DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Special Tools
EN-46999 Displacement On Demand Tester
For equivalent regional tools, refer to Special Tools (See: Powertrain Management/Computers and Control Systems/Tools and Equipment).
Circuit/System Verification
Note: The engine oil level and the oil pressure are critical to the correct operation of the Cylinder Deactivation System. Verify that the
engine has the correct oil level and the correct oil pressure before continuing with this diagnostic. Refer to Oil Pressure Diagnosis and
Testing (See: Engine, Cooling and Exhaust/Engine/Testing and Inspection/Component Tests and General Diagnostics/Oil Pressure
Diagnosis and Testing). Inspect the Valve Lifter Oil Filter for a restriction or blockage. Refer to Valve Lifter Oil Filter Replacement (See:
Engine, Cooling and Exhaust/Engine/Camshaft, Lifters and Push Rods/Lifter / Lash Adjuster/Service and Repair/Valve Lifter Oil Filter
Replacement).
1. Ignition ON, observe the scan tool DTC information. Verify that DTC P0201-P0208, P0351-P0358, P3401, P3425, P3441, or P3449 is not
set.
锟斤拷If a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble
Code (DTC) List - Vehicle) for further diagnosis.
2. Engine idling at the normal operating temperature. Verify there is no abnormal engine noise.
锟斤拷If there is an abnormal engine noise, refer to Symptoms - Engine Mechanical (See: Engine, Cooling and Exhaust/Engine/Testing and
Inspection/Symptom Related Diagnostic Procedures/Symptoms - Engine Mechanical) for further diagnosis.
3. Perform the Cylinder Deactivation (Active Fuel Management) System Compression Test (See: Engine, Cooling and Exhaust/Engine/Testing
and Inspection/Component Tests and General Diagnostics/Cylinder Deactivation (Active Fuel Management) System Compression Test). The
Cylinder Deactivation System should pass the compression test.
4. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the
conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
1. Ignition OFF, remove the valve lifter oil manifold assembly ignition fuse from the underhood fuse block.
Note: Probe each terminal at the underhood fuse block with a test lamp connected to ground to determine what terminal to connect the
DMM. The test lamp should not illuminate on the circuit that needs to be tested.
2. Connect a DMM between the ignition circuit fuse terminal going to the valve lifter oil manifold assembly and the ECM housing.
3. Ignition ON, command each Cylinder 1, 4, 6, and 7 Deactivation solenoid ON and OFF with the scan tool. Verify the resistance of each
solenoid is between 11-18 ohm with the solenoid commanded ON.
锟斤拷If greater than the specified range for all cylinder deactivation solenoids, test the ignition circuit for an open/high resistance.
锟斤拷If greater than the specified range for one or more but not all cylinder deactivation solenoids, test both the control circuit and ignition
circuit for an open/high resistance or an open/high resistance in the cylinder deactivation solenoid. If the circuits and solenoid test normal
replace the ECM.
4. If all circuits and components test normal, refer to Cylinder Deactivation (Active Fuel Management) Valve Lifter Oil Manifold Diagnosis and
Testing (See: Engine, Cooling and Exhaust/Engine/Testing and Inspection/Component Tests and General Diagnostics/Cylinder Deactivation
(Active Fuel Management) Valve Lifter Oil Manifold Diagnosis and Testing) for further mechanical diagnosis of valve lifter oil manifold
assembly.
Component Testing
Static Test
1. Ignition OFF, disconnect the harness connector at the valve lifter oil manifold assembly.
2. Connect the harness that is labeled resistance from the displacement on demand (DOD) tester to the valve lifter oil manifold connector.
3. Connect the power leads from the DOD tester to B+ and ground. Test for 11-18 ohm on each valve lifter oil manifold solenoid.
锟斤拷If not within the specified range for each solenoid, replace the valve lifter oil manifold assembly.
