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.

P0048 is set when excessive current is detected in WGT Control solenoid valve control circuit for more than 1 sec.. This code is due to short to battery in control circuit or internal short of 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.