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 P0335 Crankshaft Position (CKP) Sensor Circuit

Conditions for Running the DTC

    • The engine is cranking or running.
    • The camshaft position (CMP) sensor signal is present.

Conditions for Setting the DTC

The ECM determines no signal from the CKP sensor for less than 8 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 Freeze Frame/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.

Step

Action

Values

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

Attempt to start the engine.

Does the engine start and run?

--

Go to Intermittent Conditions

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the crankshaft position (CKP) sensor harness connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the 12-volt reference circuit of the CKP harness connector and a good ground.

Does the test lamp illuminate?

B+

Go to Step 4

Go to Step 7

4

  1. Turn OFF the ignition.
  2. Connect a jumper wire between each of the terminals in the CKP sensor harness connector and the corresponding terminal at the CKP sensor. Refer to Using Connector Test Adapters in Wiring Systems.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the low reference circuit of the CKP sensor at the jumper wire terminal to a good ground with a DMM. Refer to Measuring Voltage Drop in Wiring Systems.

Is the voltage more than the specified value?

0.2 V

Go to Step 6

Go to Step 5

5

  1. Turn OFF the ignition.
  2. Remove the jumper wires from the CKP sensor harness connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Observe the crank signal present parameter with a scan tool.
  5. With a fused jumper wire connected to the signal circuit of the CKP sensor harness connector, momentarily and repeatedly probe B+.

Does the crank signal present parameter change when the jumper wire contacts B+ repeatedly?

--

Go to Step 9

Go to Step 8

6

Test the low reference circuit for an open or high resistance. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 11

7

Test the 12-volt reference circuit for an open, high resistance or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 11

8

Test the CKP signal circuit for an open, short to ground or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 14

9

Test the CKP signal circuit for high resistance. Refer to Circuit Testing , Testing for Short to Ground and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 10

10

Inspect for poor connections at the CKP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 12

11

Inspect for poor connections at the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 14

12

  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. • 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 16

Go to Step 13

13

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 16

Go to Step 15

14

Replace the ECM. Refer to Engine Control Module Replacement .

Did you complete the replacement?

--

Go to Step 16

--

15

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

Did you complete the replacement?

--

Go to Step 16

--

16

  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 17

17

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