Circuit Description
The crankshaft position (CKP) sensor is a sensor designed to detect changes in a magnetic field. The control module supplies the CKP sensor a signal and ground circuits. Ignition voltage is supplied to the sensor by an independent circuit. The CKP sensor produces a magnetic field whenever the ignition is ON. The CKP sensor is mounted near a reluctor wheel that is attached to the crankshaft. When the crankshaft rotates, when the engine is cranking or running, the toothed reluctor wheel changes the magnetic field. The CKP sensor converts each change in the magnetic field into a PULSE. The number of teeth on the reluctor wheel determines how many pulses the CKP sensor detects per crankshaft rotation. The CKP sensor signal is used in order to determine the engine speed, the crankshaft position, and to detect misfire.
If a loss of the CKP signal or an erratic signal is detected by the VCM while the engine is running, this DTC will be set.
Conditions for Running the DTC
The MAF is 5 g/s or greater.
Conditions for Setting the DTC
The measured change in engine speed is 1,000 RPM or greater during a 125 ms time period
OR
The measured engine speed is 0 RPM and 4 or more camshaft position sensor pulses have occurred over a period of 2-3 seconds.
Action Taken When the DTC Sets
The VCM will turn ON the MIL after 2 consecutive driving cycles with the fault active.
Conditions for Clearing the MIL or DTC
| • | The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed. |
| • | A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the startup coolant temperature and the engine coolant reaches a temperature that is more than 70°C (158°F) during the same ignition cycle. |
| • | Use a scan tool in order to clear the DTCs. |
Diagnostic Aids
A poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation may cause an intermittent problem.
Thoroughly check any circuitry, that is suspected of causing the intermittent complaint for the following conditions:
| • | Backed out terminals |
| • | Improper mating |
| • | Broken locks |
| • | Improperly formed or damaged terminals |
| • | Poor terminal to wire connections |
| • | Physical damage to the wiring harness |
Inspect the face of the CKP sensor for metal shavings. This could result in an intermittent DTC P0339.
Refer to Symptoms .
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
Checks the ignition feed circuit to the crankshaft position sensor.
-
Checks the duty cycle of the crankshaft position sensor.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and the Failure Records for reference. This data will be lost when the Clear DTC Information function is used. Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||
2 | Does the vehicle start and continue to run? | -- | Go to Diagnostic Aids | |
Is the test light ON? | -- | |||
4 | Connect the test light between the CKP sensor connector terminals A and B. Is the test light ON? | -- | ||
Is the duty cycle within the specified value? | 23%-43% | |||
6 | Repair the open or short to ground in the CKP sensor ignition feed circuit. Refer to Wiring Repairs in Repair Instructions. Is the action complete? | -- | -- | |
7 | Check the CKP sensor ground circuit for an open. Was a problem found? | -- | ||
8 | Check for an open or a short in the CKP sensor (4X) signal circuit. Was a problem found? | -- | ||
9 | Check the crankshaft position (CKP) sensor and the crankshaft reluctor wheel for damage. Refer to Diagnostic Aids. Was a problem found? | -- | ||
10 |
Is the action complete? | -- | -- | |
11 | Check for a faulty connection at the CKP sensor. Was a problem found? | -- | ||
12 |
Important: Inspect the CKP sensor mounting surface to insure the surface is clean and free of debris.
Is the action complete? | -- | -- | |
13 | Check for a faulty connection at the VCM. Was a problem found? | -- | ||
14 | Repair the circuit as necessary. Refer to Wiring Repairs in Repair Instructions. Is the action complete? | -- | -- | |
15 |
Is the action complete? | -- | -- | |
16 |
Does the scan tool indicate that this diagnostic ran and passed? | -- | ||
17 | Use the scan tool in order to display the Capture Info and the Review Capture Info functions. Are there any DTCs displayed that have not been diagnosed? | -- | Go to the applicable DTC table | System OK |
