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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Corvette 🢒 DTC 🢒 DTC P0335 Crankshaft Position (CKP) Sensor Circuit

Object Number: 66350 Size: SF
OBD II Symbol Description Notice
Engine Controls Components
Cell 20: CKP, CMP, KS and Traction Control System
Handling ESD Sensitive Parts Notice

Circuit Description

The Crankshaft Position Sensor CKP is mounted in the right rear of the engine block behind the starter. The CKP sensor works in conjunction with a 24X reluctor wheel mounted on the rear of the crankshaft. The CKP sensor has a B+ power supply, a ground, and a signal circuit.

As the crankshaft rotates, the reluctor wheel teeth interrupt a magnetic field produced by a magnet within the sensor. The sensor's internal circuitry detects this and produces a signal which the PCM reads. The PCM uses this signal to accurately measure crankshaft velocity which is a variable used in order to detect misfire, spark and, fueling.

Conditions for Running the DTC
    • DTCs P0101, P0102, P0103, P0341, P0342, P0343 are not set.
    • Camshaft Position sensor is transitioning.
    • Ignition Voltage is between 5.0 and 17.0 volts.
    • MAF is greater than 3 g/s.
    • The ignition switch in the crank mode.

Conditions for Setting the DTC

The PCM determines that no output from the CKP sensor signal for less than 3 seconds.

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

Conditions for Clearing the MIL/DTC
    • A last test failed, or the current DTC, clears when the diagnostic runs and does not fail.
    • A history DTC clears after 40 consecutive warm-up cycles, if failures are not reported by this or any other emission related diagnostic.
    • Use a scan tool in order to clear the MIL/DTC.

Diagnostic Aids

Important: Remove any debris from the PCM\TAC module connector surfaces before servicing the PCM\TAC module. Inspect the PCM\TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM\TAC modules.

This DTC may not report a pass. The scan tool status for this DTC will never report a pass so it will appear that the diagnostic never runs. This will cause the MIL to remain ON until a DTC clear command or battery disconnect occurs.

The following problems may cause this DTC to set:

    • Poor connections/terminal tension at the sensor
    • Crankshaft reluctor wheel damage or improper installation
    • The sensor coming in contact with the reluctor wheel
    • The engine running out of fuel.

Using Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can aid in determining how many miles since the DTC set. The Fail Counter and Pass Counter can also aid determining how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed. For an intermittent condition, refer to Symptoms .

Excess crankshaft end play will cause the CKP sensor reluctor wheel to move out of alignment with the CKP sensor. This could result in any one of the following:

    • A no start
    • A start and stall
    • Erratic performance

An improperly installed propeller shaft could cause excess crankshaft end play. Refer to Engine Mechanical for excess crankshaft end play diagnosis.

For an intermittent, refer to Symptoms .

Test Description

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

  1. This step verifies that the fault is present.

    2.

  2. If the duty cycle is present at the PCM connector, the Camshaft Position sensor B+ reference and ground circuits are OK.

    3.

  3. This step checks the Camshaft Position sensor B+ reference circuit.

    4.

  4. This step checks the Camshaft Position sensor ground circuit.

    5.

  5. This step checks for a short to B+ on the Camshaft Position sensor signal circuit.

    6.

  6. This step checks for a short to ground on the Camshaft Position sensor signal circuit.

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Install a scan tool.
  2. Idle the engine.
  3. Monitor the CAM signal input - High to Low transition in the Engine Data List 1 using the scan tool.

Does the scan tool parameter increment?

--

Go to Step 3

Go to Step 4

3
  1. Turn ON the ignition leaving the engine OFF.
  2. Review the Freeze Frame and/or Failure Records data for this DTC and observe the parameters.
  3. Turn OFF the ignition for 15 seconds.
  4. Idle the engine.
  5. Operate the vehicle within the conditions required for this diagnostic to run, and as close to the conditions recorded in Freeze Frame/Failure Records as possible. Special operating conditions that you need to meet before the PCM will run this diagnostic, where applicable, are listed in Conditions for Setting the DTC.
  6. Select the Diagnostic Trouble Code (DTC) option, the Specific DTC option, then enter the DTC number using the scan tool.

Does the scan tool indicate that this diagnostic failed this ignition?

--

Go to Step 4

Go to Diagnostic Aids

4

  1. Disconnect the PCM connector located on the opposite side of the manufacturer's logo. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .
  2. Install the brown terminal from the terminal kit J 35616 into the Camshaft Position sensor signal circuit (PCM harness side).
  3. Probe the Camshaft Position sensor signal circuit with one lead of the DMM and connect the other lead to a ground.
  4. Select the duty cycle option on the DMM.
  5. Crank the engine.

Does the DMM display a duty cycle within the specified range?

45% - 55%

Go to Step 17

Go to Step 5

5

  1. Turn OFF the ignition.
  2. Reconnect the PCM connector.
  3. Remove the intake manifold in order to gain access to the Camshaft Position sensor. Refer to Engine/Engine Mechanical for the procedure.
  4. Disconnect the Camshaft Position sensor electrical connector.
  5. Turn ON the ignition leaving the engine OFF.
  6. Measure the voltage from the Camshaft Position sensor B+ reference circuit to the battery ground using the DMM J 39200 .

Does the DMM display the specified voltage?

B+

Go to Step 6

Go to Step 8

6

Measure the voltage from the Camshaft Position sensor B+ reference circuit to the Camshaft Position sensor ground circuit using the DMM J 39200 .

Does the DMM display the specified voltage?

B+

Go to Step 9

Go to Step 7

7
  1. Check for an open in the Camshaft Position sensor ground circuit.
  2. If you find a circuit problem, repair the circuit as necessary. Refer to Body and Accessories/Wiring Systems.

Did you find and correct the condition?

--

Go to Step 20

Go to Step 17

8
  1. Check for an open or a short to ground in the Camshaft Position sensor B+ reference circuit.
  2. If you find a circuit problem, repair the circuit as necessary. Refer to Body and Accessories/Wiring Systems.

Did you find and correct the condition?

--

Go to Step 20

Go to Step 17

9

  1. Turn ON the ignition leaving the engine OFF.
  2. Measure the voltage at the Camshaft Position sensor signal circuit to ground using the DMM J 39200 .

Is the voltage less than the specified value?

1.0V

Go to Step 10

Go to Step 14

10

Probe the Camshaft Position sensor signal circuit using the Test Lamp connected to battery positive voltage.

Does the Test Lamp illuminate?

--

Go to Step 15

Go to Step 11

11
  1. Turn OFF the ignition.
  2. Disconnect the PCM connector located on the opposite side of the manufacturer's logo. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .
  3. Check the continuity of the signal circuit from the sensor harness connector to the PCM using the DMM J 39200 .

Is the resistance less than the value specified?

5ohms

Go to Step 18

Go to Step 16

12

Repair the open or short to ground in the Camshaft Position sensor B+ reference circuit. Refer to Body and Accessories/Wiring Systems.

Is the action complete?

--

Go to Step 20

--

13

Repair the open in the Camshaft Position sensor ground circuit. Refer to Body and Accessories/Wiring Systems.

Is the action complete?

--

Go to Step 20

--

14

Repair the short to voltage in the Camshaft Position sensor signal circuit. Refer to Body and Accessories/Wiring Systems.

Is the action complete?

--

Go to Step 20

--

15

Repair the short to ground in the Camshaft Position sensor signal circuit. Refer to Body and Accessories/Wiring Systems.

Is the action complete?

--

Go to Step 20

--

16

Repair the open in the Camshaft Position sensor signal circuit. Refer to Body and Accessories/Wiring Systems.

Is the action complete?

--

Go to Step 20

--

17

Check the connections at the PCM. Refer to Body and Accessories/Wiring Systems.

Did you find and correct the condition?

--

Go to Step 20

Go to Step 19

18

Important: Before replacing the CMP sensor, inspect the harness connector for proper terminal tension. Refer to Body and Accessories/Wiring Systems.

Replace the Camshaft Position sensor. Refer to Camshaft Position Sensor Replacement .

Is the action complete?

--

Go to Step 20

--

19

Important : Program the replacement PCM. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .

Replace the PCM.

Is the action complete?

--

Go to Step 20

--

20
  1. Select the Diagnostic Trouble Code (DTC) option and the Clear DTC Information option using the scan tool.
  2. Idle the engine at the normal operating temperature.
  3. Select the Diagnostic Trouble Code (DTC) option and the Specific DTC option, then enter the DTC number using the scan tool.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text, if applicable.

Does the scan tool indicate that this test ran and passed?

--

Go to Step 21

Go to Step 2

21

Select the Capture Info option and the Review Info option using the scan tool.

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

--

Go to applicable DTC Table

System OK