GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The hall effect crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. There are 57 teeth on the front of the crankshaft sprocket, plus a sync gap. The CKP sensor will output an ON-OFF pulse as each window passes the sensing element. The CKP sensor is connected directly to the engine control module (ECM) by the following circuits:

    • The 12-volt reference circuit
    • The low reference circuit
    • The CKP sensor signal circuit

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0336 Crankshaft Position (CKP) Sensor Performance

Conditions for Running the DTC

The engine is cranking or running.

Conditions for Setting the DTC

The ECM determines that the CKP sensor signal is out of range for less than 2 seconds.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (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.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

    • An intermittent CKP sensor signal may cause DTC P0336 to set. Wiggle the wiring harness with the engine running and observe the CKP Signal Missed parameter of the scan tool. If the parameter indicates anything other than 0, there is an intermittent condition. Refer to Testing for Intermittent Conditions and Poor Connections and Inducing Intermittent Fault Conditions in Wiring Systems.
    • If the condition is intermittent, refer to Intermittent Conditions .

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 - Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

  1. Observe the Freeze Frame/Failure Records data 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 3

Go to Diagnostic Aids

3

  1. Inspect all of the circuits going to the crankshaft position (CKP) sensor for the following:
  2. • Routed too closely to fuel injection wiring or components
    • Routed too closely to after-market add-on electrical equipment
    • Routed too closely to solenoids, relays, and motors
  3. If you find incorrect routing, correct the harness routing.

Did you find and correct the condition?

Go to Step 10

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the CKP sensor.
  3. Test the CKP sensor signal circuit for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 5

5

Test for an intermittent and for a poor connection at the CKP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 6

6

Test for an intermittent and for a poor connection of the CKP sensor circuits at the engine control module (ECM). Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 7

7

  1. Remove the CKP sensor. Refer to Crankshaft Position Sensor Replacement .
  2. Visually inspect the CKP sensor for the following conditions:
  3. • Physical damage
    • Loose or improper installation
    • Wiring routed too closely to secondary ignition components
  4. The following conditions may cause this DTC to set:
  5. • Excessive air gap between the CKP sensor and the reluctor wheel
    • Electromagnetic interference in the CKP sensor circuits
    • Foreign material passing between the CKP sensor and the reluctor wheel
    • Insufficient fuel

Did you find and correct the condition?

Go to Step 10

Go to Step 8

8

Inspect the CKP reluctor wheel for the following conditions:

    • Physical damage
    • Improper installation
    • Excessive endplay or looseness

Refer to Crankshaft Reluctor and Oil Pump Drive Gear Replacement in Engine Mechanical - 6.6L.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

9

Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement .

Did you complete the replacement?

Go to Step 10

--

10

  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 11

11

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK