GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The engine control module (ECM) uses the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor signals to monitor the correlation between the crankshaft and camshaft positions. If the ECM detects that the timing between the crankshaft and the camshaft is incorrect, DTC P0016 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0016 Crankshaft Position (CKP) Camshaft Position (CMP) Correlation

Conditions for Running the DTC

    • The engine is cranking, or the engine is running.
    • DTCs P0335, P0336, P0340, P0341 are not set.
    • DTC P0016 runs continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM detects that the timing between the crankshaft and the camshaft is incorrect for one cam trigger pulse.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores the information in the Freeze Frame/Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC last test failed clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles if no failures are reported by this or any other emission related diagnostic.

Test Description

The number below refers to the step number on the diagnostic table.

  1. An incorrectly installed camshaft gear, crankshaft sprocket, or timing chain can cause this DTC to set.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Start the engine.
  2. Allow the engine to reach normal operating temperature.
  3. Observe the DTC information with a scan tool.

Does the scan tool display DTC P0016 failed this ignition?

Go to Step 4

Go to Step 3

3

  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  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.

Did the DTC fail this ignition?

Go to Step 4

Go to Testing for Intermittent Conditions and Poor Connections

4

Observe the DTC information with a scan tool.

Does the scan tool display that DTC P0335, P0336, P0340, or P0341 also failed this ignition?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 5

5

Repair one of the following conditions:

    • The camshaft gear and the crankshaft sprocket alignment marks are not aligned properly
    • A timing chain tensioner condition
    • An incorrectly installed timing chain
    • Excessive play in the timing chain
    • Incorrect indexing of the timing mark on either the crankshaft sprocket or the camshaft gear

Refer to the following procedures:

Did you complete the repair?

Go to Step 6

--

6

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  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.

Did the DTC fail this ignition?

Go to Step 2

Go to Step 7

7

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK