Liquid crystal instrument for automobile
1 Scope
This document specifies terms and definitions, requirements, test methods and inspection rules of Liquid crystal instrument for automobile.
This document is applicable to TFT liquid crystal instruments for Categories M and N automobiles (including speedometer, odometer, tachometer, fuel meter, thermometer, oil pressure gauge, voltmeter, ammeter, SOC meter, endurance odometer, urea level meter and barometer). It may serve as a reference for other types of display instruments.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 2423.17-2008 Environmental testing for electric and electronic products - Part 2: Test methods - Test Ka: Salt mist
GB 4094 Symbols for controls, indicators and tell-tales of motor vehicles
GB/T 4094.2-2017 Electric vehicles - Part -2017: Symbols for controls, indicators and tell-tales
GB/T 6739 Paints and varnishes - Determination of film hardness by pencil test
GB/T 16422.2-2014 Plastics - Methods of the Exposure to Laboratory Light Sources - Part 2: Xenon-arc sources
GB/T 18910.61-2021 Liquid crystal display devices - Part 6-1: Measuring methods for liquid crystal display devices - Photoelectric parameter
GB/T 18655 Vehicles, Boats and Internal Combustion Engines - Radio Disturbance Characteristics - Limits and Methods of Measurement for The Protection of On-Board Receivers
GB/T 19951 Road vehicles - Disturbances test methods for electrical/electronic component from electrostatic discharge
GB/T 21437.2-2008 Road vehicles - Electrical disturbances from conduction and coupling - Part 2: Electrical transient conduction along supply lines only
GB/T 21437.3-2012 Road vehicles - Electrical disturbances from conduction and coupling - Part 3: Electrical transient transmission by capacitive and inductive coupling via lines other than supply lines
GB/T 28046.2-2019 Road vehicles - Environmental conditions and testing for electrical and electronic equipment - Part 2: Electrical loads
GB/T 28046.3-2011 Road vehicles - Environmental conditions and testing for electrical and electronic equipment - Part 3: Mechanical loads
GB/T 28046.4-2011 Road vehicles - Environmental conditions and testing for electrical and electronic equipment - Part 4: Climatic loads
GB/T 28046.5-2013 Road vehicles - Environmental conditions and testing for electrical and electronic equipment - Part 5: Chemical loads
GB/T 30038-2013 Road vehicles - Degrees of electrical equipment protection (IP-Code)
QC/T 413 -2002 Basic technical requirements for automotive electric equipment
QC/T 550 Vehicle buzzer
QC/T 727 Instrument for automobile and motorcycle
SJ/T 11394 Measure Methods of Semiconductor Light Emitting Diodes
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
liquid crystal instrument for automobile
instrument assembly (including full liquid crystal instrument and combined liquid crystal instrument) which is composed of at least one liquid crystal screen and comprehensively reflects the vehicle condition to the driver by means of information display and alarm
3.2
full liquid crystal instrument
liquid crystal instrument assembly that does not have a physical pointer and displays information such as numbers and symbols to the driver mainly through a liquid crystal screen
3.3
combined liquid crystal instrument
instrument assembly with LCD screen, traditional pointer instrument panel or other display modes
3.4
liquid crystal display
display device that uses the photoelectric effect of liquid crystal to convert changes in electric field, light, etc. into visual signals to display information, including segment code liquid crystal display (LCD), dot matrix LCD, TFT LCD and so on
3.5
TFT liquid crystal display
active matrix addressable liquid crystal display with thin film transistors, each pixel controlled by one (or more) thin film transistor switches
3.6
start time
time from the start of power-on to the stable display of vehicle information on the screen
3.7
response time
pointer or number that smoothly indicates the time required to reach the position corresponding to the upper limit value (or the lower limit value) when the signal steps from the lower limit value to the upper limit value (or the upper limit value to the lower limit value)
4 Requirements
4.1 Appearance
4.1.1 Transparent glass or transparent plastic parts shall be free from bubbles, inclusions, ripples, spots and scratches that affect readings. The protective layer shall be uniform, with no obvious defects such as bubbles, spots, rust and shedding. LCD shall be free from rupture and deformation. All components cooperate well, without loosening, falling off and visible foreign bodies.
4.1.2 Indexing lines, pointers, numbers, characters and symbols shall be clear and complete, without refraction and reading distortion.
4.1.3 The lighting effect shall ensure that the indexing lines, pointers, numbers and text symbols of various instruments can be clearly seen, and there shall be no glare of strong light.
4.1.4 If the signal indicator lamp is lit, all kinds of indication signals, symbols, patterns and colors on the instrument shall be clear and complete without light channeling. If the signal indicator lamp goes out, the signal state shall be obviously different from that when it is lit.
Contents
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Requirements
5 Test methods
6 Inspection rules
7 Marking, packaging, storage and preservation
Annex A (Informative) Display symbols of the instrument panel
Annex B (Informative) Diagram of instrument connection
