WGT(Waste Gate Turbocharger) is the device which increases the efficiency of turbocharger at low rpm and lasts optimum turbo efficiency at high rpm as varying the cross sectional area through which exhaust gas passes turbocharger impeller. It relieves turbo lag at low speed and increse engine power genetation.

Engine speed, APS signal, MAFS and Boost pressure sensor information is inputted to ECM.

ECM actuates vacuum diafragm which controls exhaust gas line as controlling WGT Control solenoid valve duty to maintain optimum state of air compression.

P0046 is set when Boost error out of calibration range for 7.5 seconds or Boost error is 10bar and boost feed-back atmospheric pressure is 10bar for 7.5 seconds. This code is due to WGT Control solenoid valve component.

Fig.1) WGT Control solenoid valve output waveform at 79% duty. Duty decreases as boost pressure increases.

Fig.2) WGT Control solenoid valve duty decreased at acceleration.