Page 212 of 1413
System Description
System Connectors IEngine Compartmentl
{818C1 onginol
ENGINEWIRE HARNESS
t3
c132
c131
UNDER,HOOOFUSE/RELAYaox
c102c222
ct 04c220
MAllrlWIREHARI{ESS
o
11-20
Page 216 of 1413
System Description
System Connectors [Dash and Floor]
PGM-FI MAINRELAY
C1I44 UNDEN-OASHFUSE/REALYBOX
ENGINECOMPARTMENTWIRE
DASHBOARO WIREHARNESS
MAINWIREHARI{ESS
REARWIREHARNESS
11-24
Page 218 of 1413
System Description
System Connectors [Dash and Floor] {cont'd}
UNDER-DASHFUSE/RELAYBOX
DASHBOARDHARNESS
MAINWIREHARNESS
11-26
Page 229 of 1413
It the inspection for a particular code requires the test harness. remove the right door sill molding and kick panel. Pull
the carpet back to expose the ECM, Unbott the ECM cover. Turn the ignition switch off and connect the test harness
Check the system according to the procedure described for the appropriate code(s) listed on the following pages.
KICKPANEL
TESTHARNESSOTLAJ _PT3OlOA
DIGITAL MULTIMETERCommarcially ovribbla orKS-AHM-32-OO3
NOT USED
TERMINAL LOCATIONS(cont'd)
o oooooooooooo
ooooooooooooo
oo o oo ooo
oooooooo
ooooooooooo
ooooooooooo
11-37
Page 231 of 1413

How to Read Flowcharts
A flowchrrt is dasigned to be us€d fiom start to final repair. lt's like a map showing you the shortest distanco. But be-
ware: if you go off tho "map" anywhere but a "stop" symbol, you can easily get lost
l6rffil Desclibas the conditions or situation to start a troubleshooting flowchart.(bold tyDo)
|TeTiONl Asks you to do something; pedorm a test, set up a condition etc'
<:6Eei6io-fr\> Asks you about the result of an action, then sends you in the appropriste troubleshooting direction.
I-SJTFI The snd of a series ot actions and decisions, describes I tinal repair action and aomotimea diracts
(bold typel you to 8n garlier part of the tlowchart to confirm your repair'
NOTE:
a Tha tarm ,,lntormittgnt Failure" is used in these chans. lt simply means a system may have had a failur6, but it chocks
out OK !t this time. lf th6 Msltunction Indicator Lamp (MlL) on ihe dash does not come on, check for poor connections
or loose wires at all connectors rolated to the cilcuit that you are troubleshooting (see illustration b6low).
a Most ot tho troublashooting flowchans have you reset the Engine Control Module (ECM) and try to duplicate the Disg-
nostic Troubls Cod6 (DTC). lf the problem is intermittent and you c8n't duplicat€ the cod6, do not continus through
the flowchart, To do so will only rosult in confusion and, possibly, a ne€dlessly replaced ECM
a ,,opon,'and ,,short,, are common electrical terms. An open is a break in a wir6 or at a conn€ction. A short is an
accidontal connaction ot a wir€ to ground or to another wire. In simple electronics, this usually means som€thing won't
work at all. In complex electronics (like ECM's), this can sometimes mean something wolks, but not the way it's sup-
poSad to,
a il th6 olectricsl readings are not as specified when using the test harness, check the test harness connoctions bsfore
procooding.
LOOSE
11-39
Page 234 of 1413

PGM-FI System
Engine Control Module (ECM)
lB18B1 ongino onlyl
The Malfunction Indicator Lamp(MlL) n6v6. com6s on lovon follwo socondal aftor ignition istumed on.
lurn the ignition switch ON.
Inspect No. 15 {BACK-UP LIGHT}l1O A) luse in the underdashtuse/relay box.ls the low oil pressure light on?
- R€placo No. 'l5
IBACK-UP LIGHT)llo Al fuso.- Ropair short inYEL wiro botwoonNo. 15 (BACK-UP
LIGHT) {10 A) fusoano gauge 6$om-blv.
Turn lhe ignition switch OFF.
ls the fuse OK?
Connecl the test harness betweenthe ECM and connectors (seepag€ 11-37).Repair opon in YEL wiio botw6onNo.'15 IBACK-UP LIGHTI 110 A)luso and gaug6 assombly.
Turn the ignition switch ON.
- RsDlaco tho MIL bulb.- Ropair opon in GRN/ORN wi.ebetwoen ECM {A13} andgaug€ a$6mbly.
ls the MIL on?
Measure voltage between body
Oround and the tollowing termi-nafs individuallv: 423, 424.
Ropah op6n in BLK wirolsl bo-tw6en ECM and GlOl llocatod atthormostat housing) that hadmoro than 1.0 V.
ls there less than 1.O V?
Substituto a known-good ECMand rochgck, lf symptom/indica-tion go€s away, roplaco tho origi-nal ECM.
NOTE: lf this svmptom is intermittent. check for a loose fuse No. 15 (BACK
UP LIGHT, 1OA) in the under-dash Juse/relay box, a poor connection at ECM
terminal A13, or an intermittent open in the GRN/ORN wire between the ECM(A13) and the gauge assembly.
I A13
I| | o oooo oooooooo I oooo oooo I ooooool ooooooooooo I
G 10' l
11-42
Page 235 of 1413

Th. ll.lfunction Indicltor Lamp
lMlll at!y3 on o. cornaa on alt6ltwo aacond!.
Connect the SCS short connectorto th6 sorvice check connector(see page 11-34).
Turn the ignition switch ON.
Go to iolfdiagnostic Proceduros(se€ pago 11-34).Does the MIL indicate anv Oi-agnostic Trouble Code (DTC)?
Romove th€ SCS shon connectorlrom the service ch€ck connector.
Turn the ignition switch OFF.
Try to start the engine.
Connect the test harness betweenthe ECM and connectors (see
page 11-37).
Turn the ignition switch ON.
Measure voltage botween D4 (+ )terminal and D22 { - ) terminal.
connect the SCS shonconnector to servlcecheck connector.ls there approx. 5 V?
Ropair shon to body g.ound inBRN/WHT wire betwoon th6 ECMlD4) end sorvlco chock connocto?.Measure voltage be_tween D4 {+} terminaland body ground.
- R6pair open in BRN/WHT witobotwoon EcM lD4) and s6rv-ice chock connactor.- Repoir opon in BLK wiro bo-twoon 36rvi@ chock connectoaand G4Ol.
ls there approx. 5 V?
InsDoct ECU {ECM) 115 A) tuse inth6 undeFhood luse/relav box.
- Rsolaco ECU {ECM} (15 Allus€.- R6pair shon in YEL/WHT wilobotw6on ECU lEcMl 115 A)fuso and PGM-FI main rolay.
Remove the scs shortConnector from theservice check con-nector.
ls the luss OK?
NOTE:
a When there is no code stored, the MIL willstay on if the service check con-
nector is shorted.
a tf this svmotom is intermittent, check for:
- A loose ECM fuse (15A) in the under-hood tuse/relay box
- A loose No. 24 fuse (ACG) (ALT) ( 1 5A: B1 8B 1 engine, 2OA: B18C 1 en-
gine) in the under-dash fuse/relay box- An intermittent short in the BRN/WHT wire between the ECM (D4) and
the service check connector- An intermittent oDen in the BLK wire between the service check con-
nector and G4O1- An intermittent shon in the GRN/ORN wire between the ECM (A 13) and
the gauge assembly.- An intermittent short in the YELMHT wire between the ECM (D19) and
the MAP sensor- An intermittent short in the YEL/BLU wire between the ECM (D20) and
the TP sensor
o ooooo ooo ooo o loooooooo liii:$A$.Ps,l o oo ooo ooooo
o oooo ooo o o ooo I oooooooooooooooooo
D4 (+)
l"oo,o'.
D22 t-l
uu,l
'NOTE: After repair, disconnect the SCS ShortConnsctor, test drive the car, and recheckthe MIL
lor a code.
(cont'd)
(To page 1 'l -44)lTo page 1 1-44)
11-43
Page 236 of 1413

(From page 1 1-43)
Inspect the No. 24ACG {ALT) (lG)(15 A: 81881 engine, 2OA:818C1 enginel fuse in the under-dash fuse/relav box.
- R.pllr .hon in BLK|rEL wlr6batr.v€qr undariair luro/Fbybox lnd FGM-FI m.in .obv.- noebco lto. 24 ACG {lG) nLT)(15 A: 81881 ongin., 2OA:Bl8Cl onein.l tu!6.
ls the fuse OK?
Turn the ignition switch ON.
Disconnect the 3P connector oteach sensor one al a time:. MAP sensor. TP sensor
Rcplaoo thg lgnlor that caur6dth. llght to Oo out.Does the MIL remain ON?
Turn the ignition switch OFF.
connect the test harness.Disconnect the "D" connectorfrom th€ ECM only, not the mainwire harness (see page 11-37).
Check tor continuity betweenbody ground and D19, O2O ter-minals,
- Bapai? rhod ro body g.ound inYEL/WHT wi.e boiwoon ECM(Dl9) .nd MAP ..n3or.- R.p!k shon to body ground inYEL/BLU wire b.lwo6n ECM(O2Ol .nd TP 3on!or.
Reconnect all tho sensor con-necrors,Reconnect the "D" connector torhe ECM.
Turn the ignition switch ON.
{To page 11-45}
System
Control Module (ECMI (cont'dl
PGM-FI
Engine
Dt9I
I oooooooooo ooo I oooooooo I omoool o oooooooooo | |I ooooooooooooo I oooooooo 1o('oe(lo I ooooooooooo | |-lD2O I
\-.J
Continuity?
(From page 11-43)
Disconnect "A" con-nector from the ECM.
Subrtltute r knowngood ECM.nd rochock. ll lymptom/indics-tlon g@a rw!y, rephco tho origi-n.l ECM.
ls the MIL ON?
Ropair short to bodygiound in GRN/ORNwir6 botwoon tho ECMlA131 6nd MlL.
11-44