Fuel System > Engine Control System>P0022 'A' Camshaft Position-Timing Over-Retarded (Bank 2)

Component Location

General Description

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. The PCM 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.

DTC Description

PCM monitors CAM phaser error while CMP signal is normally generating and vehicle is driving in 2000 ~ 3000rpm .If the CAM phaser does not move although PCM commands OCV duty cycle PCM determines that a faultexists and a DTC is stored.

DTC Detecting Condition

Item

Detecting Condition

Possible cause

DTC Strategy

•	Determines if the phaser is stuck or has steady-state error

•	Engine Oil

•

OCV stuck

•	CVVT stuck

Enable Conditions

•	CAM signal is normally generating

•	Vehicle is on driving (2000 ~ 3000RPM) for 5 minutes

Thresh
old value

Case 1

•	5 CAD < Cam Actual Position < 50 CAD

•	Duty Cycle > 90% or Duty Cycle <10%

Case 2

•	Cam Position error > 15 CAD (Difference between Actual Postion and Desired Position is more than 15°)

•	Timing Counter > 80

Diagnosis Time

•	Continuous (within 5min.)

MIL On Condition

•	2 Driving Cycles

Schematic Diagram

Signal Waveform And Data

This example shows a typical Crankshaft Position Sensor (CKPS) and Camshaft Position Sensor (CMPS) waveform at idle. If the 17th signal of the CKPS after missing tooth is aligned with the high signal of the CMPS at idle, PCM recognizes that Synchronization between CKPS and CMPS is completed.

Monitor DTC Status

Check DTC Status

(1)	Connect scantool to Data Link Connector(DLC).

(2)

IG "ON".

(3)	Select "DTC" button, and then Press "DTC Status" to check DTC'sinformation from the DTCs menu.

(4)	Read "DTC Status" parameter.

(5)

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 condition then, go to " System Inspection" procedure.

System Inspection

■ Visual Inspection

1.	Check oil level is O.K.

2.	Check for contamination of engine oil and OCV.

Has a problem been found?

	▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
	▶ Go to "Component Inspection" procedure.

Component Inspection

■ Check OCV resistance

1.	IG "OFF" and disconnect OCV connector.

Measure resistance between power and signal terminals of OCV. (Component Side)

Specification : 6.7 ~ 7.7 Ω

Is the measured resistance within specification ?

	▶ Go to "Check CAM PHASER with actuation test" as follows.
	▶ 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

1.	Connect scantool and IG "ON".

2.	Select "CAM PHASER INTAKE BANK 2" on the Actuation Test.

3.	Select "OIL CONTROL VALVE" on the Actuation Test.

4.	Activates "CAM PHASER INTAKE BANK 2" by pressing "STRT(F1)" key.

5.	Activates "OIL CONTROL VALVE" by pressing "STRT(F1)" key.

6.	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.

Verification Of Vehicle Repair

After a repair, it is essential to verify that the fault has been corrected.

1.	Connect scantool and select "DTC" button.

2.	Press "DTC Status" button and confirm that "DTC Readiness Flag" indicates "Completed". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions

3.	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.