P2270

DTC P2270: Secondary HO2S (Sensor 2) Circuit Signal Stuck Lean

1. Turn the ignition switch ON (II).
2. Reset the ECM with the HDS.
3. 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.
4. Test-drive under these conditions:

- Engine coolant temperature above 176 °F (80 °C)
- Vehicle speed between 35 mph (56 km/h) or more
- Drive 1 minute or more

5. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2270 or P2271 indicated?

YES - Replace the secondary HO2S (Sensor 2).

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM.