Throttle flap actuator controls throttle flap when turning engine OFF as loading or unloading vacuum from vacuum pump installed in alternator with ECM duty control.
Throttle flap valve cut off intake air when turning engine OFF to prevent Over-run( engine does not stop and runs for a while when turning OFF engine because of rotating inertia and fuel leakage in injector nozzle ) of diesel engine.
Checking operation of throttle flap valve is possible as checking that throttle flap valve operates once when turning engine OFF.
Item
Detecting Condition
Possible Cause
DTC Strategy
? Signal monitoring
? Throttle flap actuator circuit
? Throttle flap actuator component
Enable Conditions
? Ignition "ON"
Threshold Value
? Open or short in circuit
Diagnostic Time
? 480ms
Fail Safe
Fuel Cut
NO
EGR Off
YES
Fuel Limit
MIL