• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
5-Volt Reference Circuit | P0641, P0651 | P0335 | P0651, P2135 | -- |
CKP Sensor Signal Circuit | P0335 | P0335 | P0335 | P0336 |
Low Reference | -- | P0335 | P0335 | -- |
Circuit | Normal Range | Short to Ground | Open | Short to Voltage |
---|---|---|---|---|
Operating Conditions: Engine Running | ||||
5-Volt Reference Circuit | 400-6,400 RPM | 0 RPM | 0 RPM | 0 RPM |
CKP Sensor Signal Circuit | 400-6,400 RPM | 0 RPM | 0 RPM | 0 RPM |
Low Reference | 400-6,400 RPM | -- | 0 RPM | 0 RPM |
The engine control module (ECM) uses the crankshaft position (CKP) sensor pulses to monitor the crankshaft position. The crankshaft reluctor wheel consists of a 60-tooth pattern with 2 teeth missing for the reference gap. Each tooth is evenly spaced 6 degrees apart, except for the reference gap. The engine control module (ECM) provides a 5-volt reference to the sensor a low reference circuit and a signal circuit. As the crankshaft rotates the reluctor trigger wheel interrupts a magnetic field provided by a magnet internal to the sensor. The CKP sensor internal circuitry detects this interruption of the magnetic field and produces an ON/OFF DC voltage of varying frequency. The frequency of the CKP sensor output signal is dependent upon crankshaft speed. The ECM uses each CKP output signal to determine crankshaft speed and identify crankshaft position. The information from the CKP sensor and other engine sensors is used to determine the optimum fuel injection and ignition system timing events for efficient engine operation. The ECM also uses the CKP sensor output information to determined the camshaft relative position to the crankshaft position, cylinder misfire and if equipped to control the intake and exhaust valve timing through the camshaft actuator assembly.
• | DTC P0340, P0341, P0641, or P0651 is not set. |
• | The engine is cranking or running. |
• | The DTC runs continuously when the above conditions are met. |
Important: The ECM detects engine movement by sensing the airflow through the mass air flow (MAF) sensor is more than 3 g/s, or by sensing camshaft position (CMP) sensor pulses. |
• | The ECM detects that the starter is commanded ON, and the engine has been cranking for more than 4 seconds without a CKP sensor pulse. |
• | The ECM detects that the engine has been running but has not received a CKP sensor pulse for 2 out of 10 engine revolutions. |
Important: The ECM detects engine movement by sensing the airflow through the mass air flow (MAF) sensor is more than 3 g/s or by sensing CMP sensor pulses. |
• | The ECM detects that the engine is running but receives less than 51 or more than 65 CKP sensor pulses during each engine revolution, for 8 of 10 engine revolutions. |
• | The ECM detects that the engine is running but more than 19 crankshaft resyncs have occur within 25 seconds. |
DTC P0335 or P0336 are type B DTC
DTC P0335 or P0336 are type B DTC.
• | This test procedure requires that the vehicle battery has passed a load test and is completely charged. |
• | When disconnecting harness connectors or removing fuses and relays from a fuse block, always inspect the component electrical terminals for corrosion and the mating electrical terminals for tightness. |
⇒ | If the CKP sensor is zero or grossly different from the Engine Speed parameter then continue with the Circuit/System Testing. |
⇒ | If the CKP sensor plot line changes from the Engine Speed plot line, continue with the Circuit/System Testing. |
⇒ | If the vehicle passes the above Circuit/System Verification Tests, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List. Another option is to refer to Testing for Intermittent Conditions and Poor Connections. |
• | Close routing of secondary ignition wires. |
• | Close routing of aftermarket electrical equipment. |
• | Close to motors, solenoids, and relays. |
⇒ | Correct any wire routing or component placement conditions, if is determined to be a possible source of electrical interference. |
⇒ | If the voltage is less than 4.8 volts, test for a short to ground or an open/high resistance in the 5-volt reference circuit between the ECM and the CKP sensor connector. If the circuit tests normal, replace the ECM. |
⇒ | If the voltage is less than 4.8 volts, test for an short to ground or an open/high resistance in the CKP sensor signal circuit between the ECM and the CKP sensor wire harness connector. If the circuit tests normal, replace the ECM. |
⇒ | If the voltage is more than 5.2 volts, test for a short to voltage in the CKP sensor signal circuit between the ECM and the CKP sensor wire harness connector. If the circuit tests normal, replace the ECM. |
⇒ | If the amperage is more than 3 mA, test the CKP sensor signal circuit for a short to the 5-volt reference circuit between the ECM and the CKP sensor connector. If the circuit tests normal, replace the ECM. |
⇒ | If the CKP Active Counter parameter does not increment, replace the ECM. |
⇒ | If the voltage measured between the low reference circuit and the battery positive post is not the same as the voltage measured between a known ground and the battery post, then test for an open/high resistance in the low reference circuit between the ECM and the CKP sensor connector. If the circuit tests normal, replace the ECM. |
⇒ | If the parameter remains at zero or another fixed value, replace the CKP sensor. |
⇒ | If debris is found in the engine oil, inspect the engine components to determine the cause. |
⇒ | If the crankshaft reluctor wheel is damaged, replace the crankshaft. |
⇒ | If any parts are worn or damaged, replace as necessary. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup and programming |