an open in EGR 5-volt reference circuit. Repair as necessary and go to step  15. If an open does not exist, go to step  14.
  10. Replace EGR valve. Go to step  15.
  11. Check for short to ground in EGR signal circuit. Repair as necessary and go to step  15. If short does not exist, go to step  13.
  12. Check for an open in EGR signal circuit. Repair as necessary and go to step  15. If an open does not exist, go to next step.
  13. Replace and reprogram PCM using required equipment. See PROGRAMMING . Go to step  15.
  14. Turn ignition off. Disconnect PCM harness connectors. Check for poor connections at EGR valve circuit terminals of PCM and PCM harness connector. Repair as necessary and go to next step. If PCM and PCM harness connector terminals are okay, go to step  13.
  15. Using scan tool, clear DTCs. Start engine and idle to normal operating temperature. Operate vehicle within conditions for setting DTC P0405. See CIRCUIT DESCRIPTION . If scan tool indicates diagnostic RAN AND PASSED, system is okay. If scan tool indicates diagnostic did not pass, go to step  2.
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