楊四軍武科大教授單元五汽車電氣設(shè)備(課件)-《汽車專用英語 第三版》同步教學(xué) （人交版）

汽車商標(biāo)汽車及其歷史汽車發(fā)動(dòng)機(jī)汽車底盤單元一單元二單元三單元四汽車電氣設(shè)備汽車車身汽車使用說明書及維修手冊(cè)汽車檢測(cè)與維修設(shè)備單元五單元六單元七單元八汽車維護(hù)汽車檢測(cè)與維修新能源汽車概述汽車商務(wù)接待單元九單元十單元十一單元十二

單元五

活塞連桿組故障診斷與修復(fù)汽車電氣設(shè)備

學(xué)習(xí)目標(biāo)

完成本學(xué)習(xí)任務(wù)后，你應(yīng)該能：1.了解汽車電氣設(shè)備的基本結(jié)構(gòu)及其工作原理；2.掌握汽車電氣設(shè)備術(shù)語的英語表達(dá)；3.對(duì)相關(guān)內(nèi)容進(jìn)行閱讀和翻譯；4.對(duì)汽車電氣設(shè)備上英文單詞或詞匯進(jìn)行辨認(rèn)；5.正確完成課后練習(xí)。建議學(xué)時(shí)6

學(xué)時(shí)Text

Theelectricalsystemisoneofthebasicpartsofanautomobile.Itcangenerate,store,anddistributealltheelectricitythatautomobileneeds.Theelectricalsystemofamodernautomobileiscomposedoftwomajorparts:thepowersupplyandthecurrentconsumers.TheformerincludesthestoragebatteryandalternatorThelatterincludestheenginestartingsystem,thegasolineengineignitionsystemandotherelectricinstallments.Thustheautomobileelectricalsystemcanbedividedintofourmajorcomponents：startingsystem,chargingsystem,ignitionsystemandaccessorysystem.AutomobileElectricalSystemText

StartingSystemThevehicle'sstartingsystem(Fig.5-1)isdesignedtoturnor“crank”theengineoveruntilitcanoperateunderitsownpower.Todothis,thestartermotorreceiveselectricalpowerfromthestoragebattery.Andthenthestartermotorconvertsthisenergyintomechanicalenergy,whichistransmittedthroughthedrivemechanismtotheengine'sflywheel.AutomobileElectricalSystemText

StartingSystem

AutomobileElectricalSystemFig.5-1StartingSystemText

StartingSystemAtypicalstartingsystemhasfivebasiccomponentsandtwodistinctelectricalcircuits.Thecomponentsareasfollowing:1.Battery(Fig.5-2)2.Batterycables3.Keyswitch(ofstartingswitch)4.Startermotor(Fig.5-3)5.MagneticswitchAutomobileElectricalSystemFig.5-2BatteryFig.5-3StarterMotorText

StartingSystemAbatteryisanelectrochemicaldevice.Carbatteriesareofthe12Vtype.Thebatterysuppliescurrenttoenergizethemagneticfieldofthealternatorinitially.Duringcharging,thebatterychangeselectricalenergyfromthealternatorintochemicalenergytomaintainitsstateofcharge.Whenoverloaded,thebatteryandthegeneratorworktogethertopowerthevehicle.Thebatteryalsoactsasa“shockabsorber”absorbingtheoverloadvoltagetostabilizealternatorvoltageoutput.Itisusedtosupplycurrentforstartingthecar.Uponstarting,thegeneratorwillrechargethebattery.AutomobileElectricalSystemText

StartingSystemTheelectromagnaticswitchofthestartingsystemisusedtocontrolthestartingcircuittomakeitswitchofforon.Theswitchcanbeasfollowing:1.Relaywhichusestheelectromagneticfieldofacoiltoattractanarmatureandclosethecontactpoints.2.Solenoidwhichusestheelectromagneticfieldofacoiltopullaplungerintothecoilandclosethecontactpoints.AutomobileElectricalSystemText

StartingSystemThestartermotordrawsagreatdealofelectricalcurrentfromthebattery.Alargestartermotormightrequire300to400amperesofcurrent.Thiscurrentflowsthroughtheheavy-gaugecableswhichconnectthebatterytothestarter.Thedrivercontrolstheflowofthiscurrentbyusingthestartingswitch.However,ifthewireswereroutedfromthebatterytothestartingswitchandthenontothestartermotor,thevoltagedropcausedbyresistanceinthewireswouldbetoogreat.Toavoidthisproblem,thesystemisdesignedwithtwoconnectedcircuits:thestatercircuitandthecontrolcircuit.AutomobileElectricalSystemText

StartingSystemThestartermotorconvertselectricalenergyfromthebatteryintomechanicalenergytoturntheengine.Itdoesthisthroughtheinteractionofmagneticfields.Whencurrentflowsthroughstatorwinding,amagneticfieldisformedaroundtheconductor.Alargequantityofcurrentgoesthroughthestarterrotorandgeneratesenoughtorquetoturntheenginecrankshaft.AutomobileElectricalSystemText

ChargingSystemThechargingsystemusestherotationoftheenginetocreateelectricity.Theelectricityrechargesthebatteryandprovidespowertooperatethevariousvehicleelectricalsystems.ThemodernchargingsystemconsistsoftheACgeneratorandvoltageregulator.TheACalternator(Fig.5-4),knownasgenerator,isabelt-drivenelectromagneticdivice,whichconvertstheengine'smechanicalenergyintoelectricalenergyandrechargesthebattery.Aftertheengineisstarted,thealternatorproduceselectricitytomeettheneedsofthevehicleandtokeepthebatterycharged.Thisistheprimaryjobofthealternator.AutomobileElectricalSystemText

ChargingSystem

AutomobileElectricalSystemFig.5-4ACAlternatorText

ChargingSystemInordertoreducethealternatoroutputvoltage,avoltageregulator(Fig.5-5)mustbeused.Itcontrolstheoutputvoltageofgeneratorbyadjustingthesizeofthegeneratorexcitationcurrent.Thiscontrolsthestrengthbyreadingvoltageoutputfromthealternator.Iftheoutputvoltagebecomestoohigh,theregulatorreducesfieldstrength.Iftheoutputvoltagedrops,theregulatorincreasesfieldstrength.Moreover,theregulatorcanbemainlydevidedintotwokinds:theelectromechanicalvoltageregulatorandtheelectronicvoltageregulator.AutomobileElectricalSystemText

ChargingSystem

AutomobileElectricalSystemFig.5-5VoltageRegulatorText

ChargingSystemOldervoltageregulatorsusecontactpointsthatareoperatedbyelectromagneticcoils.Theywerecalledelectromechanicalvoltageregulators.However,allvehiclesmadewithinthelast15yearsuseanelectronicregulator.Theelectronicvoltageregulatorusespowertransistors,integratedcircuits,diodes,andothersolidstatepartstocontrolalternatoroutputvoltage.Itcanavoidcontactstuck,rustorwear,withhighregulationaccuracyandlonglife,lightinweightandarewidelyusedtoday.AutomobileElectricalSystemText

IgnitionSystemThepurposeoftheignitionsystem(Fig.5-6)istoprovideanelectricsparktothecorrectcylinderattherighttimetoignitethefuel-airmixture.Mixedgasburnsandproducestremendousenergy,promotesdownwardmotionofthepistonandrotatestheenginecrankshaft.Theignitionsystemhastwotaskstoperform.First,itmustcreateavoltagehighenough(20,000V)toarcacrossthegapofasparkplug,thuscreatingasparkstrongenoughtoignitethefuel-airmixtureforcombustion.Second,itmustcontrolthetimingofthesparksothatitoccursattheexactrighttimeandignitedcombustiblemixtureaccordingtothefiringorderincylinder.AutomobileElectricalSystemText

IgnitionSystem

AutomobileElectricalSystemFig.5-6IgnitionSystemText

IgnitionSystemTheignitionsystemisdividedintotwosections：theprimarycircuitandthesecondarycircuit.Theprimarycircuit,thelow-voltagesideofthesystemcontrolsthesecondarycircuit,whichisthehigh-voltagesideofthesystem.Thefollowingarethebasicpartsoftheprimaryignitioncircuit:1.Batteryandalternator.Theysupplythelowvoltage(12V)usedtooperatetheprimarycircuit.2.Ignitionswitch.Key-operatedswitchisusedtofeedbatteryvoltagetotheprimarycircuit.3.Primarywires.Low-voltagewiresareusedtoconnecttheelectricalcomponentsoftheprimarycircuit.AutomobileElectricalSystemText

IgnitionSystem4.Ignitioncoilprimarywinding.Currentflowthroughthecoilproducesanelectromagneticfield,whichisusedtoinduceahighvoltageinthesecondarycoil.5.Breakerpoint.Itisusedtoopenandclosetheprimarycircuit.Thefollowingarethebasicpartsofasecondaryignitioncircuit:1.Ignitioncoilsecondarywinding.Ithasahighvoltage(40,000Vormore)inducediniteachtimetheprimarymagneticfieldcollapses.2.Coilwire.Itisaheavilyinsulatedwirethatfeedshighvoltagefromtheignitioncoiltodistributorcap.3.Distributorrotor.Itoperatesinconjunctionwiththedistributorcaptodistributethehighvoltagefromtheignitioncoiltotheindividualsparkplugwiresinthefiringorder.AutomobileElectricalSystemText

IgnitionSystem4.Distributorcap.Itisaninsulatedcapthattransfershighvoltagefromthedistributorrotortosparkplugwires.5.Sparkplugwire.Itisaheavilyinsulatedwirethatcarrieshighvoltagefromthedistributortothesparkplugs.6.Sparkplug.Itprovidestheairgapwithinthecombustionchamberforthehighvoltagetoarcacross,thusignitingthefuel-airmixture.AutomobileElectricalSystemText

IgnitionSystemAtpresent,therearethreedistincttypesofignitionsystems.Themechanical(conventional)ignitionsystemwasusedpriorto1975.Itwasmechanicalandelectricalandusednoelectronics.Theelectronicignitionsystemstartedfindingitswaytovehiclesproducedduringthemid-1970s.Theninordertoimprovetheignitioncontrolandreliability,andreduceengineemissions,tothemid-1980swithoutdistributorignitionsystemstartsapplyingtoautomobile.Thissystemwasalwayscomputorcontrolledandcontainednomovingparts,soreliabilitywasgreatlyimproved.AutomobileElectricalSystemText

AccessorySystemItisuniversallyknownthattheelectricalsystemsupplieslightinganddrivingpowerfortheautomobile.Therefore,lighting,horns,instrumentalpanelandwarningsystemsareincludedintheaccessorysystem.Herewewillattachgreatsignificancetothelightingsystemandwarningdevices.Thelightingsystemcomprisesofvariouslightingandsignalingdevicesorcomponentsfixedtothefront,sidesandrearofthevehicle,whichhasmultipleusesandfunctions.Firstandforemost,itprovidesilluminationforthedriverofavehicletodrivesafelyindark.Secondly,automobilelightsenhancethevisibilityofanautomobile.Atlast,automobilelightsactasthewarningsignals.Theyshowcaseinformationaboutthepresence,position,size,speedanddirectionofanautomobile.What'smore,auxiliarylights,headlights,taillights,sidelights,interiorlight,lightaccessoriesarecomponentsoftheautomobilelightingsystem.AutomobileElectricalSystemText

AccessorySystemAwarningdeviceisanalarmsystemremindingthedriverafuturedanger.Itspurposeistoremindthedriverofthewarningsystemtoprepareforthedangerandactaccordinglytomitigateagainstoravoidit.Thevehiclewarningsystemfurthercomprisesawarningunitwhichcontainsareceiver,asoundgenerator,andwarninglights.Whenadriverisfacedwithapotentiallydangeroussituationandinstinctivelygripsthesteeringwheelharder,thiscausesthevehiclewarningsystemtotransmitsignalstothereceiverinthewarningunitoftheinitiatingvehicleaswellasthereceiversinthewarningunitsofothervehicleswithinapredetermineddistance.Thetransmittedsignalcausesthewarninglighttoflashandgivethewarningsound，whichisgeneratedfromthewarningunitineachofthevehiclesreceivingthetransmittedsignal.AutomobileElectricalSystemText

AccessorySystemInshort,inrecentyears,automotiveelectricalsystemhaschangedalot.Variousauxiliaryelectricaldevicesareusedinmoderncars,suchasair-conditioningsystem,phones,televisions,radios,CDandDVDplayerswithsurroundingsoundsystem,electricdoorlocksandsoon.AutomobileElectricalSystem參考譯文電氣系統(tǒng)是汽車最主要的部分之一。它可以發(fā)電、蓄電，并為汽車電氣設(shè)備提供所需電能。電氣設(shè)備由電源和用電設(shè)備兩大部分組成。前者包括蓄電池和發(fā)電機(jī)，后者包括發(fā)動(dòng)機(jī)的起動(dòng)系統(tǒng)、汽油機(jī)的點(diǎn)火系統(tǒng)和其他用電裝置。因而，汽車電氣系統(tǒng)可以分為四大主要組成部分：起動(dòng)系統(tǒng)、充電系統(tǒng)、點(diǎn)火系統(tǒng)和輔助系統(tǒng)。起動(dòng)系統(tǒng)汽車的起動(dòng)系統(tǒng)（圖5-1）用于轉(zhuǎn)動(dòng)發(fā)動(dòng)機(jī)曲軸直到發(fā)動(dòng)機(jī)能依靠自身動(dòng)力進(jìn)行工作。為了做到這一點(diǎn)，起動(dòng)機(jī)必須從蓄電池得到足夠的電能。起動(dòng)機(jī)從蓄電池得到電能，再將這部分電能轉(zhuǎn)化成機(jī)械能通過驅(qū)動(dòng)機(jī)構(gòu)傳到發(fā)動(dòng)機(jī)曲軸飛輪上。汽車電氣系統(tǒng)參考譯文起動(dòng)系統(tǒng)

汽車電氣系統(tǒng)圖5-1起動(dòng)系統(tǒng)參考譯文起動(dòng)系統(tǒng)一般的起動(dòng)系統(tǒng)具體以下5個(gè)基本部件和兩套不同的電路，這些部件是：1.蓄電池（圖5-2）；2.蓄電池導(dǎo)線；3.起動(dòng)開關(guān)；4.起動(dòng)機(jī)（圖5-3）；5.電磁開關(guān)。汽車電氣系統(tǒng)圖5-2蓄電池圖5-3起動(dòng)機(jī)參考譯文起動(dòng)系統(tǒng)蓄電池是一種電化學(xué)設(shè)備。汽車使用的蓄電池的電壓為12V。蓄電池為交流發(fā)電機(jī)最初的勵(lì)磁提供電流。在充電時(shí)，蓄電池將發(fā)電機(jī)輸出的電能轉(zhuǎn)化為化學(xué)能儲(chǔ)存在蓄電池中。當(dāng)過載時(shí)，蓄電池與發(fā)電機(jī)共同為車輛提供電能。蓄電池還起到“減振器”（吸收過載電壓）的作用，使發(fā)電機(jī)的輸出電壓穩(wěn)定。蓄電池只為汽車起動(dòng)提供電能，起動(dòng)后發(fā)電機(jī)就為蓄電池充電。起動(dòng)系統(tǒng)的電磁開關(guān)用于控制起動(dòng)電路斷開或接通。開關(guān)形式如下：1.繼電器：利用線圈產(chǎn)生磁場(chǎng)吸引銜鐵并閉合觸點(diǎn)。2.電磁線圈：利用線圈產(chǎn)生磁場(chǎng)拉動(dòng)柱塞進(jìn)入線圈并閉合觸點(diǎn)。起動(dòng)機(jī)需要蓄電池提供強(qiáng)大的電流。一臺(tái)大型的起動(dòng)機(jī)需要300~400A的電流。電流通過大容量電纜，將蓄電池連接到起動(dòng)機(jī)上。駕駛員通過起動(dòng)開關(guān)來控制起動(dòng)電流。但如果用導(dǎo)線將蓄電池電流通過起動(dòng)開關(guān)直接連接到起動(dòng)機(jī)上，那么在導(dǎo)線上產(chǎn)生的電壓降就會(huì)過大。為了避免這種情況，起動(dòng)系統(tǒng)就設(shè)計(jì)了兩套電路：起動(dòng)電路與控制電路。汽車電氣系統(tǒng)參考譯文起動(dòng)系統(tǒng)起動(dòng)機(jī)將蓄電池的電能轉(zhuǎn)化為發(fā)動(dòng)機(jī)起動(dòng)的機(jī)械能。它是利用電磁互感的原理制成的。當(dāng)電流通過定子繞組，在其周圍就會(huì)產(chǎn)生磁場(chǎng)。大量電流通過起動(dòng)機(jī)的轉(zhuǎn)子，就會(huì)產(chǎn)生足以讓發(fā)動(dòng)機(jī)曲軸轉(zhuǎn)動(dòng)的力矩。

充電系統(tǒng)充電系統(tǒng)通過發(fā)動(dòng)機(jī)的轉(zhuǎn)動(dòng)來發(fā)電。所發(fā)的電用來為蓄電池充電并為各種電氣設(shè)備的運(yùn)行提供電能?，F(xiàn)代充電系統(tǒng)包含交流發(fā)電機(jī)和電壓調(diào)節(jié)器。交流發(fā)電機(jī)（如圖5-4所示），簡(jiǎn)稱為發(fā)電機(jī)，是一個(gè)用皮帶傳動(dòng)的電磁裝置，它將發(fā)動(dòng)機(jī)的機(jī)械能轉(zhuǎn)化為電能為蓄電池充電。當(dāng)發(fā)動(dòng)機(jī)起動(dòng)，發(fā)電機(jī)就發(fā)電來滿足車輛的行駛需要并保持為蓄電池充電。這就是發(fā)電機(jī)的主要工作。汽車電氣系統(tǒng)參考譯文

充電系統(tǒng)

汽車電氣系統(tǒng)圖5-4交流發(fā)電機(jī)參考譯文

充電系統(tǒng)為了降低發(fā)電機(jī)的輸出電壓，就需要用到電壓調(diào)節(jié)器（圖5-5）。它通過調(diào)節(jié)發(fā)電機(jī)勵(lì)磁電流的大小來控制發(fā)電機(jī)的輸出電壓。如果輸出電壓過高，調(diào)節(jié)器就減小勵(lì)磁電流。如果輸出電壓過低，調(diào)節(jié)器就增加磁場(chǎng)強(qiáng)度。此外，調(diào)節(jié)器主要分為兩種：電磁電壓調(diào)節(jié)器和電子電壓調(diào)節(jié)器。汽車電氣系統(tǒng)圖5-5電壓調(diào)節(jié)器參考譯文

充電系統(tǒng)老式電壓調(diào)節(jié)器是利用電磁線圈來控制的觸點(diǎn)式電壓調(diào)節(jié)器，它們被稱為電磁電壓調(diào)節(jié)器。但是，最近15年制造的汽車上使用的都是電子電壓調(diào)節(jié)器。電子電壓調(diào)節(jié)器通過控制晶體三極管、集成電路、二極管和其他固體部件來控制發(fā)電機(jī)的輸出電壓。它能避免觸點(diǎn)卡住、生銹或磨損；調(diào)節(jié)精度高、重量輕、壽命長(zhǎng)，因而被廣泛使用。汽車電氣系統(tǒng)參考譯文

點(diǎn)火系統(tǒng)點(diǎn)火系統(tǒng)（圖5-6）的作用是在適當(dāng)?shù)臅r(shí)刻把電火花提供給汽缸，點(diǎn)燃空氣燃油混合氣。混合氣燃燒能產(chǎn)生巨大能量，推動(dòng)活塞向下運(yùn)動(dòng)并帶動(dòng)曲軸旋轉(zhuǎn)。點(diǎn)火系統(tǒng)要滿足兩個(gè)基本要求：首先，點(diǎn)火系統(tǒng)必須產(chǎn)生足夠高（20000V以上）的點(diǎn)火電壓擊穿火花塞間隙，從而使火花塞處的電火花強(qiáng)勁有力去點(diǎn)燃混合氣體；其次，它必須控制點(diǎn)火時(shí)機(jī)，使其發(fā)生在恰當(dāng)?shù)臅r(shí)候，并按汽缸的點(diǎn)火順序點(diǎn)燃可燃混合氣。汽車電氣系統(tǒng)圖5-6點(diǎn)火系統(tǒng)參考譯文

點(diǎn)火系統(tǒng)點(diǎn)火系統(tǒng)分為兩條回路：初級(jí)和次級(jí)。初級(jí)回路是系統(tǒng)的低壓端，并控制著次級(jí)回路，而次級(jí)回路是系統(tǒng)的高壓端。以下是初級(jí)回路的基本組成部分：1.蓄電池和發(fā)電機(jī)。它們提供低電壓（12V）讓低壓電路正常工作。2.點(diǎn)火開關(guān)。通過點(diǎn)火開關(guān)的控制，將蓄電池電壓提供給初級(jí)電路。3.初級(jí)導(dǎo)線。初級(jí)導(dǎo)線為低壓導(dǎo)線，用來連接初級(jí)回路的各個(gè)部件。4.點(diǎn)火線圈初級(jí)繞組。電流通過線圈時(shí)產(chǎn)生一個(gè)電磁場(chǎng)，用來在次級(jí)線圈中產(chǎn)生高電壓。5.斷電器觸點(diǎn)。用來斷開或接通初級(jí)電路。汽車電氣系統(tǒng)參考譯文

點(diǎn)火系統(tǒng)以下是次級(jí)回路的基本組成部分：1.點(diǎn)火線圈次級(jí)繞組。當(dāng)初級(jí)回路的電磁場(chǎng)消失時(shí)，產(chǎn)生一個(gè)高電壓（40000V或更高）。2.中央高壓線。采用絕緣性能很好的導(dǎo)線。將高電壓從點(diǎn)火線圈分配到需要點(diǎn)火的火花塞導(dǎo)線上。3.分電器分火頭。它的作用是與分電器蓋相連，將高電壓從點(diǎn)火線圈分配到需要點(diǎn)火的火花塞導(dǎo)線上。4.分電器蓋。此蓋為絕緣性的，確保高壓電從分火頭傳輸?shù)交鸹ㄈ麑?dǎo)線上。5.火花塞導(dǎo)線（分缸高壓線）。采用絕緣性能很好的導(dǎo)線，將高電壓從分電器傳輸?shù)交鸹ㄈ?.火花塞。在燃燒室里提供空氣間隙，確保高電壓形成電弧，從而點(diǎn)燃混合氣。汽車電氣系統(tǒng)參考譯文

輔助系統(tǒng)眾所周知，電氣系統(tǒng)還要為汽車輔助用電設(shè)備供電。輔助系統(tǒng)包括照明、喇叭、儀表盤和警告系統(tǒng)等。這部分將著重講解照明系和報(bào)警裝置。照明系統(tǒng)是一個(gè)包括了各種固定在汽車前部、側(cè)部和后部的用于照明和信號(hào)的裝置或部件，它具有多種用途和功能。首先，它為汽車駕駛員在夜間安全行車提供照明。其次，汽車車燈提高了汽車前進(jìn)時(shí)前方的能見度。最后，汽車車燈還能擔(dān)任警告信號(hào)。它們展示了汽車的存在、位置、大小、速度和方向等信息。其中，汽車照明系統(tǒng)包含輔助光、頭燈、尾燈、側(cè)記、室內(nèi)裝飾燈和光配件等零部件。汽車電氣系統(tǒng)參考譯文

輔助系統(tǒng)報(bào)警裝置是一種用于提醒駕駛員防范危險(xiǎn)的報(bào)警系統(tǒng)。它的作用是通過報(bào)警裝置提醒駕駛員對(duì)危險(xiǎn)提早做準(zhǔn)備并因此減緩或避免危險(xiǎn)帶來的傷害。汽車報(bào)警裝置包括一整套警告部件，主要有一個(gè)接收裝置，發(fā)聲器和警告燈。當(dāng)駕駛員面對(duì)一種潛在的危險(xiǎn)狀況時(shí)，他會(huì)本能地握緊轉(zhuǎn)向盤，這種反應(yīng)會(huì)導(dǎo)致汽車警告系統(tǒng)將信號(hào)傳遞給起動(dòng)的汽車的警告裝置的接收器，以及傳遞給在一定距離內(nèi)其他車輛的接收器。傳遞的信號(hào)轉(zhuǎn)變?yōu)閳?bào)警燈的閃爍并給予警告響聲，這些是由警告裝置接收到警告信號(hào)產(chǎn)生的反應(yīng)?？傊?，最近幾年，汽車電氣系統(tǒng)變化很大。在現(xiàn)代新型汽車中還使用了其他各種電氣輔助部件，如空調(diào)系統(tǒng)、電話、電視、收音機(jī)、帶有環(huán)繞聲音響的CD和DVD機(jī)、電控門鎖等。汽車電氣系統(tǒng)ReadingMaterialAlmosteveryautomobilemanufacturerisusedtotestingthesystem'soperationofthecarwhenitleavestheassemblyline.Specialautomotivediagnosticscannersareavailableforaccessinginformationfromcomputerizedvehiclesthroughconnectionstothisserialdatalink.Informationoninputsandoutputstothecomputer,suchasfaultcodes,coolanttemperature,RPM,timingretard/advance,vacuum,manifoldabsolutepressure,andoxygensensoroutputcanberetrievedusingthesedevices.Thesekindsofinformationcanbedisplayedonascreen,shownasadigitalreadout,orprintedonapieceofpaperandusedfortroubleshootingthesystem.

SystemDiagnosisReadingMaterialMostcomputerizedautomotivecontrolsystemsareequippedwithbuiltinself-diagnosticsystemswhichconductamultitudeoftestsofthesystem.Thebasicmicrocomputerself-diagnosissystemisdesignedtomonitortheinputandoutputsignalsofthesensorsandactuators,andtostoreanymalfunctionsinitsmemoryasatroublecode.Generally,checksaremadeforopen,shortcircuitsandillogicalsensorreadings.

SystemDiagnosisReadingMaterialTheelectroniccontrolsystemisbasicallycomposedofthecomputerorelectroniccontrolmodule,enginewiringh