Mass air flow sensor: Diagnostics

Three different diagnostic trouble codes can be generated if the mass air flow sensor develops a fault:

• If the mass air flow sensor does not send a frequency at all to the control module, diagnostic trouble code P0100 will be generated. This can be due to a break in one of the leads.
• If the frequency is too low, diagnostic trouble code P0102 will be generated. This can be due to a major leak between the mass air flow sensor and the throttle body or and internal fault in the mass air flow sensor.
• If the frequency is too high, diagnostic trouble code P0103  will be generated. This can be due to and internal fault in the mass air flow sensor.