How to Read Flowcharts
A flowchart is designed to be used from start to final repair. lt's like a map showing you the shortest distance. But beware:
lf you go off the "map" anywhere but a "stop" symbol, you can easily get lost.
tSrARTl(bold type)
FanoNl
@
tsroP I
{bold type)
Describes the conditions or situation to start a troubleshooting flowchart.
Asks you to do something; perform a test, set up a condition etc.
Asks you about the result of an action, then sends you in the appropriate troubleshooting direction.
The end of a series of actions and decisions. describes a final repair action and sometimes directs you to
an earlier part of the flowchart to confirm your repair,
NOTE:
. The term "lntermittent Failure" is used in these charts, lt simply means a system may have had a failure. but it checks
out OK at this time. lf the Malfunction Indicator Lamp (MlL) on the dash does not come on, check for poor connections
or loose wires at all connectors related to the circuit that you are troubleshooting (see illustration below)'
. Most of the troubleshooting flowcharts have you reset the Engine Control Moduls (ECM)/Powertrain Control Module
(pCM) and try to duplicate the Diagnostic Trouble Code (DTC). lf the problem is intermittent and you can't duplicate the
code, do not continue though the flowchart. To do so will only result in confusion and, possibly, a needlessly replaced
ECM/PCM.
. ,,Open" and "Short" are common electrical terms. An open is a break in a wire or at a connection. A short is an acci-
dental connection of a wire to ground or to another wire. In simple electronics, this usually means something won't
work at all. In complex electronics (like ECM's/PCM'sl. this can sometim€s mean something works, but not the way it's
suDDosed to.
toosE
1 1-103
I
Engine Control Module/Powertrain Control Module (ECM/PCM)
t'96 - 98 Models,'99 - 00 Dl6Y5 engine with M/Tl
L
NOTE: lf th is svmptom is intermittent, check for a loose fuse No. 25 {METER 7.5 A) in the
underdash {use/relay box, a poor connection at ECM/PCM terminal A18, or an intermit
tent ooen in the GRN/ORN wire between the ECM/PCM (A18) and the gauge assemblv.
ECM/PCM CONNECTOR A I32PIPGl {BLKI
Wire side ot female terminals
ECM/PCM CONNECTOR A (32P}
Wire side of female terminals
(cont'd)
11-107
The Malfunc{ion Indicator Lamp
{MlLl never comes on (even lor
two secondsl atter ignition is
turned on.
Turn the ignition switch ON (ll).
- Repair short or open in thewile botwoen No. 25 {M€TERI
17,5 Altus€ and gau99 assem'
bty.- Replaco No.25 IMETERI (7,5
A)tuse.
ls the low oil pressure light on?
Try to start the engine.
Does the engine stan?
Check lor an open in the wiles
{PG linosl:1. Turn the ignition switch ON (ll).
2. ldeasure vo ltage betweenbody ground and ECM/PCMconnector terminals A10 andA23 individually.
Check tor an open in the wire ot
bulb (MlL line):1. Turn the ignition switch OFF.
2. Connect the ECM/PCM con-nector terminal A'18 to bodyground with a jumper wire.3. Turn the ignition switch ON (ll).
Repair open in the wire(s)
between ECM/PCM and G101(localod at the thetmostat hous_ingl that had more than 1.0 V.
ls thore less than 1.0 V?
Substituto . known-good ECM/PCM and recheck. It symptom/indication go6s away, roPlace
the origin.l ECM/PCM.
- Repair open in th€ wiresbetwoen ECM/PCM lAl8l andgaug6 a$embly.- Replace the MIL bulb,
ls the MIL on?
Substitute a known-good ECM/
PCM and .echeck. lf symptom/indication goes away, replacothe origin.l ECM/PCM.
268l011
12l3t5t61tIt192022232a
2527xt30
MrL I luanpen wrnrIGRN/ORN) I
!1,
PGM-FI System
Engine Control Module/Powertrain Control Module (ECM/PCMI
('96 - 98 Models,'99 - 00 Dl6Y5 engine with M/Tl (cont'd)
NOTE:. When there is oo Diagnostic Trouble Code (DTC) stored, the MtL wi
stay on if the SCSservace connector is connected and the ignition switch is on,. lf this symptom is intermittent, checklor:- A loose Fl E/M 115 A) fuse in the under hood luse/relay box- A loose No. 13 FUEL PUMP fuse (15 A) in the underdash fuse/relay box- An intermittent shon in the wire between the ECM/PCM (C7) and the service cnecKconnector- An intermittent short in the wire between the ECM/PCM (A18) and the gaugeassembly- An intermittent shon in the wire between the ECM/PCM {D4) and the MAp sensorAn intermittent short in the wire between the ECM/PCM (D10), the Tp sensor, theEGR valve l:ft sensor (D16Y5 engine) and/or the Fuel tank pressure sensor (,96Dl6Y8 engine (coupe), '97 016Y7 engine (coupe: KL model, sedan: KL (LX) modeli,'97 016Y8 engine {coupe: all models, sedan: KL modeti,'98,all models}- PGM-FImain relay. See the OBD ll scan tool or Honda PGM Tester user's manuals lor specitic operatinginstructions.
ECM/PCM CONNECTOR C 13lPI
Wire side of female terminals
(To page 11 109)
(To page 11,109)
11-108
The Maltunction Indicator Lamp(MlLl stays on o. comes on eftartwo s€conds,
Check the Oiagnoslic TroubleCode {DTC}I1. Connect a scan tool or HondaPGM Tester.2. Turn the ignition switch ON (ll).
3. Read the DTC with the scantool or Honda PGM Tester.
Go to troubleshooting p.oc€dur€s(se€ pago 11{11.Are any DTC{s) indicated?
Check the DTC by MIL indication:1. Turn the ignition switch OFF.2. Connect the SCS service con,nector to the service checkconnector.3. Turn the ignition switch ON (lli.
Repair opon ol short in wirebotwoen the ECM/PCM (C8)
and Data Link Connector.Go to troublelhooting proce-dure ls6e page 11-811.
Does the MIL indicate any DTC?
Try to start the engine.
Does the engine start?
Check for a short in the wire(SCS lin€l:1. Disconnect the SCS serviceconnector.2. Stop the engine and turn theignition switch ON {lli.3. Measure voltage between theECM/PCM connector terminalC7 and body ground.
Ropair short to body Iround inthe wire betweon ECM/PCM lCTland sorvice check connector.
ls there approx. 5 V?
scs tBRNI
lFrom page 11 108)
Check for a short in the wire {MlLlinell1. Turn the ignition switch OFF.
2. Disconnect the Eclvl/PCM con-nector A (32P).
3. Turn the ignition switch ON {ll).
Ropair short to body gtound in
the wir. between the ECM/PCM
lA18) and MlL.ls the MIL ON?
Substitute a known-good ECM/
PCM and recheck. lt 3ymptom/indicaiion goes away, rePlace
ihe original ECM/PCM.
(From page 11 108)
Inspect Fl E/M (10 A) fuse in theundeFhood Iuse/relay box.
- Repair short in the wirg
b€tweon Fl E/M (15 A) luse
and PGM-FI main rolay.- Replace Fl E/M (15 Alfuse.
Inspect No. 13 FUEL PUMP (15 A)
fuse in the under-dash fuse/relaY
- Repait lhort in the wire
botween No. 13 FUEL PUMP
115 Al fuse and PGM-FI main
reray.- Roplace No. 13 FUEL PUMP115 Al tu3o.
Check for a short in a 3€nsor:1. Turn the ignition switch ON (lli.
2. Disconnecl the 3P connectorfrom each sensor one at time:
. TP sensor. EGR valve lift sensor (D16Y5
engrne). Fuel tank pressure sensor('96 D16Y8 engine (coupe),'97 D16Y7 engine (couPe:
KL model, sedan: KL (LX)
model),'97 D16Y8 engine
lcoupe: all models, sedan:KL model,'98-all models)
{To page 11 110)(cont'd)
1 1-109
!
Engine Control Module/Powertrain Control Module (ECM/PCM)
('95 - 00 Models except Dl6Y5 engine with M/T)
NOTE:. When there is no Diagnostic Trouble Code lDTC) stored, the MIL will staY on if the SCS
seruice connector is connected and the ignition switch is on.. lf this symptom is intermittent, check for:- A loose No. 25 (METER) {7.5 A) fuse in the underdash fuse/relay box- A loose Fl E/M (15 Alluse in the undeFhood fuse/relay box- A loose No. 13 FUEL PUMPfuse (15 A) in the under-dash fuse/relay box- An intermittent shon in the wire between the ECM/PCM (A18) and the gauge assem'
- an intermittent short in the wire between the ECM/PCM (C19) and the MAP sensor- An intermittent short in the wire between the ECM/PCM {C28), the TP sensor, the
EGR valve lift sensor (D16Y5 engine) and/or the Fuel tank pressure sensor ('96 D16Y8
engine (coupe),'97 D16Y7 engine lcoupe: KL model, sodan: KL (LX) model)"g7
Dt6Y8 engine (coupe: all mod;ls, sedanl KL model),'98-all models,'99-al' models''00-all models.- PGM'FI main relay. See the oBD ll scan tool or Honda PGM Tester user's manuals for specific operating
instructrons,
ECM,/PCM CONNECTOR A I32PI
Wire side of {emale terminals
The Mrlfunction Indicator LamP{MlL) never comes on {even tor
two seconds) after ignition is
turned ON lll).
Turn the ignition switch ON lll).
- Repair shott or open in thowire bstwoon No. 25 IMETER)l?.5 A)tuse and gauga tsom_blv.- Reolace No. 25 (METERI (7.5
Alluse.
ls the low oil pressure light on?
Try to start the engine.
Check for an opon in the wire orbulb (MlL line):1. Turn the ignition switch OFF.2. Connect the ECM/PCM con'
nector terminal A18 to bodyground with a iumper wire.
3. Turn the ignition switch ON (ll)
Does the engine start?
- Repair open in tho wire3
betwoon ECM/PCM (A18) andgaugo .*tembly.- Rool.ce the MIL bulb.
Substitute a known-good ECM/
PCM and rochoc&. lf sYmptom/indication goes sw6y, repl.ce
tho original ECM/PCM.Turn the ignition switch OFF.Inspect Fl E/M (15 A)fuse in theunderhood Iuse/relay box.
Rop.ir short in the wirc
betwo€n Fl E/M (15 A) luso
and PGM-Fl mrin rGl.y.Reol.ce Fl E/M (15 A)tusa.
lnspect No. 13 FUEL PUMP {15 A}
luse in the under-dash fuse/relay
- Reoair short in the wiro
between No. 13 FUEL PUMP
115 Al luse sod PGM-FI mainrelay.- Reolace No. 13 FUEL PUMP115 A) tuse.
(To page 11 112)
(cont'd)
11-111
.f,
Secondary Heated Oxygen Sensor {secondary HO2S) (Sensor 2l
*'t : D16Y8 engine*2:'99 - O0 m;dels except D16Y5 engine with M//T
The scan tool indicates Diagnostic Trouble Code (DTC) P0137: A low voltage problem in the Secondary Heated
Oxygen Sensor (Secondary HO2S) (Sensor 2) circuit'
SECONDARY HO2S ls.n.ot 2),rP CONNECTOR (C125, C782')
Wire side oI temale terminals
(cont'd)
1 1-153
- Tho MIL has been reported on- DTC P0137 is stored.
Problem verification:1. Do the ECM/PCM Reset Pro
cedure.2. Start the engine. Hold the
engine at 3,000 rpm wlth no
load (in Park or neutral) until
the radiator fan comes on
3. With the scan tool, check the
Secondary HO2S (Sensor 2)
output voltage at 3,000 rPm
lntermittent frilure, sYdem is OK
at this tim6. Check for Poor con'
nections or loolo wir.3 at C131t(locatod undor right.ido of desh)'
C432. {located under middle of
dashl, cl25 lc782lr {SecondaryHO2S) tsensor 2l .nd ECM/PCM.
Does the voltage staY at 0.3 V
or less?
Ch6ck tot a sho.t in the S€condery
HO23:'1. Turn the ignition switch OFF.
2, Disconnect the SecondarY
HO2S lSensor 2)4P connector.
3. Start the engine.
4. Check the SecondarY HO2S
lsensor 2) output with the scan
tool,
Check tor a short in the wire
{SHO2S linel:1. Turn the ignition switch OFF.
2. Discon n ect tho EcM/PCM
connector D {16P) {A (32P))*'
3. Check for continuity between
the SecondarY H02S (Sensor
2) 4P connector terminal No 1
and body ground.
R€pair short in tho wire bstwoen
ECM/PCM lD14 (A231*' | and
Secondarv HOzS (Sensor 2).
Substitute a known-good ECM/
PCM and recheck lf 3ymptom/
indicalion go€s awaY, tePltco
the oiigin.l ECM/PCM.
Secondary Heated Oxygen Sensor (SecondarytlO2S) (Sensor 2l
('99 - 00 lilodels except DtGYS engine with M/T)
The scan tool indicates Diagnostic Trouble code (DTC) P0138: A high voltage problem in the secondary Heated
Oxygen Sensor (Secondary H02S) (Sensor 2) circuit.
SECONDARY HO2S {S€nsot 2}
4P CONNECTOR Cl25 lc782l'
JUMPER WIRE
Ir
sH02s(WHT/RED)sG2{GRN/BLKI
Wire side of female termanals
ECM/PCM CONNECTORS
A (32P1
Wire side ot female termlnals
gs92g 111yp17p5py | .lutuPea wtne
- The MIL has beon reportod on.- DTC m138 is.tored.
Ploblem vorification:1. Do the ECM/PCN4 Reset Pro-
cedure.2. Start the engine Hold the
engine at 3,000 rpm with no
load (in Park or neutral) until
the radiator{an comes on
3. Check the SecondarY H02S(Sensor 2) output voltage at
3,000 rpm with the scan tool
lntormittont failuio, sYstom b OK
st thir timo. Check for Poor con_
nections ot loo39 wiJo3 af Cl3lr(located under right ride ot desh),
C432' (locatod undot middle of
dashl, Cl25 {C782lr (Secondaiy
HO2S Son3or 2l and ECM/PCM.
Does the voltage stay at 0 6 V
or more?
Ct€d( tor an opan in the Secondary
l|o2s:1. Turn the ignition switch OFF
2. Disconnect the SecondarY
HO2S (Sensor 2) 4P connector.
3. Connect the Secondary HO2S(Sensor 2) 4P conneclor ter_
minals No. 1 and No.2 with a
iumper wire.4. Turn the ignition switch ON (ll)
5. Check the SecondarY HO2S
lSensor 2) outptlt voltage with
the scan tool,
lsthere 0.6 V or more?
Check lor an open in the wiro(SHO2S line):1. Turn the ignition switch OFF.
2. Connect ECM/PCM connector
terminals A23 and C18 with ajumper wrre,
3. Turn the ignition switch ON (ll).
4. Check the SecondarY HO2S
{Sensor 2) outPut vo ltage
with the scan tool.
Repair opon in tho wire betwecn
ECM/PCM (A23) and SocondarY
HO2S {Sansor 2).ls there 0.6 V or more?
Substitut€ a known'good ECM/
PCM and recheck. It symptom/indication goes awey, JePlaco
the otiginel ECM/PCM
*i 016Y8 engine1 1-155
PGM-FI System
Secondary Heated Oxygen Sensor (Secondary HO2S) {sensor 2l
[FO13a]l The scan tool indic€tes Diagnostic Trouble Code {DTC) P0139: A slow response probtem in the Secondary Heated- Uxygen Sensor (HOzS) (Sensor 2) circuit.
1 1-156
- The MIL has been reported on.- DTC P0139 is stored.
Problem verification:1. Do the ECM/PCM Reset Pro-
2. Start the engine. Hold theengine at 3,000 rpm with noload {in Park or neutral) untilthe radiator fan comes on.3. With the scan tool, check theSecondary HO2S (Sensor 2)output at 3,000 rpm.
Intermiftent failure, system i! OKat this tims. Check for pool con-nections or loos6 wiles at C131.{located undor ght lide of dash),C432' (locrted under middle otd.shl Cl25 (C782lr (SocondaryHO2S) (Sonsor 2) and ECM/FCM.
Does the voltage stay within0.3 - 0.6 V for two minutes?
*: D16Y8 engine