P0102

DTC P0102 Mass Air Flow (MAF) Sensor Circuit Low Voltage

Circuit Description

The mass air flow (MAF) sensor is an air flow meter that measures the amount of air that enters the engine. It is fitted between the air cleaner and turbocharger. A small quantity of air that enters the engine indicates deceleration or idle speed. A large quantity of air that enters the engine indicates acceleration or a high load condition. The sensor has the following circuits.

^ Ignition voltage circuit
^ Low reference circuit
^ MAF sensor signal circuit

The ECM monitors the MAF sensor signal voltage. This output voltage will display on the scan tool as a voltage parameter and as a grams per second (g/s) parameter. If the ECM detects an excessively low signal voltage this DTC will set.

Condition for Running the DTC

^ DTC P0103 is not set.
^ The battery voltage is more than 10 volts.
^ The ignition switch is ON.
^ The engine runtime is longer than 30 seconds.

Condition for Setting the DTC

^ The ECM detects that the MAF sensor signal voltage is less than 0.08 volts for 6 seconds.

Action Taken When the DTC Sets

^ The ECM illuminates the MIL when the diagnostic runs and fails. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type A.
^ The ECM uses a MAF substitution of default value.
^ The ECM limits fuel injection quantity.
^ The ECM inhibits EGR control.
^ The ECM inhibits DPF regeneration control.
^ The ECM inhibits cruise control.

Condition for Clearing the DTC

^ Refer to DTC Type Definitions for Condition for Clearing the MIL/DTC - Type A.

Diagnostic Aids

^ If an intermittent condition is suspected refer to Intermittent Conditions in this section.

Test Description

The number below refers to the step number on the Circuit System Testing.

4. This step testes for proper operation of the circuit in the signal circuit. If the fuse in the jumper opens when your perform this test the signal circuit is shorted to ground or low reference circuits.

Circuit/System Testing DTC P0102