P0077
DTC P0077 INTAKE VALVE CONTROL SOLENOID CIRCUIT HIGH (BANK 1)Component Location:
GENERAL DESCRIPTION
PCM controls OCV (0il Control Valve) with PWM (Pulse Width Modulator) signal to change oil passages supplying oil to CVVT that makes CAM position changes (advance or retard). OCV is integrated with oil filter and located on the engine block. The oil control valve is controlled by a pulse-width-modulated signal from the engine control unit. A duty cycle of zero commands the cam phaser to its default position. A duty cycle of 100 % commands the phaser to its maximum phased position. When the phaser must be controlled to an intermediate position, the duty cycle is maintained in the region of the 'hold position'. This is a medium duty cycle, usually between 35% and 65%, depending on temperature and voltage conditions. As the cam phaser is advanced and retarded, its position is measured using a toothed wheel. The wheel is attached to the camshaft, or to the cam phaser rotor. A sensor picks up the signal from the wheel and its output is read by the engine control unit. A cam signal is generated for each cam phaser on the engine. This requires a separate toothed wheel and cam sensor combination for each cam phaser. The cam signal and crankwheel signal are compared as the engine turns, and the phasing position is determined. The position is displayed in crank angle degrees, relative position from default. This position measurement is used as feedback for the position control software, which determines the required percent duty cycle commanded to the oil control valve.
DTC DESCRIPTION
When ECM/PCM detects short to power in OCV control circuit, ECM/PCM sets DTC P0077.
DTC Detecting Condition:
Specification:
Schematic Diagram (A/T):
Schematic Diagram (M/T):
Signal Waveform & Data:
MONITOR SCANTOOL DATA
1. Connect scantool to DLC (Data Link Cable).
2. Warm up the engine to normal operating temperature.
3. Monitor "OCV" parameter on scantool.
4. Is the "OCV" data displayed correctly?
YES - Fault is intermittent caused by poor contact in the sensor's and/or ECM/PCM's connector or was repaired and ECM/PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, ending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO - Go to "Terminal and Connector Inspection" procedure.
TERMINAL AND CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminal condition. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES - Repair as necessary and go to "Verification of vehicle Repair" procedure.
NO - Go to "Power Circuit Inspection" procedure.
CONTROL CIRCUIT INSPECTION
1. Check short to ground.
1. IG "OFF".
2. Disconnect OCV connector.
3. IG "ON" & ENG "OFF".
4. Measure voltage between terminal 1 of OCV harness connector and chassis ground.
Specification : Approx. 3.2 V
5) Is the measured voltage within specification?
YES - Go to "Component Inspection" procedure.
NO - Repair or replace as necessary and then, go to 'Verification of Vehicle Repair" procedure.
COMPONENT INSPECTION
1. Check OCV.
1. IG "OFF"
2. Disconnect OCV connector.
Specification:
3. Measure resistance between terminal 1 and 2 of OCV harness connector. (Component Side)
4. Is the measured resistance within specification?
YES
- Substitute with a known - good ECM/PCM and check for proper operation.
- If the problem is corrected, replace ECM/PCM and go to "Verification of Vehicle Repair" procedure.
NO
- 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.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes (DTCs)" mode.
2. Clear the DTCs and Operate the vehicle within DTC Enable conditions in General information.
3. Are any DTCs present?
YES - Go to the applicable troubleshooting procedure.
NO - System is performing to specification at this time.