Diagnostic trouble code (DTC) information

Condition

Fig 1: Identifying Leak Diagnostic Pump

Courtesy of VOLVO CARS OF NORTH AMERICA.

If no fault is detected in the leak diagnostic unit, the control module runs a leak diagnostic of the fuel tank system. Diagnostic trouble code (DTC) ECM-400C is stored if the engine control module (ECM) detects a leak of 0.5-1.0 mm (minor leak) or a leak that is >1.0 mm (major leak). For more information about the leak diagnostics, see Leak diagnostics (certain markets only) .

Substitute Value

None.

Possible Source

Major leak:

Fuel tank filler cap missing or not tightened
Leakage that is 1 mm or greater in the fuel tank, fuel filler pipe, fuel tank filler cap, EVAP canister, canister purge (CP) valve, or in the hoses between these components
The fuel gauge does not function (This fault is detected by the rear electrical module).

Minor leak:

Leakage that is 0.5-1.0 mm or smaller in the fuel tank, fuel filler pipe, fuel tank filler cap, EVAP canister, canister purge (CP) valve, or in the hoses between these components
The fuel gauge does not function (This fault is detected by the rear electrical module).

Fault symptom[s]

Malfunction indicator lamp (MIL) lit.