P0366
DTC P0341, P0346, P0366, or P0391
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0341
- Intake Camshaft Position (CMP) Sensor Performance Bank 1
DTC P0346
- Intake Camshaft Position (CMP) Sensor Performance Bank 2
DTC P0366
- Exhaust Camshaft Position (CMP) Sensor Performance Bank 1
DTC P0391
- Exhaust Camshaft Position (CMP) Sensor Performance Bank 2
Diagnostic Fault Information
Circuit/System Description
The 4X camshaft position (CMP) sensor circuits consist of an engine control module (ECM) supplied 5-volt reference circuit, low reference circuit, and an output signal circuit. The CMP sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes of the teeth and slots of a 4-tooth reluctor wheel attached to the camshaft. As each reluctor wheel tooth rotates past the CMP sensor, the resulting change in the magnetic field is used by the sensor electronics to produce a digital output pulse. The sensor returns a digital ON/OFF DC voltage pulse of varying frequency, with 2 narrow, and 2 wide output pulses per camshaft revolution that represent an image of the camshaft reluctor wheel. The frequency of the CMP sensor output depends on the velocity of the camshaft. The ECM decodes the narrow and wide tooth pattern to identify camshaft position. This information is then used to determine the optimum ignition timing and fuel injection points of the engine. The ECM also uses CMP sensor output information to determine the camshaft relative position to the crankshaft, to control the CMP actuator if equipped, and for limp-home operation.
Conditions for Running the DTC
* The engine is running.
* DTC P0641 or P0651 are not set.
* The DTC runs continuously when the above conditions are met.
Conditions for Setting the DTC
* Less than 4 or more than 10 CMP sensor pulses during the first 2 engine revolutions.
* The ECM detects that the engine is running, but receives approximately 400 CMP pulse per 200 engine cycles.
Action Taken When the DTC Sets
* DTCs P0341, P0346, P0366, P0391 are Type B DTCs.
* The CMP actuator is commanded to the parked position.
* A fault on one intake CMP sensor will park both intake camshaft actuators. A fault on one exhaust CMP sensor will park both exhaust camshaft actuators.
Conditions for Clearing the DTC
DTCs P0341, P0346, P0366, P0391 are Type B DTCs.
Diagnostic Aids
With a DTC set, the engine may crank for an extended period of time during start-up.
Reference Information
Schematic Reference
Engine Controls Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Electronic Ignition (EI) System Diagnosis (Electronic Ignition (EI) System Diagnosis)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
J 35616 Connector Test Adapter Kit
Circuit/System Verification
1. Ignition OFF, inspect the engine wiring harness carrying the CMP sensor circuits for the following conditions:
* Close routing of aftermarket electrical equipment
* Close to solenoids, motors, and relays
• Correct any wire harness routing or component placement conditions, if it is determined to be a possible source of electrical interference.
2. Observe that the following parameters are all incrementing:
* Exhaust CMP bank 1 active
* Intake CMP bank 1 active
* Exhaust CMP bank 2 active
* Intake CMP bank 2 active
3. Engine running, observe the DTC information with a scan tool. DTCs P0340, P0341, P0345, P0346, P0365, P0366, P0390, or P0391 should not set.
4. 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
1. Ignition OFF, inspect the CMP sensor for correct installation.
• If the CMP sensor is loose, inspect the sensor and the O-ring for damage, replace as necessary.
2. Inspect the engine for the following conditions:
* Engine oil for debris
* Camshaft reluctor wheel for damage
* The timing chain, tensioner and sprockets for wear or damage
• If debris is found in the engine oil, inspect the internal engine components to determine the root cause. Repair or replace any worn or damaged components.
Component Testing
Important: You must perform the Circuit/System Testing before proceeding with Component Testing.
1. Inspect the CMP sensor for correct installation. Remove the CMP sensor from the engine and inspect the sensor O-ring for damage.
• If the sensor is loose, incorrectly installed, or damage, replace the CMP sensor.
2. Connect the CMP sensor harness connector to the CMP sensor.
3. Ignition ON, engine OFF. Observe the CMP Active Counter parameter on the scan tool.
4. Pass a flat steel object repeatedly across the tip of the sensor that faces the reluctor wheel. The CMP Active Counter parameter should increment with each pass of the steel object.
• If the parameter does not increment, replace the CMP sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust (Service and Repair)
* Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake (Service and Repair)
* Camshaft Position Sensor Replacement - Bank 1 (Right Side) Exhaust (Service and Repair)
* Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake (Service and Repair)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming