GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The crankshaft position (CKP) sensor is located on the rear of bank 1 of the engine block. The CKP sensor produces an AC voltage of different amplitude and frequency depending on the velocity of the crankshaft. The CKP sensor works in conjunction with a 58X reluctor wheel that is attached to the crankshaft. Each tooth on the reluctor wheel are spaced 6 degrees apart with one span having a 12 degree space. The engine control module (ECM) uses the 12 degree space to determine top dead center for cylinders 1 and 4. The ECM determines when cylinder 1 is on the compression stroke by monitoring the CKP sensor and the camshaft position (CMP) sensors. The ECM can synchronize the ignition timing, fuel injector timing, and spark knock control based on the CKP sensor and the CMP sensor inputs. If the ECM does not detect a signal from the CKP sensor, this DTC sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0335 Crankshaft Position (CKP) Sensor Circuit

Conditions for Running the DTC

    • The engine is cranking or operating.
    • The ECM detects more than 12 CMP sensor pulses.
    • DTC P0335 runs continuously once the above conditions are met for approximately 5 seconds.

Conditions for Setting the DTC

    • The ECM does not detect a signal from the CKP sensor.
        OR
    • The ECM detects that at least three reference gap position have lost.
    • The above condition exists for more than 4 seconds.

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 this information in the Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 4 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

    • Use the J 35616-A/BT-8637 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector. Using this kit prevents damage to the harness or component terminals.
    • The lower connector of the ECM is connector C1 and the upper connector of the ECM is connector C2. Refer to Front of Vehicle/Engine Compartment Component Views.
    • The ECM uses the camshaft position sensors to determine engine speed and position when there is a CKP sensor condition.
    • The engine will operate with a CKP sensor condition only if the ECM has stored the learned reference position of the camshafts in memory. With a crankshaft position sensor condition the engine will go into a limp home mode after a hard restart. The ECM then calculates engine speed from one of the camshaft position sensors. During a limp home mode the following additional DTCs may set and should be ignored:
       - DTC P0324 Knock Sensor (KS) Module Performance
       - DTC P1011 Intake Camshaft Position Actuator Park Position Bank 1
    • An intermittent condition in the CMP sensor circuits can cause a CKP DTC to set. Inspect the CMP sensor, harness connections, and related wiring, if you suspect this condition.
    • For an intermittent condition, refer to Intermittent Conditions.

Test Description

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

  1. This step determines if the condition is current.

  2. This step tests for an internal condition within the CKP sensor.

  3. This step tests if the CKP sensor is capable of generating a signal.

  4. The ECM supplies 2.5 volts to the CKP sensor circuit. If the voltage is not within range, this indicates there is a circuit or ECM condition.

  5. The ECM supplies 2.5 volts to the CKP sensor circuit. If the voltage is not within range, this indicates there is a circuit or ECM condition.

  6. This step is testing if the signal circuit and the low reference circuits of the CKP sensor are shorted together. If the DMM displays continuity, the circuits are shorted together.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Component Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Note: An intermittent condition in the camshaft position (CMP) sensor circuits could cause a CKP DTC to set. Refer to the Diagnostic Trouble Code (DTC) List - Vehicle if there are any CMP sensor DTCs stored.

  1. Attempt to start the engine.
  2. Observe the DTC Info with a scan tool.

Does the engine fail to run or does the DTC fail 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 Diagnostic Aids

4

  1. Turn OFF the ignition.
  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
  3. Disconnect the crankshaft position (CKP) sensor.
  4. Measure the resistance between the terminals of the CKP sensor with a DMM.

Is the resistance within the specified range?

700-1,200 Ω

Go to Step 5

Go to Step 11

5

  1. Connect a DMM between the terminals of the CKP sensor.
  2. Set the DMM to the AC voltage scale.
  3. Start the engine.
  4. Observe the DMM while the engine is cranking.

Is the voltage more than the specified value while the engine is cranking?

1.3 ACV

Go to Step 6

Go to Step 14

6

  1. Turn the ignition switch to ON position, with the engine OFF.
  2. Measure the voltage between the signal circuit of the CKP sensor and a good ground with a DMM.

Is the voltage within the specified range?

2-3 V

Go to Step 7

Go to Step 9

7

Measure the voltage between the low reference circuit of the CKP sensor and a good ground with a DMM.

Is the voltage within the specified range?

2-3 V

Go to Step 8

Go to Step 10

8

  1. Turn OFF the ignition.
  2. Disconnect the engine control module (ECM).
  3. Measure the resistance between the signal circuit of the CKP sensor and the low reference circuit of the CKP sensor at the ECM harness connector.

Does the DMM display OL?

--

Go to Step 13

Go to Step 15

9

Test the signal circuit of the CKP sensor for the following:

    • An open
    • A short to ground
    • A short to voltage

Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

--

Go to Step 18

Go to Step 12

10

Test the low reference circuit of the CKP sensor for the following conditions:

    • An open
    • A short to ground
    • A short to voltage

Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

--

Go to Step 18

Go to Step 12

11

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.

Did you find and correct the condition?

--

Go to Step 18

Go to Step 16

12

Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

--

Go to Step 18

Go to Step 17

13

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.

Did you find and correct the condition?

--

Go to Step 18

Go to Step 17

14

  1. Turn OFF the engine.
  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
  3. Inspect the CKP sensor for being installed correctly. Make sure the CKP sensor fastener is torqued to the specified value.

Did you find and correct the condition?

8 N·m (71 lb in)

Go to Step 18

Go to Step 16

15

Repair the short between the signal circuit of the CKP sensor and the low reference circuit of the CKP sensor.

Did you complete the repair?

--

Go to Step 18

--

16

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

Did you complete the replacement?

--

Go to Step 18

--

17

Replace the ECM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 18

--

18

  1. Clear any 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 19

19

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