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Home >> Oldsmobile >> 2002 >> Bravada AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 249 (Engine Controls Self-Diagnostics - 2.2L) >> Diagnostic Tests >> DTC P0133: O2S Circuit - Slow Response (Sensor 1) >> Diagnostic Procedures
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Diagnostic Procedures

WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
    2. NOTE: If any other DTCs are set, except HO2S DTCs, diagnose affected DTCs first before proceeding with this test. Refer to DIAGNOSTIC TROUBLE CODE DEFINITIONS  .
  2. Ensure engine is at normal operating temperature. Operate engine at greater than 1200 RPM for 2 minutes. Using scan tool, observe O2S 1 voltage. Does the scan tool indicate O2 voltage varying outside the specified value of 400-500 mV? If yes, go to next step. If no, go to step  4 .
  3. Operate vehicle within Failure Records conditions. Does the scan tool indicate this DTC failed this ignition? If yes, go to next step. If no, see DIAGNOSTIC AIDS  .
  4. Check for exhaust leak or improperly installed O2S 1. Check for damaged wiring. Did you find and correct the condition? If yes, go to step  13 . If no, go to next step.
  5. Turn ignition off. Disconnect the O2S. Turn ignition on. Measure the voltage on the O2S high signal circuit, PCM side, using a Digital Volt-Ohmmeter (DVOM) that is connected to a good ground. Does the voltage measure about 450 mV? If yes, go to next step. If no, go to step  8 .
  6. Jumper the high signal circuit to the low signal circuit, PCM side. With a scan tool, observe O2S voltage parameter. Does the scan tool indicate O2S voltage at or about 0 mV? If yes, go to step  9 . If no, go to next step.
  7. Test the low signal circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step  13 . If no, go to step  11 .
  8. Test the high signal circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step  13 . If no, go to step  11 .
  9. Test for poor connections at the O2S. Did you find and correct the condition? If yes, go to step  13 . If no, go to next step.
    NOTE: Determine the cause of contamination before replacing the sensor.
  10. Check for fuel contamination or improper use of RTV sealant. Repair as necessary. Replace O2S 1. After replacing sensor, go to step  13 .
  11. Check for poor connections at PCM. Repair as necessary. Did you find and correct the condition? If yes, go to step  13 . If no, go to next step.
  12. Replace PCM. See appropriate REMOVAL & INSTALLATION article. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  13. Turn ignition on, with engine off. Using scan tool, clear DTCs. Start engine and allow it to idle. Ensure engine is at normal operating temperature. Operate the vehicle within the Conditions for Running the DTC. See CONDITIONS FOR RUNNING DTC  . Does the DTC run and pass? If yes, go to next step. If no, go to step  2 .
  14. With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS  . If no, system is okay.
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