LEMON Manuals: Even more car manuals for everyone
Home >> Subaru >> 2001 >> Outback Base, Standard >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Controls - Self-Diagnostics - 2.2L & 2.5L >> Diagnostic Tests >> DTC P0136: Rear Ho2S Circuit Malfunction

DTC P0136: Rear Ho2S Circuit Malfunction

  1. Perform basic diagnostic procedure. See BASIC DIAGNOSTIC PROCEDURE . If DTC P1130 and/or P1131 also exist for Forester, Impreza, Legacy and Outback 2.5L M/T and Outback Sport, go to next step. If DTC P0131 and/or P0132 also exist for Legacy and Outback 2.5L A/T, go to next step. If DTC P0136 is only DTC set for all models, go to step  3.
  2. Perform appropriate DTC P0131, P0132, P1130 or P1131 diagnostic routine. If DTC P0131, P0132, P1130 or P1131 failed because of problem in fuel system, repair fuel system as necessary. Further inspection of DTC P0136 is not necessary. If the failure is not in fuel system, go to next step.
  3. Start engine and warm to operating temperature above 160°F (70°C). Operate engine at 2000-3000 RPM for 2 minutes. Using scan tool, observe rear HO2S signal. If indicated value fluctuates, go to step  7. If indicated value does not fluctuate, go to next step.
  4. If rear HO2S signal is fixed between 0.2 and 0.4 volt, go to next step. If rear HO2S signal is not fixed between 0.2 and 0.4 volt, replace rear HO2S.
  5. Turn ignition off. Disconnect ECM connector B136 (30-pin connector) and rear HO2S connector. Using an ohmmeter, measure resistance between ECM connector B136 (30-pin connector) terminal No. 16 and rear HO2S connector terminal No. 3. See Figure and Figure . If resistance is more than 3 ohms, locate and repair open circuit in wiring between ECM and rear HO2S. See WIRING DIAGRAMS article. If resistance is not more than 3 ohms, go to next step.
  6. Turn ignition off. Reconnect ECM connector B136 (30-pin connector) and leave rear HO2S connector disconnected. Turn ignition on. Using a DVOM connected to ground, measure voltage at rear HO2S connector terminal No. 4. If voltage is more than 0.2 volt, replace rear HO2S. If voltage is not more than 0.2 volt, locate and repair open circuit in wiring and check for poor terminal contact in connectors between ECM and rear HO2S. See WIRING DIAGRAMS article.
  7. Check for poor or loose HO2S installation, exhaust system leaks, holes and loose components ahead of rear HO2S. Repair as needed. If no problems were found, replace rear HO2S. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES  and VERIFICATION PROCEDURE  .
scientia non olet · About LEMON Manuals