Intake camshaft sensor and exhaust camshaft sensor
The two camshaft sensor pick up the interval stage of the camshafts. To this end, an increment wheel (camshaft sensor wheel) is fixed to the camshaft. The camshaft sensor works according to the Hall effect. Voltage is supplied to the by the Digital Engine Electronics (DME) with 5 Volts. The sensor delivers a digital signal via the signal line to the Digital Engine Electronics (DME). The intake camshaft sensor is attached to the cylinder head cover. In the event of failure of the crankshaft sensor, the Digital Engine Electronics (DME) uses the signal to calculate the engine speed. The crankshaft sensor and intake camshaft sensor are necessary for the fully sequential fuel injection (fuel injection takes place individually for each cylinder at the specific ignition point).
The intake camshaft sensor enables the Digital Engine Electronics (DME) to detect whether the 1st cylinder is in the compression or exhaust stroke. In addition, this sensor delivers the feedback signal for camshaft position which controls the variable camshaft timing control (VANOS).
The intake camshaft sensor is designed as an inductive hall effect sensor. The camshaft sensor wheel has 6 different flank spacings. These flank spacings are picked up by the Hall effect sensor.
The Digital Engine Electronics (DME) uses this to calculate:
- The speed of the camshaft
- The adjustment speed of the camshaft
- The exact position of the camshaft.
| Index | Explanation |
|---|---|
| 1 | Intake camshaft sensor |
| 2 | three-pin plug connection |
For the engine start, the Digital Engine Electronics (DME) checks the following conditions:
- Error-free signal from the crankshaft sensor
- Signals must be detected in a specific chronological sequence.
This process is referred to as synchronization and is only performed when the engine is started. Only the synchronization enables the Digital Engine Electronics (DME) to activate the fuel injection correctly. The engine will not start without synchronization.
When voltage is applied, it is detected whether the sensor is above a tooth or above a gap.
The Digital Engine Electronics (DME) read in the sensor signal and then compare that signal against a template in its memory unit. This detects the exact position of the camshaft.