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P0335






P0335-CRANKSHAFT POSITION SENSOR CIRCUIT

For a complete wiring diagram, refer to the Wiring Information.





Theory of Operation

The Crankshaft Position (CKP) Sensor circuits consist of a Powertrain Control Module (PCM) supplied 5-Volt reference circuit, low reference circuit and an output signal circuit. The CKP Sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes between the peaks and valleys of a tone wheel on the crankshaft. Each tooth on the tone wheel is spaced with missing teeth for the reference gap. The CKP Sensor produces an ON/OFF DC voltage of varying frequency, reference output pulses per crankshaft revolution. The frequency of the CKP Sensor output depends on the velocity of the crankshaft. The CKP Sensor sends a digital signal, which represents an image of the crankshaft tone wheel, to the PCM as each tooth on the wheel rotates past the CKP Sensor. The PCM uses each CKP signal pulse to determine crankshaft speed and decodes the crankshaft tone wheel reference gap to identify crankshaft position. This information is then used to sequence the ignition timing and fuel injection events for the engine. The PCM also uses CKP Sensor output information to determine the crankshaft relative position to the camshaft, to detect cylinder misfire and to control the CMP actuator if equipped.

- When Monitored:
With the engine cranking or running.

- Set Condition:
No CKP signal is present during engine cranking and at least eight camshaft position sensor signals have occurred. One Trip Fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

Diagnostic Test

1. CHECK FOR APPLICABLE TSB
1. Check for any applicable TSBs that may apply for this issue.

Were any TSBs applicable?

Yes

- Perform the applicable TSB. Erase the DTC and perform the verification test.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 2

2. DTC IS ACTIVE
1. Turn the ignition on.
2. Read and copy the DTC's and Freeze Frame Data.
3. Start the engine, or crank the engine for 10 seconds.

NOTE:
If the vehicle starts and runs, wiggle test the wiring and see if problem duplicates or the fault sets.

Is the status Active for this DTC?

Yes

- Go To 5

No

- Go To 3

3. WIRE HARNESS/CKP SENSOR INSPECTION
1. Turn the ignition off.
2. Disconnect the harness connectors at the PCM and Crank Sensor and inspect for wire chaffing or rub conditions, terminals pushed out on the wiring connector, bent terminals at the PCM and Crank Sensor, water in the connector cavities, presence of corrosion on the terminals of the connectors or components.
3. Visually inspect the mounting area of Crank Sensor for debris/damage or a loose sensor. Remove the Crank Sensor and inspect the end of the sensor for signs of damage or debris. Rotate the engine and if possible, inspect the target wheel for any signs of damage. Reinstall the Crank Sensor and ensure that the sensor is properly installed and torqued to proper specification.

NOTE:
Due to the fact that this DTC is set by an intermittent loss of the signal, the most likely cause is a poor connection at the Crank Sensor or PCM terminals, or a poor signal between the Crank Sensor and target wheel. Because of this, unplugging and reconnecting the harness connectors, or repositioning the Crank Sensor will often repair the condition that set the DTC.

Were any problems found?

Yes

- Perform the appropriate repair.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 4

4. CHECK THE VEHICLE'S REPAIR HISTORY
1. Check the history of the vehicle for previous crank sensor related DTCs within the past 90 days.

Did the repair history show that the vehicle was in dealership for a crank sensor fault within the past 90 days?

Yes

- Replace the Crank Sensor.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Test complete. Reconnect the harness connectors, and erase the DTC. The most likely cause was a poor connection at one of the harness connectors. Verify the DTC does not return.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

5. CHECK THE (F855) 5-VOLT SUPPLY CIRCUIT VOLTAGE
1. Turn the ignition off.
2. Disconnect the CKP Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (F855) 5-Volt Supply circuit at the CKP Sensor harness connector.

Is the voltage between 4.8 and 5.2 volts?

Yes

- Go To 6

No, voltage is below 4.8 volts:

- Repair the 5-Volt Supply circuit for an open or short to ground.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No, voltage is above 5.2 volts:

- Repair the 5-Volt Supply circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

6. CHECK THE (K24) CKP SIGNAL CIRCUIT VOLTAGE
1. Measure the voltage of the (K24) CKP Signal circuit at the CKP Sensor harness connector.

Is the voltage between 4.8 and 5.2 volts?

Yes

- Go To 7

No

- Go To 9

No

- Repair the CKP Sensor Signal circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

7. CHECK THE (K925) SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance of the (K925) CKP Sensor Ground circuit between the CKP Sensor harness connector and the PCM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 8

No

- Repair the (K925) CKP Sensor Ground circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

8. TONE WHEEL/PULSE RING INSPECTION
1. Turn the ignition off.
2. Disconnect the battery ground cable.
3. Remove the CKP Sensor.
4. Visually inspect the sensor mounting location for damage, foreign material.
5. Rotate the engine and if possible inspect the target wheel for any signs of damage.

Were any problems found?

Yes

- Repair Issues in mounting location. Repair or replace the Tone Wheel / Pulse Ring as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace the Crank Position Sensor.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

9. CHECK THE (K24) CKP SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance between ground and the (K24) CKP Signal circuit at the Crankshaft Position Sensor harness connector.

Is the resistance above 10K Ohms?

Yes

- Go To 10

No

- Repair the (K24) CKP Signal circuit for a short to ground.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

10. CHECK THE (K24) CKP SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K24) CKP Signal circuit between the Crankshaft Position Sensor harness connector and the PCM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 11

No

- Repair the (K24) CKP Signal circuit for an open circuit or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

11. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Crankshaft Position Sensor and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the CKP Sensor and Powertrain Control Module connectors.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.

NOTE:
Due to the fact that this DTC is set by an intermittent loss of the signal, the most likely cause is a poor connection at the Crank Sensor or PCM terminals, or a poor signal between the Crank Sensor and target wheel. Because of this, unplugging and reconnecting the harness connectors, or repositioning the Crank Sensor will often repair the condition that set the DTC.

Were any problems found?

Yes

- Perform the appropriate repair.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace and program the Powertrain Control Module (PCM). .
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

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