LEMON Manuals: Even more car manuals for everyone
Home >> BMW >> 2001 >> M3 2D Convertible >> Repair and Diagnosis >> Engine Performance >> System >> Engine Performance - Overview >> Engine Management Systems >> Siemens Ms 43.0 Engine Control System >> DM-TL (Diagnosis Module - Tank Leakage) >> Leak Diagnosis Test >> Phase 1 - Reference Measurement

Phase 1 - Reference Measurement

The ECM activates the pump motor. The pump pulls air from the filtered air inlet and passes it through a precise 0.5mm reference orifice in the pump assembly.

The ECM simultaneously monitors the pump motor current flow. The motor current raises quickly and levels off (stabilizes) due to the orifice restriction. The ECM stores the stabilized amperage value in memory. The stored amperage value is the electrical equivalent of a 0.5 mm (0.020") leak.

Fig 1: Leak Diagnosis Test Phase 1 - Reference Measurement
G03396020Courtesy of BMW OF NORTH AMERICA, INC.
scientia non olet · About LEMON Manuals