Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

Condition
Engine control module (ECM) measures the amount of air that passes through the inlet manifold using a mass air flow sensor. The control module checks the direct voltage from the sensor.

Note! The mass air flow sensor and air temperature sensor are integrated in the same component.

The diagnostic trouble code (DTC) is stored if the control module detects that:
- The direct voltage is lower than 0.049 V.
- Incorrect value lasts longer than 9 seconds.
- Incorrect value lasts for 2 or more subsequent driving cycles.
The control module's test for the diagnostic trouble code (DTC) starts in the event of:
- Ignition switch position II.

Note! The control module can only detect the fault once the test has been started and the diagnostic trouble code (DTC) is stored when the conditions are met.





Substitute value
- A value calculated from engine speed (RPM) and pressure in the intake manifold is used.

Possible source
- Open-circuit in signal cable or ground lead.
- Contact resistance and oxidation in the terminals.
- Short-circuit to ground in the signal cable.
- Damaged mass air flow (MAF) sensor.

Fault symptom[s]
- Malfunction indicator light (MIL), on