GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. The CKP sensor is connected directly to the powertrain control module (PCM), and consists of the following circuits:

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

Conditions for Running the DTC

    • DTCsP0101, P0102, P0103, or P0341 are not set.
    • The camshaft position sensor (CMP) is transitioning.
    • The mass airflow (MAF) is more than 3 g/s in Crank mode.
    • The MAF is more than 5 g/s in Run mode.

Conditions for Setting the DTC

The CKP sensor signal is not detected for more than 3 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.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step determines if the DTC P0336 is an intermittent.

  2. This step checks the ignition 1 voltage circuit to the CKP.

  3. This step checks the CKP low reference circuit.

  4. This step checks the CKP.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Does the vehicle start and continue to run?

--

Go to Intermittent Conditions

Go to Step 3

3

  1. Disconnect the CKP.
  2. Turn ON the ignition, with the engine OFF.
  3. Probe the CKP sensor harness connector 12-volt reference circuit with a test lamp connected to a ground.

Does the test lamp illuminate?

--

Go to Step 4

Go to Step 6

4

Connect a test lamp between the 12-volt reference circuit in the CKP sensor harness connector and the sensor low reference circuit.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 7

5

  1. Turn OFF the ignition.
  2. Connect the gray jumpers from the J 35616 Connector Test Kit between the engine harness connector and the sensor connector of the 12-volt reference circuit and low reference circuit.
  3. Connect a DMM set to the duty cycle position between the sensor signal circuit and a ground circuit. Select AC voltage and press the Hz button twice in order to display the duty cycle.
  4. Crank the engine.

Is the duty cycle within the specified range?

40-60%

Go to Step 8

Go to Step 9

6

Repair the open or high resistance in the 12-volt reference circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 15

--

7

  1. Repair the open or high resistance in the low reference circuit.
  2. Repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 13

8

  1. Repair the open, high resistance, and short in the sensor signal circuit.
  2. Repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 11

9

Check the CKP sensor and the crankshaft reluctor wheel for damage. Refer to Crankshaft Position Sensor Replacement or Crankshaft Position Sensor Reluctor Ring Replacement .

Did you find and correct the condition?

--

Go to Step 10

Go to Step 12

10

Replace the CKP sensor or the crankshaft reluctor wheel. Refer to Crankshaft Position Sensor Replacement or Crankshaft Position Sensor Reluctor Ring Replacement in Engine Mechanical.

Did you complete the replacement?

--

Go to Step 15

--

11

  1. Check for a faulty connection at the CKP sensor.
  2. Repair the connector as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 13

12

Important: Inspect the CKP sensor mounting surface in order to verify that the surface is clean and free of debris.

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

Did you find and correct the condition?

--

Go to Step 15

--

13

  1. Check for a faulty connection at the powertrain control module (PCM).
  2. Repair the connector as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 14

14

Replace the PCM. Refer to Powertrain Control Module Replacement .

Did you complete the replacement?

--

Go to Step 15

--

15

  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC run and pass?

--

Go to Step 16

Go to Step 2

16

With the scan tool, observe the stored information, Capture Info.

Does the scan tool display any DTCs that you have not diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK