GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 Acadia - 2WD 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC P0016, P0017, P0018, or P0019

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category

DTC Descriptors

DTC P0016: Crankshaft Position (CKP) - Intake Camshaft Position (CMP) Correlation Bank 1

DTC P0017: Crankshaft Position (CKP) - Exhaust Camshaft Position (CMP) Correlation Bank 1

DTC P0018: Crankshaft Position (CKP) - Intake Camshaft Position (CMP) Correlation Bank 2

DTC P0019: Crankshaft Position (CKP) - Exhaust Camshaft Position (CMP) Correlation Bank 2

Circuit/System Description

The engine control module (ECM) uses the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor pulses to monitor the correlation between the crankshaft and camshaft position. The crankshaft reluctor wheel consists of a 60-tooth pattern with 2 teeth missing for a reference gap. Each tooth is evenly spaced 6 degrees apart, except for the reference gap. The camshaft reluctor wheel has 4 teeth, 2 narrow and 2 wide. The 4 trailing edges of each tooth are evenly spaced 90 camshaft degrees apart. As the crankshaft rotates with the CMP actuator in the home or parked position, the ECM expects CMP sensor pulses to occur 36 crankshaft degrees before top dead center (BTDC) at cylinder number 1, and every 90 camshaft degrees thereafter.

Conditions for Running the DTC
    • DTC P0335, P0336, P0340, P0341, P0345, P0346, P0365, P0366, P0390, P0391, P0641, or P0651 is not set.
    • The engine is running.
    • The engine speed is less than 1,200 RPM and the CMP actuator is commanded to the home or parked position.
    • The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM detects that the CMP sensor pulses occur less than or more than 9 crankshaft degrees outside of the normal position for 25 out of 35 engine cycles.

Action Taken When the DTC Sets
    • DTC P0016, P0017, P0018, P0019 are Type B DTCs.
    • The CMP actuators are commanded to the home or parked position.

Conditions for Clearing the MIL/DTC

DTC P0016, P0017, P0018, P0019 are Type B DTCs.

Diagnostic Aids

A camshaft actuator stuck in the full actuation position may cause the engine to crank but not start.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

    •  Engine Control Module Connector End Views
    •  Engine Controls Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

Description and Operation

    •  Engine Control Module Description
    •  Camshaft Actuator System Description
    •  Lubrication Description

Circuit/System Verification

    Important: The supply of clean pressurized engine oil to the CMP actuator is essential to CMP actuator performance.

  1. Observe the engine oil level. The engine oil level should be within operating range. Refer to Approximate Fluid Capacities .
  2. Ensure that the vehicle has the correct engine oil and is not old, burnt or contains additives. Refer to Checking Things Under the Hood in Service and Appearance Care within the Owner's Manual.
    3. ⇒If the vehicle has the incorrect engine oil, is old, burnt, or contains additives then change the oil and filter.
  3. Test the engine oil pressure for correct operation. Refer to Oil Pressure Diagnosis and Testing .
  4. Allow the engine to reach operating temperature.
    5. ⇒If the engine cranks but does not run, observe the CMP variance parameter while cranking. The CMP variance parameter should be 0 degrees.
  5. Set the parking brake and place the vehicle in park for automatic, or neutral for manual.
  6. Observe the CMP variance parameter. The CMP Variance will rise for 1-2 seconds until the CMP Angle parameter matches the Desired CMP parameter. The CMP Variance should again return to 0 degrees.

    7. Important: The engine will run rough and may require throttle input to keep running.

  7. Command the CMP actuator to 20 degrees. The Desired CMP parameter should match the CMP Angle parameter.

Circuit/System Testing
    • Inspect the engine or review the service history of the vehicle for any recent repairs involving the timing chain, camshaft, or crankshaft.
       ⇒If recent repairs were made, refer to Camshaft Timing Drive Components Cleaning and Inspection and inspect the timing chain and sprockets for proper alignment.
    • Inspect the CMP actuator. Refer to the camshaft position actuators in Camshaft Timing Drive Components Cleaning and Inspection and Engine Front Cover Cleaning and Inspection .
    • Inspect the engine timing components. Refer to Camshaft Timing Drive Components Cleaning and Inspection .

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Camshaft Timing Drive Components Cleaning and Inspection for timing chain, sprockets, and CMP actuator filter screen replacement