Diagnostic trouble code (DTC) information
Condition
Diagnostic trouble code (DTC) ECM-431D (signal too high or too low) is stored if the power consumption of the pump in the leak diagnostic unit is higher or lower than a particular value during the reference phase.
Diagnostic trouble code (DTC) ECM-431D (faulty signal) is stored if the power consumption for the pump in the leak diagnostic unit 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. Diagnostic trouble code (DTC) ECM-431D (signal missing) is stored if the value for the power consumption of the pump drops too quickly, slowly or not at all.
The diagnosis is carried out when the ignition is switched off.
For more information about the leak diagnostics, see Leak diagnostics (certain markets only) .
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
- Defective leak diagnostic unit.
Signal too low:
- Contact resistance in the terminals
- Defective leak diagnostic unit.
Faulty signal:
- Contact resistance in the terminals
- Defective leak diagnostic unit
- Defective control of the heater element (This fault is detected by the central electronic module).
Signal missing:
- Contact resistance in the terminals
- Blocked hose between the leak diagnostic pump and the EVAP canister
- Defective leak diagnostic unit.
Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.