VGT(Variable Geometric 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 contrFolling VGT Control solenoid valve duty to maintain optimum state of air compression.
P0047 is set when "0"A is detected in VGT Control solenoid valve control circuit for more than 1 sec.. This code is due to open or short to ground in VGT Control solenoid valve circuit, or open in VGT Control solenoid valve component.
Item
Detecting Condition
Possible Cause
DTC Strategy
Signal monitoring
VGT Control solenoid valve circuit
VGT Control solenoid valve component
Enable Conditions
IG KEY ON
Threshold Value
short to GND, wiring open
Diagnostic Time
1000ms
Fail Safe
Fuel cut
NO
EGR Off
YES
Fuel Limit
MIL
VGT Control solenoid valve
component resistance
operating Hz
operating duty
14.7 ~ 16.1O (20?)
300Hz
79% at idle, decreases as accelerating
Fig.1) VGT Control solenoid valve output waveform at 79% duty. Duty decreases as boost pressure increases.
Fig.2) VGT Control solenoid valve duty decreased at acceleration.