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Home >> Isuzu >> 2000 >> Rodeo LSE, 2.2 D >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 2.2L >> Diagnostic Trouble Code Identification >> DTC P1133: Ho2S Insufficient Switching Sensor 1 >> 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. Using scan tool, record any other failed DTCs. If any other DTCs are set, diagnose affected DTC before proceeding. If no other DTC sets, start engine and allow it to idle. Operate vehicle within conditions required to set DTC. Using scan tool, read specified DTC. If scan tool displays DTC P1133 FAILED THIS IGN, go to next step. If scan tool does not display DTC P1133 FAILED THIS IGN, go to DIAGNOSTIC AIDS .
  3. Using scan tool, select LAST TEST FAIL. Record any other failed DTCs. If DTC P1153 or P1154 is also set, go to step  11. If DTC is not set, go to next step.
  4. Check exhaust system for leaks. If exhaust leak is found, repair as necessary and go to step  2. If no exhaust leak is found, go to next step.
  5. Visually inspect front HO2S for secure installation or corrosion on terminals. Check terminal tension at front HO2S and PCM. Check for damaged wiring. If a problem is found, repair as necessary. Retest system. If no problem is found, go to next step.
  6. Disconnect front HO2S connector. Connect a DVOM to PCM side of connectors high signal and ground, and low signal and ground. Turn ignition on and read DVOM at each connection. If reading is 3-4 mV, go to step  9. If voltage is not as specified, go to next step.
  7. Turn ignition off and check for damage to PCM pins or terminals. If a problem was found, repair as necessary and retest system. If no problem was found, go to next step.
  8. Inspect signal circuit for a short to voltage, ground or an open. If problem was found, repair as necessary. Retest system. If no problem was found, go to next step.
  9. With ignition off, disconnect PCM connector. Disconnect HO2S and check for high and low signal circuits between PCM and HO2S for shorting together. If a problem was found, repair as necessary. Retest system. If no problem was found, go to next step.
  10. Connect PCM and disconnect front HO2S. Using scan tool, check voltage. If reading is .43-.47 volts, go to next step. If voltage is not as specified, go to step  12.
  11. Check for fuel contamination, use of improper RTV sealant or excessive engine oil and coolant consumption. If no problems are found, replace affected HO2S. Retest system.
  12. Replace and reprogram PCM using required equipment. See PROGRAMMING . Retest system.
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