DTC P0136 (RO2_V): Rear O2S Circuit Malfunction
- Connect scan tool. Check for DTCs. If DTC P0130 also exists, go to next step. If DTC P0136 is only code set, go to step 3).
- Perform step 1) of DTC P0130 diagnosis. If P0130 failed because of problem in fuel system, repair fuel system as necessary. Clear DTCs and retest. Further inspection of P0136 is not necessary. If the failure is not in fuel system, go to next step.
- Warm engine to normal operating temperature, greater than 160°F (70°C). Operate engine at 2000-3000 RPM for 2 minutes. Observe rear O2S output signal. If indicated value fluctuates, check for poor O2S installation, exhaust system leaks ahead of rear O2S or loose O2S. Repair as needed. If no problems were found, replace rear O2S. If indicated value does not fluctuate, go to next step.
- If value is not fixed between 0.2 and 0.4 volt, replace rear O2S. If value is fixed between 0.2 and 0.4 volt, turn ignition off. Disconnect rear O2S connector and go to next step.
- Turn ignition on. Using a voltmeter connected to ground, measure voltage between ground and rear O2S connector terminal No. 4 (Black wire). If voltage reading is more than 0.2 volt, replace rear O2S. If voltage reading is 0.2 volt or less, check for an open in wiring between PCM and rear O2S connector or poor terminal contact at PCM and rear O2S connectors.