What does code P1202 mean?

Q: What does code P1202 mean?

Alternative Fuel Gas Mass Sensor Circuit Low Frequency. P1202 on a GM vehicle means the powertrain control module (PCM) has detected that the signal frequency from the alternative fuel gas mass sensor is lower than the expected range for the current operating conditions. This sensor measures the mass flow of gaseous fuel, such as compressed natural gas (CNG) or liquefied petroleum gas (LPG), and the PCM uses its frequency output to calculate fuel delivery; a low-frequency signal indicates a fault in the sensor circuit or the sensor itself.

DTC codes / GM codes / P1202

P1202 · GMAlternative Fuel Gas Mass Sensor Circuit Low Frequency

P1202 on a GM vehicle means the powertrain control module (PCM) has detected that the signal frequency from the alternative fuel gas mass sensor is lower than the expected range for the current operating conditions. This sensor measures the mass flow of gaseous fuel, such as compressed natural gas (CNG) or liquefied petroleum gas (LPG), and the PCM uses its frequency output to calculate fuel delivery; a low-frequency signal indicates a fault in the sensor circuit or the sensor itself.

SystemPowertrain

Code typeGM specific

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Guidance is general and written for GM vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.