4.
Monitor "INLET THROTTLE ACTU." parameter on the Scantool.
Specification : 94.5% duty outputted except the operation of throttle flap
9.4% duty outputted at the operation of throttle flap
As closing or opening vacuum line from vacuum pump which is installed at the end of cam shaft, with the method of duty control, Throttle control Actuator controls throttle flap valve when engine is turning OFF.When turning engines OFF, Throttle flap valve cuts intake air to prevent overrun phenomena.(In spite of turning engine OFF, engine does not stop and runs for a while due to rotating inertia of engine and fuel leakage at injector nozzle. ) To check its operation, watch if it operate when turning engine OFF.
Throttle Control actuator(TCA) helps EEGR actuator in EGR control as controlling throttle flap position with the method of duty control. In EURO 3 diesel engine, precise EGR control is more difficult than in EURO 4 engine. Even though EGR actuator opens exhaust gas outlet fully, it is difficult for exhaust gas to be inhaled at intake manifold because intake air is already exist to be inhaled at there in EURO 3 engine. However in EURO 4 engine, controlling throttle flap position, it is possible to regulate the differential pressure between exhaust and intake air. With the control of the differential pressure, the amount of exhaust air to be recirculated is regulated. Besides, When turning engines OFF, Throttle control actuator cuts intake air to prevent dieselling.(In spite of turning engine OFF, engine does not stop and runs for a while due to rotating inertia of engine and fuel leakage at injector nozzle. )
P2112 is set when "0"A in throttle contor actuator is detected for more than 0.11 sec. this code is due to 1)open or short to ground in control circuit or 2)internal open in actuator component.
P2112 is set when "0"A in throttle flap actuator is detected for more than 1 sec. this code is due to 1)open or short to ground in control circuit or 2)internal open in actuator component.
Item | Detecting Condition | Possible Cause | ||
DTC Strategy | ● Voltage monitoring | ● Throttle control actuator circuit ● Throttle control actuator component | ||
Enable Conditions | ● IG KEY "ON" | |||
ThresholdValue | ● Short to GND, Wiring open | |||
DiagnosticTime | ● 110ms | |||
Fail Safe | Fuel Cut | NO | ||
EGR Off | YES | |||
Fuel Limit | NO | |||
MIL | NO | |||
Item | Detecting Condition | Possible Cause | ||
DTC Strategy | ● Voltage monitoring | ● TCA circuit ● TCA component | ||
Enable Conditions | ● IG KEY "ON" | |||
ThresholdValue | ● Short to battery ● Wiring open | |||
DiagnosticTime | ● 1 sec. | |||
Fail Safe | Fuel Cut | NO | ||
EGR Off | YES | |||
Fuel Limit | NO | |||
MIL | OFF | |||
Throttle control actuator component resistance | Throttle control actuator operating Hz | Throttle control actuator operating duty |
23.8~31.3Ω (20℃) | 300Hz | 38%(no vacuum)~90%(vacuum) |
Throttle control actuator fully opened | Throttle control actuator fully closed | Throttle control actuator operating Hz |
5% | 95% | 250±7.5 Hz |
Connect Scantool to Data Link Connector (DLC).
Warm engine up to normal operating temperature.
Turn "OFF" electrical devices and A/C.
Monitor "INLET THROTTLE ACTU." parameter on the Scantool.
Specification : 94.5% duty outputted except the operation of throttle flap
9.4% duty outputted at the operation of throttle flap
Electrical systems consist of a lot of harness and connectors, poor connection of terminals can cause various problems and damge of component.
Perform checking procedure as follows.
Check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.
Check connecting condition of ECM and component connector : Check terminal seperation, damage of locking device and connecting condition between terminal and wiring.
Disconnect the pin which requires checking at male connector and insert it to the terminal at female connector for checking connecting condition. ( after checking, reconnect the pin at correct position. )
Is the problem found?
▶ Repair the trouble causing part and go to "Verification of Vehicle Repair".
▶ Go to "Power Circuit Inspection".
Check power circuit voltage
IG KEY "OFF", ENGINE "OFF".
Disconnect Throttle control actuator.
IG KEY "ON".
Measure the voltage of Throttle control actuator connector terminal 2.
Specification : 11.5V~13.0V
Is the measured voltage within the specification?
▶ Go to "Control Circuit Inspection".
▶ Repair E/R JUNCTION BOX 15A INJ fuse and related circuit and go to "Verification of Vehicle Repair".
Check power circuit voltage
IG KEY "OFF", ENGINE "OFF".
Disconnect Throttle control actuator.
IG KEY "ON".
Measure the voltage of Throttle control actuator connector terminal 3.
Specification : 11.5V~13.0V
Is the measured voltage within the specification?
▶ Go to "Control Circuit Inspection".
▶ Repair E/R JUNCTION BOX 15A INJ fuse and related circuit and go to "Verification of Vehicle Repair".
Check monitoring voltage in control circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect Throttle control actuator connector.
IG KEY "ON".
Measure the voltage of Throttle control actuator connector terminal 1.
specification : 3.2V~3.7V
Is the measured voltage within the specification?
▶ Go to "Component Inspection".
▶ When voltage is not detected : Go to "2. Check open in control circuit" as follows.
▶ When high voltage is detected : Repair short to battery in control circuit and go to "Verification of Vehicle Repair".
Check open in control circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect Throttle control actuator connector and ECM connector.
Check continuity between throttle control actuator connector terminal 1 and ECM connector(CUD-K) terminal 90.
Specification : Continuity ( below 1.0Ω )
Is the measured resistance within the specification?
▶ Repair short to ground in control circuit and go to "Verification of Vehicle Repair".
▶ Repair open in control circuit and go to "Verification of Vehicle Repair".
Check monitoring voltage in control circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect Throttle control actuator connector.
IG KEY "ON".
Measure the voltage of Throttle control actuator connector terminal 2.
Specification : 0.0V~0.1V
Is the measured voltage within the specification?
▶ Go to "2.Check open in control circuit"as follows.
▶ Repair short to battery in control circuit and go to "Verification of Vehicle Repair".
Check open in control circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect Throttle control actuator connector and ECM connector.
Check continuity between throttle control actuator connector terminal 2 and ECM connector(CUD-K) terminal 90.
Specification : Continuity ( below 1.0Ω )
Is the measured resistance within the specification?
▶ Go to "3. Check short to ground in control circuit" as follows.
▶ Repair open in throttle control actuator control circuit and go to "Varification of Vehicle Repair".
Check short to ground in control circuit
IG KEY "OFF", ENGINE "OFF"
Disconnect Throttle control actuator connector.
Check continuity between throttle control actuator connector terminal 2 and chassis ground.
Is the measured resistance within the specification? (Is control circuit insulated with ground?)
▶ Go to "Ground Circuit Inspection".
▶ Repair short to ground in control circuit and go to "Verification of Vehicle Repair".
IG KEY "OFF", ENGINE "OFF"
Disconnect Throttle control actuator connector.
IG KEY "ON"
Measure the voltage of Throttle control actuator connector terminal 3. [ TEST "A" ]
Measure the voltage between Throttle control actuator connector terminal 3 and terminal 4. [ TEST "B" ]
( terminal 3 : Check + prove , terminal 4 : Check - prove )
Specification : [TEST "A"] Voltage - [TEST "B"] Voltage = below 200mV
Is the measured voltage within the specification?
▶ Go to "Component Inspection".
▶ When "B" voltage is not detected : Repair open in ground circuit and go to "Verification of Vehicle Repair".
▶ When the voltage difference between "A" and "B" is above 200mV : Eliminate the causes of excessive resistance and go to "Verification of Vehicle Repair".
Check Throttle control actuator component resistance
IG KEY "OFF", ENGINE "OFF".
Disconnect Throttle control actuator.
Check the resistance of Throttle control actuator.
Specification : 23.8~31.3Ω (20℃)
Is the measured resistance within the specification?
▶ Go to "Verification of Vehicle Repair".
▶ Replace Throttle control actuator and go to "Verification of Vehicle Repair".
Check Throttle control actuator component resistance
IG KEY "OFF", ENGINE "OFF"
Disconnect intake hose connected to throttle control actuator.
Check if throttle control actuator is contaminated with carbon fraction.
Check if throttle flap moves smoothly as touching it with hand (perform this process at IG KEY "OFF" state.)
※ Check if abnormal noise, valve shaft stuck, too much wear are detected.
Specification : Flap moves smoothly and carbon fraction, too much wear, abnormal noise are not detected.
Is throttle control actuator is OK after performing visual inspection?
▶ Go to "2. Throttle control actuator operating test" as follows.
▶ If same symptom is detected after clear carbon fraction up, replace throttle control actuator and go to "Verification of Vehicle Repair".
Throttle control actuator operating test
IG KEY "OFF", ENGINE "OFF"
Disconnect intake hose connected to throttle control actuator.
ENGINE "ON"
Check if throttle control actuator is in wide open state during engine running.
ENGINE "OFF"
Check if throttle flap is closed once and opened again at the point of turning engine OFF.
※ Check if abnormal noise or irregular moving of flap is detected.
Specification :
Throttle flap moves smoothly.
At engine ON : Throttle control actuator opened.
At the point of turning engine OFF : Throttle flap is closed once and opened again.
Is throttle flap moves smoothly?
▶ Go to "Verification of Vehicle Repair".
▶ Replace throttle control actuator and go to "Verification of Vehicle Repair".
After a repair, it is essential to verify that the fault is corrected.
After connecting Scantool select "DIAGNOSTIC TROUBLE CODES(DTCs)" mode.
Clear recorded DTC using Scantool.
Drive the vehicle within DTC "Enable conditions" in "General information".
After selecting "DIAGNOSTIC TROUBLE CODES(DTCs)" mode and check if DTC is recorded again.
Are any DTCs recorded ?
▶ Go to the DTC guide of recorded NO. in Scantool.
▶ System operates within specification.
