Volvo

The camshaft position (CMP) sensor is an inductive device. As the camshaft turns, the tip of the CMP sensor senses the teeth of the tone wheel fastened to the camshaft vibration damper. The CMP sensor sends a series of voltage pulses to the Engine Control Module (ECM). The frequency of the pulses is translated into engine speed (RPM) and position by the ECM. The ECM uses this information along with the information from Crankshaft Position (CKP) sensor to synchronize fuel injection. Conditions for diagnostic trouble code (DTC):1) Engine Control module (ECM) detects extra pulses on the crankshaft position (CKP) signal...

The Crank Speed Sensor is an inductive sensor that will generate a variable voltage signal when the sensor’s magnetic field is excited. When the engine is running the flywheel’s teeth rotate past the sensor’s tip and voltage pulses are generated. The Engine Control Module (ECM) monitors the frequency of the signal generated by the Crank Speed Sensor and calculates the engine RPM. Conditions for diagnostic trouble code (DTC):1) Incorrect crankshaft position (CKP) sensor signal Observable symptoms1) Long start time2) Uneven operation3) Loss of power4) Malfunction indicator lamp (MIL) illuminated Probable cause1) Flywheel sensor2) Wiring harness3) Flywheel4) Electrical interference in the...

The Crank Speed Sensor is an inductive sensor that will generate a variable voltage signal when the sensor’s magnetic field is excited. When the engine is running the flywheel’s teeth rotate past the sensor’s tip and voltage pulses are generated. The Engine Control Module (ECM) monitors the frequency of the signal generated by the Crank Speed Sensor and calculates the engine RPM. Conditions for diagnostic trouble code (DTC):1) No signal Observable symptoms1) Long start time2) Uneven operation3) Malfunction indicator lamp (MIL) illuminated Probable cause1) Flywheel sensor2) Wiring harness3) Incorrectly installed sensor (incorrect distance to tooth wheel)4) ECM: Engine Control Module...

The Crank Speed Sensor is an inductive sensor that will generate a variable voltage signal when the sensor’s magnetic field is excited. When the engine is running the flywheel’s teeth rotate past the sensor’s tip and voltage pulses are generated. The Engine Control Module (ECM) monitors the frequency of the signal generated by the Crank Speed Sensor and calculates the engine RPM. Conditions for diagnostic trouble code (DTC):1) Incorrect crankshaft position (CKP) sensor signal Observable symptoms1) Long start time2) Uneven operation3) Loss of power Probable cause1) Flywheel sensor2) Wiring harness3) Flywheel4) Electrical interference in the crankshaft position (CKP) sensor signal5)...

The J1939 data lines consist of an expandable data bus allowing the addition of accessory control modules. The J1939 data lines are the primary data bus. Data is prioritized and then transmitted across the J1939 data lines to the appropriate control module. Conditions for diagnostic trouble code (DTC):1) CAN communication does not work Observable symptoms1) An electronic control unit (ECU) lacking communication with other ECUs can cause a number of symptoms Probable cause1) Internal fault in electronic control unit (ECU)2) Connector3) Data link Detailed information1) Faults on the datalink can be localised by combining this diagnostic trouble code (DTC) with...