Circuit/System Verification
- Observe the DTC information with a scan tool. Verify that DTC P121B and P121C are not set.
- If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Ignition ON, engine speed between 1,375 and 1,425 RPM, normal operating temperature. Verify the scan tool MAF Sensor parameter is between 1,950 and 2,250 Hz.
- Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.