Diagnostic Instructions
DTC Descriptor
DTC P0335: Crankshaft Position (CKP) Sensor Circuit
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
5-Volt Reference
| P0335
| P0335
| --
| P0336
|
CKP Sensor Signal
| P0335
| P0335
| P0335
| P0336
|
Low Reference
| --
| P0335
| --
| P0336
|
Circuit/System Description
The crankshaft position (CKP) sensor circuits consist of an engine control module (ECM) 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 of the teeth and slots of a 58-tooth reluctor wheel on the crankshaft. Each tooth on the reluctor wheel is spaced at 60-tooth spacing, with 2 missing teeth for the reference gap. The CKP sensor
produces an ON/OFF DC voltage of varying frequency, with 58 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 reluctor wheel, to the ECM as each tooth on the wheel rotates past the CKP sensor. The ECM uses each CKP signal pulse to determine crankshaft speed and decodes the crankshaft reluctor wheel reference gap to identify crankshaft position. This information
is then used to determine the optimum ignition and injection points of the engine. The ECM also uses CKP sensor output information to determine the camshaft relative position to the crankshaft, to control camshaft phasing, and to detect cylinder misfire.
Conditions for Running the DTC
| • | The engine is cranking or running. |
| • | DTC P0335 runs continuously when the above condition is met. |
Conditions for Setting the DTC
| • | The ECM detects an incorrect number of CKP pulses during engine cranking for 4 seconds. |
| • | The ECM detects an incorrect number of CKP pulses while the engine is running for 2 seconds. |
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp
(MIL) on the second consecutive ignition cycle that the diagnostic runs and
fails. |
| • | The control module records the operating conditions at the time
the diagnostic fails. The first time the diagnostic fails, the control module
stores this information in the Failure Records. If the diagnostic reports
a failure on the second consecutive ignition cycle, the control module
records the operating conditions at the time of the failure. The control
module writes the operating conditions to the Freeze Frame and updates
the 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. |
Diagnostic Aids
| • | When the ECM enables starter operation, the ECM also initiates the diagnostic test routines for the CKP and camshaft position (CMP) sensors. If the ignition switch is in the start position for more than 4 seconds without the engine cranking,
the CKP diagnostics may fail and set this DTC. |
| • | Insufficient fuel may cause this DTC to set. |
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Attempt to start the engine. Observe the CKP Active Counter with a scan tool.
| ⇒ | If the CKP Active Counter does not increment, continue with Circuit/System Testing. |
Circuit/System Testing
- With the ignition OFF, disconnect the harness connector at the CKP sensor.
- With the ignition ON, measure for 4.8-5.2 volts, between the 5-volt reference circuit of the CKP sensor and ground.
| ⇒ | If the voltage is less than 4.8 volts, test for a short to ground, open/high resistance at the circuit. If the circuit tests normal, replace the control module. |
- With the ignition ON, measure for 4.8-5.2 volts between the 5-volt reference circuit of the CKP sensor and the low reference circuit of the CKP sensor.
| ⇒ | If the voltage is less than 4.8 volts, test for an open/high resistance at the circuit. If the circuit tests normal, replace the control module. |
- With the ignition ON, momentarily connect a test lamp between the CKP sensor signal circuit and the 5-volt reference circuit of the CKP sensor. The fuel pump should operate when the test lamp is applied to the CKP sensor signal circuit.
| ⇒ | If the fuel pump does not operate when the test lamp is applied to the CKP sensor signal circuit, test for a short to ground, open/high resistance, short to voltage at the circuit. If the circuit tests normal, replace the control module. |
- Remove the CKP sensor.
- Inspect the CKP sensor for the following conditions:
| • | Excessive play or looseness |
| • | Foreign material passing between the CKP sensor and the reluctor wheel |
| • | Electromagnetic interference in the CKP sensor circuits |
- Inspect the CKP reluctor wheel for the following conditions:
| • | Excessive end play or looseness |
- If all circuits and components test normal, replace the CKP sensor.
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
