The CVVT (Continuously Variable Valve Timing) system is installed to the chain sprocket of the intake camshaft. This system controls the intake camshaft to provide the optimal valve timing for every driving condition. The ECM controls the Oil Control Valve(OCV), based on the signals output from mass air flow, throttle position and engine coolant temperature. The CVVT controller regulates the intake camshaft angle using oil pressure through the OCV. As result, the relative position between the camshaft and the crankshaft becomes optimal, and the engine torque improves, fuel economy improves, exhaust emissions decrease under overall driving conditions.
PCM monitors OCV stuck while cam sinal is normally generating and Valve cleaning is not in progress .If the CAM Acutal Position is too high or low and Difference between Cam Actual Positionand Desire Position is higher than 20° PCM determines that a fault exists and a DTC is stored.
Item | Detecting Condition | Possible cause | |
DTC Strategy | ● Determines if oil control valve is stuck | ● Oil PressureLoss ● OCV seizure | |
Enable Conditions | ● Valve cleaning not in progress ● CAM signal is normally generating | ||
Thresh old value | Case 1 | ● Cam Actual Position > 50 CAD or Difference between CAM Actual Position and DesirePosition > 20 CAD | |
Case 2 | ● Cam Actual Position < 5 CAD orDifference between CAM Actual Position and DesirePosition > 20 CAD | ||
Diagnosis Time | ● Continuous (Within 1min.) | ||
MIL On Condition | ● 2 driving Cycle |
Resistance (Ω) | 6.7 ~ 7.7 |
Check DTC Status
Connect scantool to Data Link Connector(DLC).
IG "ON".
Select "Diagnostic Trouble Codes(DTCs)" mode, and then Press F4(DTAL) to check DTC's information from the DTCs menu
Read "DTC Status" parameter.
Is parameter displayed "Present fault"?
▶ Go to "Terminal and Connector inspection" procedure.
▶ Fault is intermittent caused by PCM memory was not cleared after repair. Erase DTC and drive the vehicle to satisfy the enable codition then,go to " System Inspection" procedure.
Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
Has a problem been found?
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure
▶ Go to " Power Circuit Inspection " as follow
IG "OFF" and disconnect OCV connector.
IG "ON" & ENG "OFF".
Measure voltage between terminal 2 of OCV harness connector and chassis ground.
Be careful not to change the connectors for B1 and B2)
Specification : B+
Is the measured voltage within specification ?
▶ Go to " Control Circuit Inspection " procedure.
▶ Check that Fuse between Main Relay and OCV is open.
▶ Check open between main relay and OCV.
▶ Check short to ground between Main Relay and OCV.
▶ Repair or replace as necessay go to "Verification of Vehicle Repair " procedure.
IG "OFF" and disconnect OCV connector.
IG "ON" & ENG "OFF".
Measure voltage between terminal 1 of OCV harness connector and chassis ground.
Specification : Approx. below 1V
Is the measured voltage within specification ?
▶ Go to "System Inspection" procedure.
▶ Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
Visual Inspection
Check oil level is O.K.
Check oil is contaminated.
Check that any oil leakage is occurred around CVVT system.
Has a problem been found ?
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
▶ Go to "Component Inspection" procedure
OCV Inspection
IG "OFF" & Disconnect OCV connector.
Measure resistance between terminal 1 and 2 of OCV connector (Component Side)
Resistance (Ω) | 6.7 ~ 7.7 |
Is the measured resistance within specification ?
▶ Go to "Check CAM PHASER with actuation test" as follow.
▶ Substitute with a known - good OCV and check for proper operation.
▶If the problem is corrected, replace OCV and go to "Verification of Vehicle Repair" procedure.
Check CAM PHASER with actuation test
connect scantool and IG "ON"
Select "CAM PHASER INTAKE BANK 1" on the Actuation Test
Select "OIL CONTROL VALVE" on the Actuation Test
Activates "CAM PHASER INTAKE BANK 1" by pressing "STRT(F1)" key
Activates "OIL CONTROL VALVE" by pressing "STRT(F1)" key
Repeat this procedure 4 or 5 times to ensure CAM PHASER and intake valve control solenoid reliability
Has a problem been found ?
▶ Substitute with a known - good CVVT or OCV and check for proper operation.
▶ If the problem is corrected, replace CVVT or OCV and go to "Verification of Vehicle Repair" procedure.
▶ Fault is intermittent. Drive the vehicle to meet the enable condition for the DTC. and Go to "Verification of Vehicle Repair" procedure.
After a repair, it is essential to verify that the fault has been corrected.
Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode
Press F4(DTAL) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions
Read "DTC Status" parameter
Is parameter displayed "History(Not Present) fault"?
▶ System performing to specification at this time. Clear the DTC
▶ Go to the applicable troubleshooting procedure.