The camshaft position sensor works the same way as the crank sensor so that it has also a 3-wire hall-effect sensor which is connected to the PCM (powertrain control module). Using a target magnet attached to the end of the camshaft, it has four different poles. As the camshaft rotates, so does the magnet. The cam sensor has identical electrical circuits going to it, similar to the crank sensor, 9-volt power supply, 5-volt signal line, and sensor ground. As the cam (and magnet) rotate, the 5-volt signal line voltage fluctuates from 5 volts to 0 volts. Once the PCM has both sensor inputs, it can determine which coil to control and which injector to energize.
The location of the cam position sensor (CMP) varies with the type of engine and ignition system. On DI systems, the cam sensor is integrated into the distributor; on other applications, it is located on the front of the engine and gets its reference signal from the cam sprocket.
When working on remote type cam sensor, do a visual inspection of the reluctor teeth. Any high spots of the reluctor teeth can interrupt the magnetic field of the coil and the magnet. When these interruptions happens, it is transmitted from the pickup coil to the engine control unit (ECU).
On distributor type cam sensors, use a scan tool to monitor the cam counts and set them as close to zero as possible by adjusting or repositioning the distributor. When replacing the synchronizer shaft and the cam sensor, a special alignment tool is required. Please contact ATS for the specialized tool needed for synchronization.
Friday, October 8th, 2010 AT 5:58 AM