Online customer service
Customer service team:
Online customer service
Service time:
8:00 - 22:00



Welcome to inquire


News details

Camshaft position sensor principle and inspection and maintenance

2019/07/20 12:47
Page view
Camshaft position sensor is one of the most important sensors in the control system. It is usually installed in the distributor.
The camshaft position sensor, also known as the synchronous signal sensor, is a cylinder discriminating positioning device that inputs the camshaft position signal to the ECU, which is the main control signal for ignition control.
A straight shaft is generally equipped with a number of cams, straight shaft through mechanical transmission and the detection of equipment, with the device's rotation on the circumference of a fixed position.The CAM will be mechanically attached to the desired position, allowing it to break or close to signal control of the device.
The function of the camshaft position sensor is to collect the position signal of the distribution camshaft and input ECU, so that the ECU can identify the upper dead center of cylinder 1 compression, so as to carry out sequential injection control, ignition time control and deflagration control.
In addition, camshaft position signal is also used to identify the first ignition moment when the engine starts.Because the camshaft position sensor can identify which cylinder the piston is about to reach TDC, it is called the cylinder identification sensor.
When the fault of camshaft position sensor interrupts the signal, the fault information can be detected by the diagnostic instrument, which shows the fault of camshaft position sensor.It includes two detection methods:
1. Detection of sensor power supply voltage
Disconnect the ignition switch, press the connector plug of the sensor conductor, and connect the positive and negative meters of the multimeter with terminals 1 and 3 respectively. When the ignition switch is connected, the voltage shall be more than 4.5v.If the voltage is zero, the wiring harness is broken or short-circuited.Or the ECU is out of order;After the ignition switch is disconnected, continue to detect whether the wire is broken or short.
2, wire resistance detection
Check the resistance of sensor terminal 1 and ECU terminal 62, sensor terminal 2 and ECU terminal 76, sensor terminal 3 and ECU terminal 67 with the resistance of the multimeter. The resistance value between each wire should not be greater than 1.5 ohms.If the resistance is too large or infinite, the wiring harness is not in good contact or the wire is broken. Repair or replace the wiring harness.
Previous article: