Diagnostic Instructions
DTC Descriptor
DTC P3400: Cylinder Deactivation System Performance
Circuit/System Description
The Cylinder Deactivation System Performance diagnostic is a test of the internal mechanical condition of the engine, during operation in V3 mode. The engine control module (ECM) determines the internal mechanical condition of the engine through
the actual measured values of the mass airflow (MAF) sensor, the intake manifold absolute pressure (MAP) sensor, and the throttle position (TP) sensor. The actual measured values of the three sensors are then compared to calculated values for V6 mode,
stored in the ECM. The ECM monitors the values for V3 mode. If any values are incorrect, the ECM will return to V6 mode operation.
Conditions for Running the DTC
| • | DTCs P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0335, and P0336 are not set. |
| • | The engine is not idling. |
| • | The engine speed is between 450-6,400 RPM. |
| • | The IAT Sensor parameter is between -7 and +125°C (+19 and +257°F) |
| • | The ECT Sensor parameter is between 70 and 125°C (158 and 257°F). |
| • | The vehicle is in drive. |
| • | Time in V6 mode is more than 2 seconds. |
| • | Time in V3 mode is more than 2 seconds. |
| • | This DTC runs continuously within the enabling conditions. |
Conditions for Setting the DTC
| • | The ECM detects that the actual measured values from the MAF sensor, the MAP, and the TP sensor, is not within the range of calculated values, for cylinder deactivation. |
| • | The above condition is met for more than 100 milliseconds. |
Action Taken When the DTC Sets
| • | DTC P3400 is a type B DTC |
| • | The cylinder deactivation will be terminated and the engine returned to normal operation. |
Conditions for Clearing the DTC
DTC P3400 is a type B DTC.
Diagnostic Aids
The valve lifer oil manifold (VLOM) solenoids are assigned to the following engine cylinders:
| • | Solenoid #1 = Cylinder #1 |
| • | Solenoid #2 = Cylinder #3 |
| • | Solenoid #3 = Cylinder #5 |
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Cylinder Deactivation (Active Fuel Management) System Description
Electrical Information Reference
Scan Tool Reference
Control Module References
for scan tool information
Circuit/System Verification
- Start and idle the engine.
- Allow the engine to reach normal engine operating temperature. The engine should idle smoothly, without any misfires. If the engine misfires, refer to
DTC P0300-P0306
.
- Monitor the cylinder deactivation system data parameters with a scan tool.
- Road test the vehicle under light throttle and load conditions that will allow the ECM to command cylinder deactivation mode. If all enabling conditions are met for cylinder deactivation, and if no internal engine hydraulic/mechanical fault conditions
are present, the ECM will continue with V3 mode operation.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
Important: Perform the Circuit/System Verification first.
Electrical System Testing
- If DTCs P3401, P3417, or P3433 are set, then refer to
DTC P3401, P3417, or P3433
.
- Ignition ON, engine OFF, command each valve lifter oil manifold (VLOM) solenoid ON, and OFF. While standing next to the engine compartment, you should be able to hear the solenoids energize, and de-energize with each command.
Mechanical System Testing
Refer to
Cylinder Deactivation (Active Fuel Management) System Diagnosis
.
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
