DTC P2270: Secondary HO2S (Sensor 2) Circuit Signal Stuck Lean ('05-08 models); DTC P2271: Secondary HO2S (Sensor 2) Circuit Signal Stuck Rich ('05-08 models)
- Turn the ignition switch ON (II).
- Clear the DTC with the HDS.
- Start the engine, and let it idle without load (in Park or neutral) until the radiator fan comes on.
- Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR) ('05 model), Engine coolant temperature (ECT SENSOR 1) ('06-08 models) above 158°F (70°C)
- Vehicle speed above 35 mph (56 km/h)
- Drive 25 seconds or more
- Monitor the OBD STATUS for DTC P2270 or P2271 in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES -Go to step 6.
NO -If the screen indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to step 3 and recheck.
- Turn the ignition switch OFF.
- Replace the secondary HO2S (Sensor 2) (see A/F SENSOR REPLACEMENT ).
- Turn the ignition switch ON (II).
- Reset the ECM/PCM with the HDS.
- Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
- Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
- Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR) ('05 model), Engine coolant temperature (ECT SENSOR 1) ('06-08 models) above 158°F (70°C)
- Vehicle speed above 35 mph (56 km/h)
- Drive 25 seconds or more
- Check for Temporary DTCs or DTCs with the HDS.
Is DTC P2270 or P2271 indicated?
YES -Check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM, then go to step 1.
NO -Go to step 14.
- Monitor the OBD STATUS for DTC P2270 or P2271 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -Troubleshooting is complete. If any other Temporary DTCs or DTCs were indicated in step 13, go to the INDICATED DTCS TROUBLESHOOTING .
NO -If the screen indicates FAILED, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM, then go to step 1. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to step 11.