Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information ECM-431D

Condition




The engine control module (ECM) monitors the power consumption of the pump for the leak diagnostic unit when the leak diagnostic is run.
The diagnostic trouble code (DTC) (signal too high or too low) is stored in the engine control module (ECM) if the power consumption of the pump is higher or lower than a particular value during the reference phase.
The diagnostic trouble code (DTC) (Faulty signal) is stored in the engine control module (ECM) if the power consumption for the pump fluctuates too much during the reference phase.
The power consumption of the pump must drop when the leak diagnostic pump valve moves from the reference check to pressurizing the fuel tank system. The diagnostic trouble code (DTC) (signal missing) is stored in the engine control module (ECM) if the value for the power consumption of the pump drops too quickly, slowly or not at all.
The diagnostic trouble code (DTC) can be diagnosed when leak diagnostics is run.
For further information about leak diagnostics, see VIDA Design and Function.

Substitute value
The leak diagnostic is disabled.

Possible source

Signal too high
- Contact resistance in the terminals
- Blocked filter in the leak diagnostic unit
- Blocked hose between the filter and the leak diagnostic unit
- Damaged leak diagnostic unit.

Signal too low
- Contact resistance in the terminals
- Damaged leak diagnostic unit.

Faulty signal
- Contact resistance in the terminals
- Damaged heater element
- Incorrect control of heater element
- Damaged leak diagnostic unit.

Signal missing
- Contact resistance in the terminals
- Blocked hose between the leak diagnostic unit and the EVAP canister
- Damaged leak diagnostic unit.

Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.