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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
60
40
80
110-1
12
12-3
10
10-4
130
33-1
21-2
.110-8
33
33-1
91
91
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.
2
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
WHT/GRN WHT/GRN | WHT/GRN | WHT/GRN | WHT/GRN | WHT/GRN ^JL- 25-Jl 21^6-10912J^ 13 | ElectronicBrakeControlModule(EBCM) Page44 | Page40 1 Module Page23-4 Page23-4 WHT/GRN HOTATALLTIMES -j HF-19 ) ABS(BAT J25A 1 1 Hazard Warning HOTINONANDSTART | n-|F-i3 ) ) TURN, LJSfLIGHT IDA 5 r" Switch Paael J^B-no [ 1 B-30 X ~1 1 10-7 GRN | 16j^B-79 DataLink Connector Pages23 and39 HOTATALLTIMES mF-i8 mF-i4 \ HAZARD \ ECU(IGN) L-IHORN LJlOA v^ GRN GRN | GRN r'JL'i i ri i i Horn | Engine ^iro 1 Relay Control Relay \ GRN | lJ^B-30 r i 1 l i -i Hazard Warning Switch Page110-7 -| -'Cab -A8"24 |Relay ~! 1Box 1 * | | J HOTINONANDSTART BLK/YEL BLK/YEL | BLK/Y 6^B-234 r i r i l l 1 i i- -i (FfMl Fuse Box 1 lJ^B-261 2-6
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
Headlights
WindshieldWiper/Washer ChargingSystem
TurnLights EngineControls
CigaretteLighter,EngineControls,SoundSystem
EngineControls EngineStopSystem(Diesel) EngineControls,Gauges(Gas) EngineControls,Gauges,Horn,HazardLights
ABS
StartingSystem
oo
en di -n
FuseBox (b
<h
6-1
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