Diagnostic trouble code (DTC) information ECM-431A

Condition 

Fig 1: Identifying Leak Diagnostic Unit

Courtesy of VOLVO CARS OF NORTH AMERICA.

The engine control module (ECM) checks the function of the pump by measuring the current through the leak diagnostic pump.

If the engine control module (ECM) registers that the current curve is uneven, it interprets this as an incorrect reference leak in the pump. The diagnostic trouble code (DTC) is then stored.

The diagnostic trouble code (DTC) can be diagnosed when the leak diagnostic system is run.

Substitute Value 

• The leak diagnostic is cancelled.

Possible Source 

• Incorrect control of the heating element (fault detected in the central electronic module (CEM))
• Dirt or damp in the pump
• Damaged leak diagnostic pump.

Fault symptom[s] 

• Malfunction indicator lamp (MIL) lit.