1.4.3.1 Monitoring Function - Pump Current Diagnosis

P1434, P1447, P1448, P1449 

During the reference measurement phase, the current of the DMTL is monitored. When the current consumption does not reach 15 mA, a defective pump/motor is detected, and P1448 is stored. When the measured current consumption exceeds 40 mA, a defective pump/motor is also detected, and P1449 is stored.

The electrical solenoid is switched and the venting system is tight after the reference measurement. The solenoid is monitored by comparing the reference current and the idle current immediately after the solenoid has switched.

If the difference of < 2 mA between the two currents (reference current - idle current) is not reached, the DTC P1447 is stored.

The P1434 fault code is set when current fluctuations (caused by humidity in the DMTL) of > 1 mA are detected.