Car sensor!
CarsensorYescarThe input device of the computer system, which converts various operating conditions of the vehicle, such as vehicle speed, temperature of various media, and engine operating conditions, into electrical signals and output to the computer, so that the engine is in the best working condition.CarsensorIn many cases, when judging the failure of the sensor, one should not only consider the sensor itself, but the entire circuit where the failure occurred.Therefore, when looking for a fault, in addition to checking the sensor, you must also checkWire harness, Connectors and related circuits between the sensor and the electronic control unit. Let's get to know the main sensors on the car.
Air flow sensor
The air flow sensor converts the inhaled air into an electrical signal and sends it to the electronic control unit (ECU) as one of the basic signals for determining fuel injection. According to different measurement principles, it can be divided into rotating wing air flow sensor (Toyota PREVIA station wagon), Carmen vortex air flow sensor (Toyota Lexus LS400 sedan), hot wire air flow sensor (Nissan Maxima's VG30E engine and domestically produced There are four types of Volvo B230F engine installed on Tianjin Sanfeng Bus TJ6481AQ4) and hot film air flow sensor. The first two are volume flow types, and the latter two are mass flow types. Currently, hot wire air flow sensors and hot film air flow sensors are mainly used.
IntakePressure Sensor
The intake air pressure sensor can be measured according to the load state of the engineIntake manifoldThe absolute pressure inside and convert it into an electrical signal andRotating speedThe signals are sent to the computer together as the basis for determining the basic fuel injection volume of the fuel injector. The domestically-made Audi 100 sedan (V6 engine), Santana 2000 sedan, Beijing Cherokee (25L engine), Toyota Crown 3.0 sedan, etc. all use this pressure sensor.Currently widely used is semiconductor varistorresistanceType intake air pressure sensor.
Throttleposition sensor
FestivalValveThe position sensor is installed on the throttle to detect the opening of the throttle. It is linked with the throttle through a lever mechanism to reflect the different operating conditions of the engine. This sensor can detect different working conditions of the engine and input it into the electronic control unit (ECU) to control different fuel injection quantities. It has three types:switchContact type throttle position sensor (Santana 2000 sedan and Tianjin Sanfeng bus), linear variable resistance throttle position sensor (Beijing Cherokee), comprehensive throttle position sensor (domestic Audi 100 V6 engine).
Crankshaftposition sensor
Also calledCrankshaftRotation angle sensor, computer controlledIgnition systemThe most important sensor is to detect the top dead center signal, the crank angle signal and the engine speed signal, and input them into the computer, so that the computer can issue the best ignition timing command according to the ignition sequence of the cylinders. There are three types of crankshaft position sensors: electromagnetic pulse type crankshaft position sensor, Hall effect type crankshaft position sensor (Santana 2000 sedan and Beijing Cherokee), photoelectric effect type crankshaft position sensor. Different types of crankshaft position sensors have different control methods and control accuracy.The crankshaft position sensor is generally installed on the crankshaftbeltThe side of the wheel or sprocket, and some are installed onCamshaftFront end, some are also installed inDistributor(Santana 2000 sedan).
Knock sensor
The knock sensor is installed on the cylinder block of the engine to monitor the knock of the engine at any time. At present, there are two types of resonance and non-resonance!
Email: