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 timing misalignment while no active faults is present and fully warmed up engine oil at idle.If the timing is misaligned PCM determines that a fault exists and a DTC is stored.
Item | Detecting Condition | Possible cause | |
DTC Strategy | ● Determines if CAM(B2) target is aligned correctly to crank | ● loosened CKPS ● Timing Misalignment | |
Enable Conditions | ● No active faults ● Fully warmed up at idle | ||
Thresh old value | Case 1 | ● 1 teeth misalignment at 80 ℃(176 ℉)＜ Oil Temperature ＜ 90 ℃(194℉) | |
Case 2 | ● 2 tooth misalignment at Lower than 80 ℃(176 ℉) or Higher than 90 ℃(194℉) | ||
Diagnosis Time | ● Continuous (Within 1min.) | ||
MIL On Condition | ● 2 driving Cycles | ||
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 "System 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.
Visual Inspection
Check oil level is O.K.
Check Oil and OCV is contaminated
Has a problem been found ?
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
▶ Go to "Visually check CKPS and target wheel" as follow
Visually check CKPS and target wheel
IG "OFF
Visually check CKPS is loosened or target wheel is deformed or damaged.
Is the above items normal ?
▶ Go to " Check CAM PHASER with actuation test" as follows
▶ Repair or replace as necessary and then 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 "Component Inspection" procedure.
CMPS, CKPS Inspection
IG "OFF" and connect scantool.
ENG "ON" and Measure signal waveform at terminal 3 of CMPS.
Measure signal waveform at terminal 1 or 2 of CKPS.
Is the measured signal waveform O.K ?
▶ Fault is intermittent. Drive the vehicle to meet the enable condition for the DTC. and go to "Verification of Vehicle Repair" procedure.
▶ Go to "Timing Mark Inspection" procedure as follow.
Timing Mark Inspection.
IG "OFF" and check the timing mark is correctly aligned.
Is the timing mark correctly aligned ?
▶ Fault is intermittent. Drive the vehicle to meet the enable condition for the DTC. and go to "Verification of Vehicle Repair" procedure.
▶ Repair or replace as necessary and then, 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.
