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 increase engine power generation.
The electronic VGT adapted on R engine is activated by VGT actuator control unit and electronic actuator integrated with DC motor. Engine speed, APS signal, MAFS and Boost pressure sensor data are inputted to ECM. ECM controls VGT actuator control unit to control exhaust gas line as controlling VGT actuator duty to maintain optimum state of air compression. VGT actuator control unit controls DC motor with those signal so that exhaust gas can pass through the vane more or less cross sectional with operating spear gear?outter crank? inner crank?main link? unison ring?inner vane in order.
VGT actuator control unit judges that actuator is faulty by feed back signal of actuator position from turbo charger position sensor. If it is detected, VGT actuator control unit notifies faulty to ECM. The electronic actuator is much faster in operating response and stable in control than vacuum type.
In case of replacing VGT, perform the "COMPONENT CHANGE ROUTINE" procedure with scan tool. If the "COMPONENT CHANGE ROUTINE" procedure has not completed until automatic learning completed, it may cause vehicle performance and exhaust gas problem.
DTC P2263 is set when the difference of VGT operation target value and actual value is more than limited value more than 0.6 sec.
Item
Detecting Condition
Possible Cause
DTC Strategy
Signal Monitoring
VGT actuator
Turbo charger
Enable Conditions
Engine running
Threshold Value
Bad follow target value
Overload
Fault regarding learning.
Diagnostic Time
600 ms
Fail Safe
Fuel cut
NO
-
EGR Off
YES
Fuel Limit
Check
Lamp
ON
Fig.1) VGT actuator duty : 8% (-)duty(304Hz ±3%), 92% (+)duty.
Fig.2) VGT actuator duty at 3200 rpm : 73% (-)duty(304Hz ±3%)