For 1990-2009 cars
CMP and CKP Sensors
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

### Circuit Description

The crankshaft position (CKP) sensor is used to indicate the crankshaft position so that the powertrain control module (PCM) can determine which cylinder is misfiring when a misfire is present. The CKP sensor receives a 6 pulse signal from the crankshaft reluctor wheel.

### Condition for Running the DTC

The engine must be running.

### Conditions for Setting the DTC

No signal from the CKP sensor with the PCM receiving 20 pulses from the camshaft position (CMP) sensor.

### Action Taken When the DTC Sets

• | The PCM illuminates the malfunction indicator lamp (MIL).

• | The PCM records the operating conditions at the time the diagnostic fails. This information is stored in the Freeze Frame buffer.

### Conditions for Clearing the MIL/DTC

• | The MIL turns off after 3 consecutively passing trips without a fault present.

• | A history DTC clears after 40 consecutive warm-up cycles without a fault.

• | Perform the scan tool Clear DTC Information function in order to clear the DTC.

### Diagnostic Aids

Check for any of the following conditions:

• | The CKP sensor performance may be affected by temperature. Check the sensor operation and the internal resistance at various temperatures.

• | Check the wiring harness boot covering the CKP sensor electrical connectors for water intrusion. Water entry into the CKP sensor electrical connections may cause an intermittent loss of the CKP sensor signal.

• | Check the CKP sensor signal rotor for foreign material or damaged teeth.

• | A DTC P0335 that sets while driving and checks OK may be caused by inadequate CKP sensor circuit shielding. Check that the CKP sensor circuit is properly shielded and that the drain wire has a good ground.

An intermittent malfunction may be caused by a fault in the CKP sensor circuit. Inspect the wiring harness and components for any of the following conditions:

• | Any backed-out terminals

• | Any improper mating of terminals

• | Any broken electrical connector locks

• | Any improperly formed or damaged terminals

• | Any faulty terminal-to-wire connections

• | Any physical damage to the wiring harness

• | A broken wire inside the insulation

• | Any corrosion of the electrical connections, the splices, or the terminals

If no problem is found with the CKP sensor or the circuitry, check the crankshaft timing belt pulley for foreign material or damaged teeth.

If a DTC P0335 is intermittent, driving the vehicle under the following conditions can verify whether the fault is present. Perform the scan tool Clear DTC Information function. Road test the vehicle while monitoring the DTC P0335 diagnostic on the scan tool under the Not Ran Since Code Cleared selection in the DTC Information menu. If a DTC P0335 appears in the Not Ran Since Code Cleared list, the P0335 diagnostic has not yet run. When the DTC P0335 does not appear in the Not Ran Since Code Cleared list, the P0335 diagnostic has run. If the MIL is NOT illuminated, and there is no Pending DTC Status in DTC Information, the P0335 diagnostic has passed. The DTCs MUST be cleared in order to view the Current Status of the Not Ran Since Code Cleared list. DO NOT forget that the Not Ran Since Code Cleared list only indicates that the test has run, not whether the test passed or failed. The DTC Information screen must be checked for Current or Pending status in order to determine the outcome of the diagnostic test involved.

If the DTC P0335 cannot be duplicated, the information included in the Freeze Frame data can be useful in determining vehicle operating conditions since the DTC was first set.

### Test Description

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

1. The Powertrain (OBD) System Check prompts the technician to complete some basic checks and to store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.

2. Determine if a fault is present. Review the Freeze Frame data in order to determine when the DTC set. Always record this information.

3. If the CKP sensor is within the specified value, measure the resistance from the CKP sensor side of each terminal to ground. The CKP sensor's resistance should be 1M ohms or more. If not replace the CKP sensor.

4. Check for an open or a short in the CKP sensor's high and low reference circuits between the PCM and the CKP sensor.

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. Turn ON the ignition, leaving the engine off.
2. Perform the scan tool Clear DTC Information function.
3. Operate the vehicle within the Freeze Frame conditions as observed.

Is DTC P0335 set?

--

Go to Step 3

Go to Diagnostic Aids

3 |

1. Turn OFF the ignition.
2. Disconnect the CKP sensor pigtail connector located below the intake manifold.
3. Measure the resistance of the CKP sensor using a digital multimeter (DMM).

Is the resistance within the specified range?

484-656 ohms at 20°C (68°F)

Go to Step 4

Go to Step 6

4 |

1. Disconnect the PCM electrical connectors.
2. Check the CKP sensor high and low signal circuits for an open or a short.
3. Repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a repair necessary?

--

Go to Step 8

Go to Step 5

5 |

1. Check for faulty electrical terminal connections at the PCM and at the CKP sensor.
2. Repair as necessary.

Was a repair necessary?

--

Go to Step 8

Go to Step 7

6 | Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement . Is the action complete? | -- | Go to Step 8 | --
7 | Important: The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Is the action complete? | -- | Go to Step 8 | --
8 |

1. Perform the scan tool Clear DTC Information function and road test the vehicle within the Freeze Frame conditions that set the DTC.
2. Review the scan tool data.
3. Check for DTCs. The repair is complete if no DTCs are stored.

Are any DTCs displayed on the scan tool?

--

Go to Diagnostic Trouble Code (DTC) List

System OK