Tài liệu học tập cơ bản khái quát về động cơ và các bộ phận trên ô tô phiên bản tiếng anh. Tài liệu này nhằm giúp chúng ta tiếp cận được cấu tạo chức năng của các bộ phận của xe. Với tài liệu này giúp các bạn sinh viên ngành cơ khí ô tô tiếp cận được những kiến thức cơ bản về ô tô và đồng thời nâng cao kiến thức tiếng anh. Bộ tài liệu này được soạn thảo bởi trường đào tạo và huấn luyện nghề ở Canada.
Chapter 21 Electrical Instrumentation Instrument Panels • Dashboard is called the instrument panel • Consists of gauges, switches, and controls Types of Displays • Analog – An indicator moves in front of a fixed scale to indicate a condition • Digital – Uses numbers or graphic symbols instead of a moving needle Analog Display Digital Display Instrument Gauges • Provide scaled information • Require voltage regulators and sending units • Instrument voltage regulators (IVRs) stabilize and limit voltage to gauges • Gauge input is from a sending unit Magnetic Gauges • Magnet attracts ferrous needle • Armature field opposes PM • Attractive or repulsive forces move needle Instrument Gauges (cont’d) • Two Coil (Balancing Coil) Gauge – Uses the interaction of two electromagnets and the total field effect on an armature to cause needle movement Balancing Coil Gauge Instrument Gauges (cont’d) • Bimetallic Gauges – Are sometimes called thermoelectric gauges – Use two dissimilar metals to transform the heating effect of electricity into mechanical movement – Some use an instrument voltage regulator (IVR) to provide a constant voltage to the gauge Indicator and Warning Lights (cont’d) • Antilock Light – Indicates an ABS fault • Brake Pad Indicator – Brake sensors sense thin brake pad lining • Stop Light Warning Light – Illuminates if a brake light is inoperative Indicator and Warning Lights (cont’d) • Traction/Stability Control Lamp – Indicates a problem in the traction and/or stability control system • Check Engine Light – On late model vehicles this indicates an emissions system related fault has occurred Indicator and Warning Lights (cont’d) • Oil Pressure Light – May be red or yellow depending on oil pressure • Charge Indicator Light – If charging system voltage is below battery voltage this light will illuminate • Check Filler Cap – Check and tighten fuel filler cap Indicator and Warning Lights (cont’d) • Low Fuel Warning – Indicates fuel level is below one quarter full • Add Coolant Lamp – Illuminates if coolant level is low • Maintenance Reminder – Mileage triggered light to have vehicle inspected and serviced Sound Warning Devices • Used to remind drivers of certain vehicle conditions – – – – – Fasten seat belts Air bag operational Key left in ignition Door ajar Lights left on Driver Information Centers • Various gauges, warning lights, and controls may be grouped together • May also provide fuel range, economy, and usage details • Can show average vehicle speeds, oil life index, and various engine-operating parameters Hybrid Vehicles • Honda – Displays status of hybrid system, fuel economy, battery status, and charge/assist • Toyota – Pressure sensitive touch screen – Energy monitor display General Diagnosis and Testing • • • • • • Fuses Indicator bulbs Detector switches (indicator systems) Sender units (gauge systems) IVR (gauge systems) Gauges (gauge systems) Intermittent Problem Causes • • • • • • Poor mating of connector halves Backed out terminals Wire chafing Connector body damage Dirty or corroded terminals Poor wire-to-terminal connections