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Home >> Pontiac >> 2001 >> Aztek Base, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 88 (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 2002 GMC Sonoma and 2002 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.
    NOTE: If any other DTCs are set, diagnose affected DTCs before proceeding with this test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .
  2. Ensure engine is at operating temperature. Operate engine at greater than 1200 RPM for 2 minutes. Using scan tool, observe O2S 1 voltage. If O2S 1 voltage reading is greater than 400-500 millivolts, go to next step. If O2S 1 voltage reading is not greater than 400-500 millivolts, go to step  4.
  3. Operate vehicle within FAILURE RECORDS conditions. If DTC resets, go to next step. If DTC does not reset, see DIAGNOSTIC AIDS .
  4. Turn ignition off. Check for exhaust leak or improperly installed O2S 1. Check for damaged wiring. Repair as necessary. 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 1. Turn ignition on, with engine off. With a Digital Multimeter (DMM) measure the voltage on the PCM side of the O2S 1 high signal circuit to ground. Does the O2S 1 signal voltage measure about 450 millivolts? If yes, go to next step. If no, go to step  8.
  6. Install a jumper wire between the high signal circuit and the low signal circuit at the connector. With a scan tool, observe the O2S 1 voltage. Does the O2S 1 signal voltage measure about 0 millivolts? If yes, go to step  9. If no, go to next step.
  7. Test the low signal circuit for open, high resistance or short to voltage. If a condition is found, repair as necessary. 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 open, high resistance or short to voltage. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step  13. If no, go to step  11.
  9. Inspect for poor connections at the O2S 1. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step  13. If no, go to next step.
    NOTE: Determine cause of contamination before replacing O2S.
  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. After repairs, go to step  13. If connections are okay, go to next step.
  12. Replace PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  13. Use the 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.
  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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