D
Drive
وضع القيادة
An abbreviation for drive; one of the forward gear positions in an automatic transmission
measure of relative noise level. It is a logarithmic unit that indicates the ratio of a physical quantity (usually power or intensity) relative to a specified or implied reference level one* and it is tenth (deci) of (B) a bel
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dB* DB
Decibel
وحدة قياس الضوضاء
measure of relative noise level. It is a logarithmic unit that indicates the ratio of a physical quantity (usually power or intensity) relative to a specified or implied reference level one* and it is tenth (deci) of (B) a bel
مقياس نسبي لمستوى الضجيج/ الضوضاء. هو وحدة لوغاريتمية* تدل على نسبة الكمية الفيزيائية (عادة القدرة أو الشدة) بالنسبة إلى كمية قياسية محددة. وهي عشر (ديسي) 1/10 وحدة بيل
DC
Direct current
تيار مستمر
An electric current (flow of electrons through a wire) that moves in one direction with constant strength. Batteries are a source of direct current
هو تيار كهربائي (انسياب الالكترونات خلال سلك) يتحرك في اتجاه واحد بشدة ثابتة. البطاريات تعتبر مصدر من مصادر التيار المستمر
DCT
Double (Dual) clutch transmission
ناقل حركة بقابض مزدوج
It is a type of semi-automatic or automated manual automotive transmission (sometimes referred to as a twin-clutch gearbox). It uses two separate clutches for odd and even gear sets
DD
Direct Drive (transmission
نقل مباشر (صندوق سرعات)
DEF
Diesel Exhaust Fluid
سائل عادم الديزل
is an aqueous urea solution blended with 32.5% high purity urea and 67.5% deionized water. DEF solution is used in Selective Catalytic Reduction (SCR) to lower NOx concentration in the exhaust emissions of diesel engines. Diesel engines run with a lean (overstoichiometric) air-to-fuel ratio to ensure the combustion of soot and prevent unburnt fuel from being emitted. The excess of oxygen necessarily leads to generation of nitrogen oxides (NOx)* which are harmful pollutants* from the nitrogen in the air. Selective catalytic reduction is used to reduce the amount of NOx released into the air using DEF
DFI
Direct Fuel Injection
حقن وقود مباشر
DI (1
Direct Injection
حقن مباشر
Injecting fuel into the combustion chamber rather than the intake runner
حقن الوقود مباشرة في غرفة الاحتراق بدلا من الحقن في مجمع السحب
DI (2
Distributor Ignition
إشعال بالموزع
DIC
Driver Information Center
مركز معلومات السائق
DIS (1
Direct Ignition System
نظام إشعال مباشر
DIS (2
Distributorless Ignition System
نظام إشعال بدون موزع للشرارة
ignition system that does not use a distributor to route high voltage to the spark plugs. The high voltage plug wire runs directly from the ignition coil to the spark plug. Some DIS systems have one coil for every two spark plugs (a shared system)* while others have a separate coil for each spark plug (See Coil-On-Plug Ignition). Eliminating the distributor makes the system more reliable and eliminates maintenance
DIY
do-it-yourself job
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DLC
Data Link Connector
وصلة الحصول على المعلومات
is the multi-pin diagnostic connection port for automobiles and trucks used to interface a scan tool with the control modules of a given vehicle and access On-Board Diagnostics and live data stream
DLI
Distributorless Ignition system
نظام إشعال بدون موزع
n ignition system that does not use a distributor to route high voltage to the spark plugs. The high voltage plug wire runs directly from the ignition coil to the spark plug. Some DIS systems have one coil for every two spark plugs (a shared system)* while others have a separate coil for each spark plug (Coil-On-Plug Ignition). Eliminating the distributor makes the system more reliable and eliminates maintenance.
DMM
Digital multi meter
مقياس رقمي متعدد القياس
Also* called digital volt/ohmmeter (DVOM
DMV
Department of Motor Vehicles
قسم المركبات الآلية (السيارات)
In the United States a department of motor vehicles (DMV) is a state-level government agency that administers vehicle registration and driver licensing
DOD (DoD
Displacement on demand
تعديل سعة المحرك عن الحاجة
Shuts down cylinders in an engine when not needed* typically at highway cruise. Sometimes called Cylinder Deactivation* Multiple Displacement System (MDS)* Active Fuel Management* or Variable Cylinder Management
تبطيل عمل اسطوانات بالمحرك عند عدم الحاجة إليها* خاصة عند السير على الطرق السريعة. ويطلق عليها عدة أسماء منها: تبطيل الاسطوانات* نظام متعدد الإزاحة* الإدارة الفعالة في الوقود* إدارة سعة الاسطوانات
DOE
Department Of Energy
The U.S. Department of Energy
قسم الطاقة
DOHC
Dual Over Head Cam
نظام عمود كامة علوي مزدوج
DOHC dual overhead cam engine has two camshafts in cylinder head. Cams act directly on valves without rocker arms. One cam operate the intake valves the other operate the exhaust valves
هو نظام له عمودين للكامة يركب في رأس المحرك. حيث تأثر الكامات مباشرة على الصمامات بدون استخدام أذرع متأرجحة. عمود كامة لتشغيل صمامات السحب* والعمود الأخر لتشغيل صمامات العادم
DOT
The U.S. Department of Transportation
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DOT 3* DOT 4* DOT 5
دوط 3* دوط 4* دوط 5
DOT 3 BRAKE FLUID; Brake fluid that meets the Department of Transportation specifications for glycol based fluids with a wet boiling point (lowest allowable after it’s been in use) of 284 degrees F. and a dry boiling point of 401 degrees F. DOT 3 fluid is the type commonly specified by most vehicle manufacturers. Because it is glycol based* it absorbs moisture over time (hygroscopic). This lowers its effective boiling point and promotes internal corrosion in the brake system. For this reason* the brake fluid should be replaced periodically (every two years is recommended by many experts) and every time the brakes are relined or serviced. DOT 4 BRAKE FLUID; A "heavy-duty" glycol based brake fluid with a slightly higher wet boiling point of 311 degrees F. and a dry boiling point of 446 degrees. This type of fluid is sometimes specified for performance vehicles or those subject to high brake temperatures. DOT 5 BRAKE FLUID; A silicone based fluid that does not absorb moisture and has a boiling point of at least 500 degrees F. DOT 5 fluid does not have to be changed periodically and can minimize brake system corrosion* but is very expensive compared to DOT 3 or DOT 4 fluid (it costs three to five times as much). It will not mix with DOT 3 or DOT 4 brake fluid. DOT 5 is NOT recommended for any vehicle with ABS brakes because it tends to aerate when cycled rapidly through small orifices
DPF
Diesel Particulate Filter
منقي الجسيمات للديزل
is a device designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine
هو منقي (فلتر) يعمل على منع ملوثات الجسيمات الصلبة والهباب من غازات عادم محركات الديزل
DSC
Dynamic Stability Control
is a suspension control system helps prevent understeer or oversteer by managing the braking force and engine torque delivered to individual wheels. DSC helps the car to stay on track under any road conditions
DSG
Direct Shift Gearbox
نقل مباشر لصندوق التروس
DSG removes the clutch pedal and associated operation* and places it under the control of computer chips and hydraulic servos. When left in full auto mode* it's as smooth as or smoother than any conventional automatic
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DTCs
Diagnostic Trouble Cods
رمز (شفرة) تشخيص العطل
Computerized engine control systems have a certain amount of built-in self-diagnostic capability to detect problems that affect engine performance and emissions. The same is true for the antilock brake system and other onboard systems that are computer controlled. When a fault is detected* the computer will store a diagnostic trouble code in its memory and illuminate the "Check Engine" light. On some vehicles* the computer can be put into a special diagnostic mode by grounding certain terminals on a diagnostic connector. This will cause the Check Engine or other lights to flash out the fault code. On many vehicles* though* a scan tool must be plugged into the computer system to access and read the codes
DUI
Driving Under the Influence
القيادة تحت تأثير الكحول
It is the act of driving a motor vehicle with blood levels of alcohol in excess of a legal limit ("Blood Alcohol Content"* or "BAC"). In most jurisdictions a measurement such as a blood alcohol content (BAC) in excess of a specific threshold level* such as 0.05% or 0.08% defines the offense
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DWS
Deflation Warning System
نظام تحذير أنخفاض ضغط الإطار
developed by Dunlop for on-line detection of tire pressure loss. When tire pressure is reduced* the tire circumference is also reduced resulting in increased wheel rpm. The system uses the wheel speed sensors of an existing ABS system to continuously monitor wheel speed and tire condition* and triggers a warning signal upon detecting a problem
هو نظام من ابتكار شركة دنلوب للكشف عن انخفاض ضغط الإطار. عند انخفاض ضغط الإطار* فإن محيط الإطار يقل بالتالي ويؤدي إلى زيادة سرعة دوران العجل. يستخدم النظام حساسات سرعة العجل الموجودة بنظام منع غلق العجلات لرصد سرعة دوران العجلات بشكل مستمر وبالتالي حالة نفخ الإطار* ويقوم النظام بتحذير السائق في حالة زيادة سرعة الإطارات عن سرعة معينة والتي تعني انخفاض ضغط الإطار عن ضغط معين
DYC
Direct Yaw-moment Control
التحكم المباشر في عزم دوران السيارة
Direct yaw-mometn control system is proposed to improve the handling and stability of a four-independent-wheel drive electric vehicle. The DYC system distributes torque and power to each wheel motor to meet the requirements of each wheel