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DTC P0133 - Ho2S No. 1 Bank 1/Slow Response

NOTE: ALWAYS inspect a faulty HO2S for contamination and correct cause before installing a new HO2S.
NOTE: If any DTCs are set (except for P0153, P1133, P1134, P1153 and/or P1154), diagnose them first.
  1. Perform On-Board Diagnostic (OBD) System Check. See BASIC TESTING article. Go to next step.
  2. Start engine and allow it to reach operating temperature. Operate vehicle within conditions required to set DTC. Using scan tool, observe SPECIFIC DTC parameter. If scan tool displays DTC P0133 FAILED THIS IGN, go to next step. If scan tool does not display DTC P0133 FAILED THIS IGN, check for an intermittent problem. See TESTS W/O CODES article.
  3. If scan tool also displays DTC P0153, P1133, P1134, P1153 and/or P1154 FAILED THIS IGN, replace affected HO2S. Retest system. If scan tool does not display these DTCs, go to next step.
  4. Visually inspect exhaust system for leaks near HO2S No. 1, bank 1. If leaks are found, repair as necessary and return to step 2). If no leaks are found, go to next step.
  5. Visually inspect HO2S No. 1, bank 1 for proper installation. Check for corrosion on terminals. Check terminal tension at HO2S No. 1, bank 1 and PCM. Repair as necessary. If no problem is found, go to next step.
  6. Disconnect HO2S No. 1, bank 1 harness connector. Using a voltmeter, measure voltage between high signal circuit and ground, then low signal circuit and ground. If reading is 3-4 volts, go to next step. If reading is not as specified, go to step 8).
  7. Using a fused jumper wire, connect high and low signal circuits of HO2S No. 1, bank 1 harness connector (PCM side) to ground. Turn ignition on. Using scan tool, monitor voltage. If reading is less than 10 mV and immediately returns to about 450 mV when jumper wire is removed, replace HO2S No. 1, bank 1. If reading is not as specified, replace PCM. Retest system.
  8. Inspect PCM connections and terminals for damage. Repair as necessary. Retest system. If PCM connections and terminals are okay, go to next step.
  9. Repair open, short or grounded HO2S No. 1, bank 1 high or low signal circuits. Retest system.
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