Issuu

Isuzu Npr Nqr 2001 Electrical Troubeshooting-15i16489 Full download: http://manualplace.com/download/isuzu-npr-nqr-2001-electrical-troubeshooting-15i16489/ This is the cut pages sample. Download all 260 page(s) at: ManualPlace.com

ElectricalTroubleshootingManual

CircuitIndex Diesel Gas ... 2

Airconditioner 2-10 Blowercontrols .............. 60 ....... 60-1 ... 6

Compressorcontrols..........63 ....... 63-2

Anti-lockbrakesystem(ABS).....44 ....... 44-4 201

A/Tshiftindicator .............. 89 ....... 89-1 202 Automatictransmissioncontrols ... 39 ....... 39-4 .203 Backuplights ............... 112 ...... 112-1

Blowercontrols ................ 60 ....... 60-1

Brakelights................110-12.....110-13 Brakewarningsystem. .......... 71.......71-2

Ceramicheater................ 61

Chargingsystem...............22 ....... 22-2

Cigarettelighter. .............. 155 ....... 155

Compressorcontrols............63 ....... 63-2 Consolelights ................ 117......117-2

Corneringlights.............110-16 ..... 110-18 Dashlights .................. 117 ..... .117-2

Domelight................... 114 ....... 114

Enginecontrols................23 ........ 24 81-2

Enginecoolanttemperaturegauge .. 81 Enginestopsystem. ............ 26

Exhaustbrakesystem. .......... 25

2001 NPR/NQR

Contents

HowtoUseThisManual ........... Troubleshooting .................. Fuse/RelayInformation ............ CircuitSchematics(seeCircuitIndex) ComponentLocationPhotographs. HarnessConnectorViews.......... ConnectorandWireHarnessRouting.

Headlights...................

Heater.......................

Horns .......................

Ignitionsystem .................. Indicators ....................

Licenselight ................

Lightingswitchdetails...........

.......

Powerdistribution ..............

.......

Powerdoorlocks.............. 130 .......

Powerwindows...............120 ....... 120 Soundsystem................ 150 ....... 150 Speedometer ................. 33 .......

Startingsystem................ 21 .......

Taillights...................110-1......110-3 Turnlights ................. .110-6 .....

Vehiclespeedsensor(VSS)......

.......

Windshieldwiper/washer ........

........

Allinformationcontainedinthismanualisbasedonthelatestproductinformationavailableatthetimeofprinting.Wereservetherighttomakechangesatanytimewithoutnotice.Nopartof thispublicationmaybereproduced,storedina retrievalsystem,ortransmitted,inanyformbyanymeans,electronic,mechanical,photocopying,recording,orotherwise,withoutpriorwritten permissionofthepublisher.Thisincludestext,figuresandtables. ©2000AMERICANISUZUMOTORSINC. PrintedinU.S.A.

Frontparklights .............. 110 Fuelgauge ................... 81 Fuseboxdetails ............... 11 Gauges...................... 81 Grounddistribution ............. 14 .110-2 ..81-2 ..11-4 ..81-2 .14-4 .110-8 .100-2 .60-1 40 20 80-3 Hazardlights................110-6

100

110-1

12-3

10-4

130

33-1

21-2

.110-8

33-1

HOWTOUSETHISMANUAL

TroubleshootingInformation

Thismanualcontainsthefollowingtroubleshooting information:

• FuseInformation

• CircuitDetails

ElectricalCircuitSchematic

ComponentLocationIndex

CircuitOperation QuickChecks(ifrequired)

Troubleshooting(ifrequired)

• ComponentLocationPhotographs

• HarnessConnectorFaces

HarnessRoutingViews

TheElectricalCircuitSchematicshouldalwaysbe yourstartingpointinusingthisElectricalTroubleshoot¬ ingManual.Theschematicshowstheelectricalcurrent pathswhena circuitisoperatingproperly.Itisessential tounderstandhowa circuits/iou/dworkbeforetryingto figureoutwhyitdoesn't.Schematicsareshownwith thestarterswitch intheOFFpositionandother switchesintheoffor"atrest"position.

TheComponentLocationIndexhelpsyoufindwhere thepartsofa circuitarelocatedin a vehicle.Abrief statementofthelocationisgivenandalsoa reference to a photographthatshowsthecomponent.These ComponentLocationPhotographsareinsection201. Theindexalsoliststhenumberofcavitieswithineach connectorandtheconnectorcolor.Notallcavitieswill havewires.

TheCircuitOperationwillhelpyoutounderstandthe circuit.Itdescribesthecomponentsandhowthecircuit works.

PageNumbering

Thismanualisorganizedintosectionswithmostsec¬ tionscontainingcircuitdetails.Eachsectionhas a uniquenumberthatwillnormallyremainthesame, yearafteryear.Forexample,theheadlightscircuitwill besection100withthefirstpageofthesectionnum¬ bered100.Thefollowingpagesofthissectionwillbe numbered100-1,100-2,and100-3.

Symbols Entire component shown Normallyopen switch |— I Onlypartofcomponent shown;remainder I shownelsewhere Multi-positionswitch Componentname Gangedswitch contacts Dashedlineshows mechanicalconnection Fuse X/S X^N Relay,shownwithnocurrentthrough relaycoil;whencurrentflowsthrough coil,contactarmchangesposition x^ x^ HOTATALLTIMES mF-5^ ) ECU(BAT) 1T1IDA ,^^ 01IUW3VUlLClyC15pICOCI11 "^withtheignitioninRUN ^~~~~~—Identification ^^~~~~—Currentrating ^/ Coil Circuit Breaker ~V~l Solenoid Fusiblelinkconnectedtoscrew terminal(shownseparated) Solenoid Valve 0-,- Fusible Link Horn Indicatorlight; illuminatesa symbolorword(s) ^ Speaker

Symbols

Wavylinemeansthewireis -^ brokenbythebindingofthebook butcontinuesonthenextpage

Capacitor

Arrowmeanswireconnectsto anothercircuit;showsdirection ofcurrentflow Motor Brush

Circuitiscontinuedwhereindicated; arrowshowsdirectionofcurrentflow andisrepeatedwherecircuitcontinues

Diode;positive currentflowsin arrowdirection

HOWTOUSETHISMANUAL

(cont'd) Resistor Variable resistor

BLK...... BLU...... BRN .....CLR .....GRN .....GRY ..... LTBLU ... LTGRN... ORN .....PNK .....RED ..... VIO...... WHT..... YEL...... ....... black ........ blue ...... brown ....... clear ...... .green ........gray .... lightblue ... lightgreen ..... .orange ....... .pink ........ red ....... violet ....... white ...... yellow Wireand connectorcolors Potentiometer

2-2

Splice

linemeanscircuitis

showncomplete

complete whereindicated A/T T A M;T T

options 1<+^ 1<±^Componentcase groundedtocar RFI(RadioFrequencyInterference) shieldingarounda wire;theshielding isalwaysconnectedtoground -J-9 Female terminal Male terminal Wireattachedto carforground 1 Connector -J-9 ^J-128 Twoterminalsinsame connector;dashedline showsphysicalconnection Wireindirectlyconnected toground;mayhaveone ormoresplicesinline AB-1 /\ -71\- B-272 Junctionblock connector y» Dashedlinemeanscircuit

butis complete

indicated i 21B-85 |— ")Connectoron i componentI lead(pigtail) L-r Connector attachedto component

Dashed

not

butis

Choicebracket; showsdifferencesin wiringfor

notshowncomplete

where

CircuitSchematics

Circuitschematicsbreaktheentireelectricalsystem intoindividualcircuits.Electricalcomponentsthat worktogetherareshowntogether.

Eachdrawingisarrangedsothatcurrentflows frompositiveatthetopofthepage,toground,at thebottomofthepage.The"hot"labelsatthetopof a fuseshowwhenthestarterswitchsuppliespowerto thatfuse.

Wiresthatconnecttoanothercircuitareshownwithan arrowheadpointinginthedirectionofcurrentflow.The nameofthecircuitthatshareswiringisprovidedforref¬ erence.

"SeeFuseBoxDetails"meansthatthereareothercon¬ nectionstocircuitsthatarenotshown.Theseshared circuitsareshownontheFuseBoxDetailscircuitsche¬ matic."SeeGroundDistribution"meansthatthereare sharedgroundcircuitswhichareshownontheGround Distributioncircuitschematic.

Noattemptismadeontheschematictorepresent componentsandwiringastheyphysicallyappearon thecar.Forexample, a 4-footlengthofwireisnot treatedanydifferentlyina schematicthanonewhichis onlyafewincheslong.Thenumberofcavitiesforeach connectorislistedintheComponentLocationIndex ratherthanbeingillustrated.Similarly,switchesand othercomponentsareshownassimplyaspossible withregardtofunctiononly.

Theexampleonthispageshowsa hornsschematic. LocatethehornschematicbyusingtheCircuitIndex. Thecircuitschematicwilllooksimilartotheoneshown below.Theschematicisreadfromtoptobottom.

Voltageisappliedtothehornrelayatalltimes.When therelaycoilisgroundedbyclosingthehornswitch, therelaycontactsclose.Whentherelaycontactsare closed,boththeLHandRHhornsareenergized.

HOWTOUSETHISMANUAL

GR r~ 1 GRN/RED 3; GRN/RED BLK| ^ N 2, \ \.\^~~~ ;B-70 1 GRN | | AB-24 —————————-^,^ Horn Switch | HOTATALLTIMES | ra GRN GRN/WHT 3; GRNfWHT Steering Wheel GRNfWHT 1< 1—a r ^ F-18 HAZAR 20A ^ —— GRNJ SRN SeeFuse i ;H-5 L »-' jFuse |BOX D.HORN1 Page11-1(Diese Page11-5(Gas) "ICab |Relay or" 'Box Relay GRNW ,-i Right \ Hand ——\ Horn 4 1AJ 1 M.' -5 ^\ Left \ Hand ——-\ Horn 2-4

PowerDistribution

ThePowerDistributionschematicshowsthewiring fromthebatteryandgeneratortothestartersolenoid, relaybox,fusebox,starterswitchandlightswitch.The firstcomponentaftera fusiblelinkisalsoshown.Incer¬ taininstances,thefirstcomponentafterafuseboxfuse andlightswitchisalsoshown.

ThePowerDistributionschematicreferstoFuseBox DetailsandLightingSwitchDetailsschematics.By usingthesethree(3)schematics,powerdistribution wiringcanbefollowedfromthebatteryandgenerator tothefirstcomponentaftera fusiblelink,fuse,andlight switch.Theabilitytofollowthepowerdistributionwiring tothefirstcomponentineachcircuitisextremelyhelp¬ fulinlocatingshortcircuitswhichcausefusiblelinks andfusestoopen.

Thefusesintheschematicbeloware"HotAtAll Times,"sincebatteryvoltageisalwaysappliedtothem.

BL B KfRE K/Y V °r M F ^ EL! WHT 1 r Heater-A Relay Page60 and63 1 J-998 A.P-5 Frame) (Engi WHT ^ BLK ^i—— 1 B-21 -1 1 l i(C "^ ^ —— ^Up u K/YEL 2 HeadlightRelay Exhaust Page100and1)0-10 BrakeRelay Pages21,25 and25-4 Batteries 4 Wh WH 11B-20 ^ /"^ BLU ] i L ne) —• T | I 1-^1 1 -1 WHT 1 r" i Starter Solenoid '1——————————————NWHT B-38 -1 i I r i ^ -1 ^ rx70^ iBox 1 / MAIN ^ pa8e10-2 | | ) 80A |Starter 1 i | .Page21 WHT| WHT | Qi"2 WHT 1 -1 Generator 2? Page21 WHT Cab Relay I i T i |DU« Box | rt-|F-8 r-|F-7 d-jF-6 d-|F-5 ( 1 .) STOP D™1- ) DOME \\ ECU(BAT) 1 LlJLIGHT LlJLIGHT LLJLIGHT LUIOA 1 | 10A 10A IOA | SeeFuse SeeFuse SeeFuse SeeFuse BoxDetails, BoxDetails, BoxDetails, BoxDetails, Page11 Page11 Paged Paged (cont'd) ;H-6 WHT —————————————s -1Fuse 2-5

CircuitSchematics(cont'd)

FuseBoxDetails

TheFuseBoxDetailsschematicshowsallofthewiring betweena fuseandthecomponentsconnectedtothat fuse.TheFuseBoxDetailsschematicishelpfulin locatinga shortcircuitthatcausesa fusetoopen.This schematicmayaidintroubleshootinganinoperative circuitbyshowinga secondcircuitthatusesthesame fuse.Ifthesecondcircuitworks,thenthefuseandcer¬ tainwiresoftheinoperativecircuitaregood.

HOWTOUSETHISMANUAL

LightingSwitchDetails

TheLightingSwitchDetails

Lighting

locatinga shortcircuit

relays. GRN/B 1~ 1—GRN/OR GRN/OR 1~ '1 '| Off" h | [ Headlights>— L BLK L BLK ^ ~T J. ^ N 8^ N ,ug —/ ISw -^"Head 1 [Park | T -1 1 | .t GRN/BLK | [ ?B-70 SeeGround Distribution Page14 .-^ B-7 GRN ^ LTGR 1Combination iting Switch tch | LTG HOTATALLTIMES | BLK | Jf-22 T jYB-2 WIRED | WIRED 1 r i Illumin Contr Page 'Fuse F-7 |Box TAILLIGHT 10A 1 GRN/BLK See ^ Box / B-1 ation Her 17 .Cab Taillight ^1 Relay 1Box 2 | LTGRN/RED 4? GRN/WHT r [^ I LeftF J Comb Light Asseir Page '•use Details ay LTGRN/RED ;B-5 0 ^: ", ont nation I i biy Radio 10-1 Page i » --!-<; ' LTGRN/ 1 RED 1 2^ LTGRN/ RED ' 1; | RED , r B-28 1 -11 l 1 0;DO 1 SWIT - -' I Page l andl ^ - -A/T;H-12 ' I ;N-1 | 1 1 1 • -J 1 FF CH l 39-2 , 7 (cont'd) 2-7

schematicshowsallthe wiringbetweenthelightswitch,lightrelays,andthe componentsconnectedtotheoutputofthelightswitch andrelays.The

SwitchDetailsschematicis helpfulin

ontheoutputsideof thelightswitchand

CircuitSchematics

GroundDistribution

(cont'd)

TheGroundDistributionschematicsshowwhichcom¬ ponentsshare a groundpoint.Thisinformationcan oftenbea time-saverwhentroubleshootinggroundcir¬ cuits.Forexample,intheschematicbelow,ifboth headlightsandthepark/turnlightononesideareall out,youcouldsuspectanopenintheircommon groundwireorthegroundconnectionitself.Onthe otherhand,ifoneofthelightsworks,youknowthatthe groundandthewireuptothesplicearegood.You havelearnedthisjustbyinspectingtheschematicand knowingthevehicle'ssymptoms.Noactualworkonthe lightingsystemisneeded.

HOWTOUSETHISMANUAL

,. LeftTailLightAssembly RightTailLightAssembly „""" Pages110-t,110-7,110-12and110-17 Pages110-1,110-7,110-12and110-17 •lale r -i r -i Light Tall Stop Turn Back-up 1 Tail Stop Turn Back-up ^-i :©0®! !(^)®®! OOl i Y 1 T T1 "-R-2 6? Engine ABS Stop Hydro Motor Unit Page26 Page44-2 r- -i i- -i 11 11 1 1Aj-9 Aj-999 J 1. 'J-34 16s 16^ / 1 J 'J-79A ?J-79 a^ - withH.B.B, i- M/Tf Y l i Y } l i ;R-1 6', H.B.B. 1 Q.I i Condenser 1 Level i Fan Sensor W3-2 ' Page71 l r" ~1 l <~ -l l 1 1 , 1 1 i L J i '-1^ i ' 1 ' 2AJ-51A YEL/BLU | Y ;H-16 1 2^J-128 i 2^J-51 1 ' T r Y i ^R-6 1 l ExhaustBrake ^1 MAGValve swltl;h ' Pages25-2and25-6 Page25-5 , , i- -i 1 1 ' } \ Li i l— J r 2N RED | ' I^E-H1 10^H-14I T ' 'J-31 ---S 2-8

Acomponentlocationindexfollowseachschematic. Exceptforthelocationofobviouscomponentslikeleft headlight,theindexliststhelocationofeverycompo¬ nent,connectorandgroundintheschematic.The indexalsogivesreferencestocomponentlocationpho¬ tographslocatedinsection201.Thenumberofcavities ineachconnectorandtheconnectorcolorisalso listed.Wiresmaynotbeusedinallconnectorcavities.

ComponentLocation

ComponentLocationIndex (RefertoSection201forphotographs.) Component FuseBox..................Leftsideofdash,behindpanel................. LeftHorn.................. Leftsideofenginecompartment,belowheadlight. RightHorn ................ Rightsideofenginecompartment,belowheadlight. PhotoNo. ....... 81 ....... 15 ....... 17 Connector B-2(13-WHT)..............Underleftsideofdash,aboveleftsideofsteeringcolumn ................ 71 H-41(16-GRN).............Underleftsideofdash,atkickpanel ................................. 63 Ground C-39 ..................... Rightrearcornerofenginecompartment..............................42 2-9

HOWTOUSETHISMANUAL

Five-StepTroubleshooting

Thefollowingfive-steptroubleshootingprocedureis recommended:

1. VerifytheProblem

Checktheproblemcircuit'soperationtobesureyou understandwhat'swrong.Donotbegindisassemblyor testinguntilyouhavenarroweddownthepossible causes.

Ifthesystemyouaretroubleshootinghasa built-inselfdiagnosticsystem,refertotheappropriatesectionof theServiceManual.

2. AnalyzetheCircuitSchematic

Analyzetheschematic.ReadtheCircuitOperationtext ifyoudonotunderstandhowthecircuitshouldwork. Checkcircuitsthatsharethewiringwiththeproblem circuit.Thenamesofcircuitsthatsharethesamefuse, ground,switch,etc.,areincludedoneachelectrical schematic.SharedcircuitsarealsoshownonPower Distribution,GroundDistribution,DashFuseBox,and LightingSwitchDetailspages.Trytooperatethe sharedcircuits.Ifthesecircuitswork,thentheshared wiringisOK.Thecausemustbewithinthewiringused onlybytheproblemcircuit.Ifseveralcircuitsfailatthe sametime,chancesarethepower(fuse)orgroundcir¬ cuitisfaulty.

3. FindtheCause

• narrowdownthepossiblecauses

• usethetroubleshootinghints

• makethenecessarymeasurementsasgivenin thetroubleshootingprocedures

• beforeyoureplacea component,checkpower, signal,andgroundwiresatthecomponenthar¬ nessconnector

4. RepairtheProblem

Oncethespecificproblemisidentified,maketherepair. Besuretousepropertoolsandalwaysobservesafe procedures.

5. ChecktheRepair

Checktherepairedcircuit'soperationinallmodesto makesurethatyou'vefixedtheentireproblem.Ifthe problemwasa blownfuse,testallcircuitsonthatfuse. Makesurethatnonewproblemsturnup.

TestEquipment

VoltmeterandTestLight

Usea voltmeterortestlighttocheckforvoltage.While a testlightshowswhetherornotvoltageispresent, a voltmeterindicateshowmuchvoltagethereis.

CAUTION:Anumberofcircuitsincludesolidstate devices.Voltagesinthesecircuitsshouldbetested onlywith a 10-megaohmorhigherimpedance digitalmultimeter.Neverusea testlightoncircuits thatcontainsolid-statedevices.Damagetothe devicemayresult.

Oncircuitswithoutsolid-statedevices, a testlightmay beusedtocheckforvoltage.Atestlightismadeupof a 12-voltbulbwith a pairofleadsattached.After groundingonelead,touchtheotherleadtovarious pointsalongthecircuitwherevoltageshouldbe present.Thebulbwillgoonifthevoltageatthepoint beingtestedisgreaterthan5volts.

Self-PoweredTestLightandOhmmeter

Usea self-poweredtestlightorohmmetertocheckfor continuity.Theohmmetershowshowmuchresistance thereisbetweentwopointsalonga circuit.Lowresis¬ tancemeansgoodcontinuity,

CAUTION:Neverusea self-poweredtestlighton circuitsthatcontainsolid-statedevices.Damageto thesedevicesmayresult.

Diodesandsolid-statedevicesina circuitcanmakean ohmmetergivea falsereading.Tofindoutifa compo¬ nentisaffectinga measurement,takeonereading, reversetheleads,andtake a secondreading.Ifthe readingsdiffer,thecomponentisaffectingthemea¬ surement.

Circuitsthatcontainsolid-statedevicesshouldonlybe testedwitha 10-megaohmorhigherimpedancedigital multimeter.

2-10

Aself-poweredtestlightconsistsofa lightbulb,battery andtwoleads.Iftheleadsaretouchedtogether,the bulbwillgoon.

Self-PoweredTestLight

Aself-poweredtestlightisonlyusedonanun-powered circuit.Firstdisconnectthebatteryorremovethefuse thatfeedsthecircuityouareworkingon.Selecttwo pointsalongthecircuitthroughwhichthereshould havecontinuity.Connectoneleadoftheself-powered testlighttoeachpoint.Ifthereiscontinuity,thetest light'scircuitwillbecompletedandthebulbwillgoon.

FusedJumperWire

Usea jumperwiretobypassanopencircuit.Ajumper wireismadeupofanin-linefuseholderconnectedtoa setoftestleads.Itshouldhavea fiveamperefuse. Neverusea jumperwireacrossanyload.Thisdirect batteryshortwillblowthefuse.

TroubleshootingTests

TestingForVoltage

Thistestmeasuresvoltageina circuit.Whentestingfor voltageata connector,youmaynothavetoseparate thetwohalvesoftheconnector.Instead,probethe connectorfromtheback.Alwayscheckbothsidesof theconnectorbecausedirtandcorrosionbetweenits contactsurfacescancauseelectricalproblems.

1. Connect one lead of test light to known good ground,orifyouareusinga voltmeter,besureyou connectitsnegativeleadtoground.

2. Connecttheotherleadofthetestlightorvoltmeter tothepointyouwanttocheck.

3. Ifthetestlightglows,thereisvoltagepresent.Ifyou areusinga voltmeter,notethevoltagereading.It shouldbewithinonevoltofmeasuredbatteryvolt¬ age.Alossofmorethanonevoltindicatesaproblem.

ShortFinder

Shortfindersareavailabletolocateshortstoground. Theshortfindercreatesa pulsingmagneticfieldinthe shortedcircuitandshowsyouthelocationoftheshort throughbodytrimorsheetmetal.Itsuseisexplainedin thefollowingtroubleshootingtests.

RED Switch ^, \ BLU ^—|Voltmeter \ -L^ or \ / TestLight Y Solenoid 2-11

HOWTOUSETHISMANUAL

TroubleshootingTests(cont'd)

TestingForContinuity

Thistestchecksforcontinuitywithina circuit.Whentest¬ ingforcontinuityata connector,youmaynothaveto separatethetwohalvesoftheconnector.Instead,probe theconnectorfromtheback.Alwayscheckbothsidesof theconnectorbecausedirtandcorrosionbetweencon¬ tactsurfacescancauseelectricalproblems.

1. Disconnectthenegativecablefromthecarbattery.

2. If you are using an ohmmeter, hold the leads togetherandadjusttheohmmetertoreadzero ohms.

3. Connectoneleadofself-poweredtestlightorohm¬ metertooneendofthepartofthecircuityouwish totest.

4. Connecttheotherleadtotheotherend.

5. Iftheself-poweredtestlightglows,thereiscontinu¬ ity.Ifyou'reusinganohmmeter,lowornoresis¬ tancemeansgoodcontinuity.

TestingForVoltageDrop

Thistestchecksforvoltagedropalong a wire,or througha connectionorswitch.

1. Connectthepositiveleadofa voltmetertotheend ofthewire(ortothesideoftheconnectororswitch) closesttothebattery.

2. Connectthenegativeleadtotheotherendofthe wire(ortheothersideoftheconnectororswitch).

3. Operatethecircuit.

4. Thevoltmeterwill showthedifference in voltage betweenthetwopoints.Adifference,ordropof morethan0.5voltsmayindicatea problem.Check thecircuitforlooseordirtyconnections.

2-12

TestingForAShortToGroundWithATestLightOr Voltmeter

1. Removetheblownfuseanddisconnecttheload.

2. Connecta testlightorvoltmeteracrossthefuseter¬ minals.Makesurevoltageisbeingappliedtothe batterysidefuseterminal.Checkschematictosee iftheignitionswitchneedstobeinRUN.

3. Beginningnearthefusebox,wiggletheharness. Continuethisatconvenientpointsaboutsixinches apartwhilewatchingthetestlightorvoltmeter.

4. Whenthetestlightblinksorthevoltmeterneedle moves,thereisa shorttogroundinthewiringnear thatpoint.

TestingForA ShortToGroundWithA SelfPoweredTestLightOrOhmmeter

1. Removetheblownfuseanddisconnectthebattery andload.

2. Connectoneleadof a self-poweredtestlightor ohmmetertothefuseterminalloadside.

3. Connecttheotherleadtoa knowngoodground.

4. Beginningnearthefusebox,wiggletheharness. Continuethisatconvenientpointsaboutsixinches apartwhilewatchingthetestlightorohmmeter.

5. Iftheself-poweredtestlightblinksortheohmmeter needlemoves,thereisa shorttogroundinthewir¬ ingnearthatpoint.

ihy.a SHORTTO '/K GROUND LOAD DISCONNECTED »y^ SHORTTO A^ GROUND LOAD DISCONNECTED 2-13

TroubleshootingTests(cont'd)

TestingForAShortToGroundWithAShortFinder

1. Withthebatteryconnected,removetheblownfuse.

2. Connecttheshortfinderbetweenthepositivebat¬ teryterminalandtheloadsidefuseterminal.

3. Closeallswitchesinserieswiththewirethatyou aretroubleshooting.

4. Turnontheshorttinder.Thiswillsendpulsesofcur¬ renttotheshortandcreatea pulsingmagneticfield aroundthewiringbetweenthefuseboxandthe short.

5. Beginningatthefusebox,slowlymovetheshort findermeteralongthecircuitwiring.Themeterwill showcurrentpulsesthroughsheetmetalandbody trim.Aslongasthemeterisbetweenthefuseand theshort,theneedlewillmovewitheachcurrent pulse.Onceyoumovethemeterpastthepointof theshort,theneedlewillstopmoving.Check aroundthisareatolocatethecauseoftheshort circuit.

HOWTOUSETHISMANUAL

2-14 '\|/'____ SHORTTO /K GROUND

ro 01

FUSE/RELAYINFORMATION RelayBox / ^ 1 o] r^ir^5i Q Q ^/ J-12 J-13 2 J-14 3 4 5 J-15 J-18 J-16 J-19 DDIDD J-17 J-20 DD I Fuse Number 1 2 3 4 5 F-21 F-22 FuseName MAIN KEY ABS(Gas) GLOW(Diesel) ABS(Diesel) C/HEATER(Diesel) CONDENSERFAN(Diesel) Amps 80A 50A 60A 60A 60A 15A CircuitProtected Powerdistribution Powerdistribution ABS(Gas),Enginecontrols(Diesel) ABS Ceramicheater Notused Condenserfan RelayNumber Relay RelayNumber Relay J-12 Starter J-16 Fuelpump(Gas) J-13 Glow-1(Diesel) J-17 Condenser(Diesel) J-14 C/Heater(DieselM/T) J-18 Exhaustbrakecontrol(Diesel) J-15 Warmcut1(Diesel) J-19 Enginewarmcut2(DieselA/T) A/Cenable(Gas) J-20 I.D.lightrelay 6

Isuzu Npr Nqr 2001 Electrical Troubeshooting-15i16489

Full download: http://manualplace.com/download/isuzu-npr-nqr-2001-electrical-troubeshooting-15i16489/

Fuse Number

F-1 F-2 F-3 F-4 F-5 F-6 F-7 F-8 F-9 F-10 F-11 F-12 F-13 F-14 F-15 F-16 F-17 F-18 F-19 F-20

HEATER

AIRCON

FuseName

EXHAUSTBRAKE(Diesel)

PCM(IGN)(Gas) D.R.L.(Diesel)

ENGINE(IGN)(Gas) ECU(BAT)(Diesel) A/TSOLENOID(GAS)

DOMELIGHT

TAILLIGHT STOPLIGHT HEADLIGHT(RH) HEADLIGHT(LH) WIPER,WASHER GENERATOR

TURNS/LIGHT

ECU(IGN)(Diesel)

PCM(ACC)(Gas)

AUDIO,CIGARLIGHTER

POWERSOURCE ENGINESTOP(Diesel)

FUELPUMP(Gas) HAZARD,HORN

ABS(BAT)

STARTER

Amps

25A 10A 10A 20A 10A 20A 10A 10A 10A 10A 20A 20A 20A 20A(Diesel) 10A(Gas) 10A 10A 20A 20A 10A 20A 20A(Diesel) 10A(Gas) 25A 10A

Heater

CircuitProtected

CompressorControls

ExhaustBrakeSystem(Diesel)

EngineControls(Gas) Headlights(Diesel) EngineControls(Gas) EngineControls(Diesel)

AutomaticTransmissionControls(Gas)

InteriorLights,ExteriorLights,SoundSystem(Gas), Speedometer(Gas)

DashLights,ExteriorLights BrakeLights

Headlights

WindshieldWiper/Washer ChargingSystem

TurnLights EngineControls

CigaretteLighter,EngineControls,SoundSystem

EngineControls EngineStopSystem(Diesel) EngineControls,Gauges(Gas) EngineControls,Gauges,Horn,HazardLights

ABS

StartingSystem

en di -n

FuseBox (b

6-1

This is the cut pages sample. Download all 260 page(s) at: ManualPlace.com