You will need
- - multimeter (tester);
- - Allen wrench
Please note: the car access to the knock sensor complicates the intake module. As a result, remove the knock sensor to the touch. To facilitate the process, remove the splash shield of the engine and remove the sensor, get close to him from the bottom of the car (on a viewing hole or overpass).
For removing the knock sensor Unscrew the Allen key sensor retaining bolt from the cylinder block. Remove the sensor from the mounting studs and remove it from under the intake module. Disconnect the harness connector from the sensor by pressing the locking button.
To test the sensor, connect its findings multimeter included in the mode voltmeter with a measuring range up to 200 mV. For a proper connection, one-touch sensor to the device, the negative lead (black) connect the device with the weight sensor (installation location of the bolt). The positive wire (red) connect signal wire located in the connector of the sensor. Two-pin sensors, connect both pins to the wires of the tester with the correct polarity.
Then with a screwdriver lightly tap on the sensor body, mimicking the detonation. The tester should show voltage spikes size 40-200 mV depending on the force of the concussion. If any malfunction of the sensor reaction to the shock will not. The sensor should be replaced. Remember that in some cases, the devices are not able to detect a weak signal and Vollmer will malfunction the sensor.
Set the tester mode to measure resistance and connect it to the terminals of the sensor. It is desirable that the device had the ability to measure an infinitely large resistance. Defective knock sensor on the car must have very high resistance tending to infinity.
A more accurate test of the knock sensor is only possible on a special stand. Proven sensor install in the reverse order. Mounting bolt tighten to 20-25 Nm.