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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 P0134: O2S Circuit - Insufficient Activity (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. Ensure engine is at operating temperature. Operate engine at greater than 1500 RPM for 30 seconds. Using scan tool, observe O2S 1 voltage. If O2S 1 voltage reading is greater than 400-500 mV, go to next step. If O2S 1 voltage reading is not greater than 400-500 mV, go to step  4 .
  3. Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start engine. Operate vehicle within the Conditions for Running DTC. See CONDITIONS FOR RUNNING DTC  . You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition? If yes, go to next step. If no, problem is intermittent. Refer to INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 2.2L SONOMA & S10 PICKUP article.
  4. Turn ignition off. Disconnect O2S 1. Turn ignition on, with engine off. Observe O2S 1 voltage parameter with a scan tool. Is O2S 1 voltage parameter more than 800 mV? If yes, go to step  6 . If no, go to next step.
  5. Measure voltage from the high signal circuit of the O2S 1 harness connector on the engine harness side to a good ground with a DVOM. Is voltage more than 0.2 volt? If yes, go to step  7 . If no, go to step  8 .
    6. NOTE: The sensor may be damaged if circuit is shorted to a voltage source.
  6. Test the O2S 1 high signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  13 .
  7. Measure voltage from the low signal circuit of the O2S 1 harness connector on the engine harness side to a good ground with a DVOM. Is voltage more than 2 volts? If yes, go to step  11 . If no, go to step  9 .
  8. Test the O2S 1 high signal circuit for an open. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  13 .
  9. Connect a 3-amp fused jumper wire between the high signal circuit of the O2S 1 harness connector on the engine harness side and the low signal circuit of the O2S 1 harness connector on the engine harness side. Observe the O2S 1 voltage parameter with a scan tool. Is O2S 1 voltage parameter less than 100 mV? If yes, go to step  12 . If no, go to next step.
  10. Test the O2S 1 low signal circuit for an open. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  13 .
  11. Test the O2S 1 low signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  13 .
  12. Test for an intermittent and for a poor connection at the O2S 1. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  14 .
  13. Test for an intermittent and for a poor connection at the PCM. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  15 .
  14. Replace O2S 1. After replacing sensor, go to step  16 .
  15. Replace PCM. See appropriate REMOVAL & INSTALLATION article. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  16. Use scan tool in order to clear the DTCs. Turn ignition off for 30 seconds. Start engine. 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 .
  17. 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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