1999 HONDA CIVIC C131

System Description
Electrical Connections ('99 - 00 Models except Dl6Y5 engine with M/Tl
(cont'dl
DRIVE PULIEY SPEEO SENSOF
SECONDAFY GEAFSHAFT SPEEO SENSOR
SCLSM
INHSOL
PNK/BLK
YE!'
PNK/BIU
cnvauC
c131 CrKa
GFN/Brf I f cnvsuCL_
,T GEAF POSII|ON SWITCH
11-48

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.

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

tFo135l
iPol4tl
Heated Oxygen Sensor (HO2SI Heater
('96 - 98 Mbdels,'99 - 00 Dl6Y5 engine with M/Tl
*: p0141 (To page 11-158)**: D'16Y8 engane
The scan tool indicates Diagnostrc Trouble code (DTC) P0135: An electrical probl€m in the Primary Heated
Oxygen Sensor (Primary HOiS) (Sensor 1) Heater system (Except D16Y5 engine with M/T)'
The;can tool indicates Diagnostic Trouble code (DTC) P0141: A problem in the secondary Heated oxygen sensor
(secondarv HO2S) (Sensor 2) Heater circuit.
PRIMARY HO2S (Son.or 1l aP CONNECTOR
SECoNDARY HO2S tsensor 2l ilP CONNECTORT
Terminal side of male terminals
PRIMARY HOzS (SENSOR 1) 4P CONNECTOR ICl23I
SECONDARY HO2S ISENSOR 2) 4P CONNECTOR {C125I*
PO2SHIC, SO2SHTCIBLK/WHT)
Wire side of female terminals
SECONDARY HO2S ISENSOR 2),tP CONNECTOR 1C782)'*
so2sHTC{BLK/WHT)
Wire side oI female terminals
I(cont'd)
11-157
- The MIL h.s boen Jeponed on.- DTC P0135, and/or Polal .re
stoled.
Problem verificationl
1. Do the ECM/PCM Reset Pro-
ceduae,2. Start the enginelniermittent tailura, sYttam i! OK
at thi3 time, Chsck for Poor con'
neciion3 or loose wilG3 at
C131** (locat.d undo. right sido
ot dashl, C{32** (loc.ted under
middle ol dashl, C123 (PrimarY
HO2S. Sansor 1) C125 lc782l*r
{Socondery H02S, Sonsor 2l'
and EcM/PcM.Check for an open or 3hort in tho
HO25:1. Turn the ignition switch OFF.
2. Disconnect the HO2S (Primary
or Secondary*) (Sensor 1 or
Sensor 2) 4P connector'3. At the Ho2s side, measure
resistance between the HO2S
4P connector terminals No. 3
and No.4.
ls there 10 - 40 0?
Check for continuity between
body ground and the HO2S 4P
connector terminals No. 3 and
No.4 individually
Chock for an oPen ot short in tho
wire |PO2SHTC, SO2SHTC* linol:
1. Turn the ignition switch ON (ll).
2. Measure voltage between the
HO2S 4P connector terminalsNo.3 and No.4.
(To page 11'158)

IHeated Oxygen Sensor (HO2S) Heater
i'ss - oo Mb-dels except D16Y5 engine with M/Tl
The scan toot indicates Diagnostic Trouble Code (DTC) P0135: An electrical problem in the Primary Heated
Oxygen Sensor (Primary ttOiS) (Sensor 1) Heater system {Except D15Y5 engine with M/T)'
The
-scan tool indicates Diagnostic Trouble Code (DTC) P0141; A problem in the Secondary Heated Oigen Sensor
(Secondarv HO2S) {Sensor 2) Heater circuit
Fo13sl
Fol11l
lntermiftent failuro, sYstom b OK
at thit limo. Ch6ck lor Poor oon'
nectiont or looso wita! at
C131'* {loc.tod und.t right ido
ol drshl, C432'* (located undel
middlo of dashl, C123 (PrimarY
HOzS, Sensor 1) C125 (Ct82lr'
(socondary HO2S, Sensor 2)t
.nd ECM/PCM.
PRIMAFY HO2S ls.n.or ll rrP CONNECTOR
SECOITIDARY HO2S (Srn.ol21 4P CONNECTOR'
Terminal side of male terminals
PRIMARY HO2S {SENSOR 1} ilP @NI{ECTOR lc123l
sEcoNDARY HO2S ISENSOR 2) aP @NNECTOR (C125)'
3l-, l-tl-t Fo2sHrc. so2sHrc
ver.t l ^-1 .'l {BLK/wHrl
11 '!'l-l
| --=- Iu----{v)'---..-'
Wire side of {emale terminals
SECO'TIDARY Ho2S (SENSOR 2,
4P CONNESTOR {C7&llt'
so2sHTc(BLKnflHTlIBLK/WHT)
(cont'd)
1 1-159
Wire side oI female terminals
r: p0141 {To page 11-160}**: D16Yg engine
- The MIL has been reponed on.- DTC P0135. and/or P0141 are
storod.
Problem vorification:1. Do the ECM/PCM Reset Pro-
cedute.2. Stan the englne.
Chock foi an open or short in the
HO25:1. Turn the ignition switch OFF
2. Disconnect the HO2S (Primary
or Secondary*) lSensor 1 or
Sensor 2) 4P connector'
3. At the H02S side, measure
resistance between the HO2S
4P connector terminals No. 3
and No.4.
ls there 10 - 40 n?
Check for continuity between
body ground and the HO2S 4P
connector terminals No. 3 and
No.4 individuallY.
Check for an opon or short in lho
wire (PO2SHTC, SO2SHTC+ line):'1. Turn the ignition switch ON (ll).
2. Measure voltage between the
H02S 4P connector termlnalsNo.3 and No.4.
{To page 11-160}

Electrical Load Detector (ELDI {'96 - 98 Models,'tn - 00 D16Y5 engine with M/T}
The scan tool indicates Diagnostic Trouble code (DTC) P1297: A low voltage problem in the Electrical Load
Detector (ELD) circuit.
ELD 3P CONNECTOR (c35'rl
l-- ,ll l2l3l--f ..
ao (GRN/REDI
Y
ECM/PCM CONNECTOR O I16PI
Wire side of female terminals
Problem verification:'!. Do the ECM/PCM Reset Pro-
cedure.2. Sta rt the engine
3. Turn on headlightslntermittent tailure, sYstem is OK
at this time. Check for Poor con-
nection3 or loose wires at C131
tlocated under righl side of da3h).
C354 (ELDIand ECM/PCM.
ls DTC P1297 indicated?
Ch.ck lor short in the ELD:
Measure voltage between body
ground and the ELD 3P connector
terminal No.3.
ls there approx.4 5 V?
Check for a short in tho wile (EL
linel:1. Turn the ignition switch OFF'
2. Disconnect the ECM/PCM con
nector D (16P)
3. Check for continuity between
body ground and ECM/PCM
connector terminal D16
R6pair short in the wire between
ECM/PCM (D161and ELD.
Substitute a known-good ECM/
PCM and recheck lf symplom/
indication goes awaY, rePlace
the original ECM/PCM
ra
11-179

PGM-Fl System
Elestrical Load Detector |ELD) t'glf - 00 Models except D16y5 engine with M/Tl
The scan tool indicates Diagnostic Trouble Code (DTC) P'1297; A low voltage probtem in the Electrical LoadDetector (ELD) circuit.
ELD 3P CONNECTOR tC354)
EL{GRN/REOI
ECM/PCM CONNECTOB A I32PI
Wire side of lemale terminals
Problem verilication:1. Do the ECM/PCM Reset Pro-cedure.2. Sta rt the engine.3. Turn on headlights.
Inlermittont failur6. systom i3 OKat this time, Chock tor ooor con-nestions or loose wires at C131(locrted undor ight side ot d.shl,C354 (ELDI and ECM/PCM.
Check for short in th6 ELD:Measure voltage between bodyground and the ELD 3P connectorterminal No.3.
ls there approx. 4.5 V?
Check to. a short in the wne (ELlinel:'L Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector A (32P).
3. Check tor continuity betlveenbody ground and ECM/PCMconnector terminal A30.
Repair short in the wile betweenECM/PCM lA30) and ELD.ls there continuity?
Sub3titute a known-good ECM/PCM and rech€ck. It symptom/indication goes away. replacethe o.iginal ECM/PCM.
1 1-180

Elestrical Load Detector (ELD) f96 - 98 Models''99 - 00 D16Y5 engine with M/T)
ThescantoolindicatesDiagnosticTroubleCode(DTC)P1298:AhighvoltageproblemintheElectricalLoad
Detector (ELD) circuit
ELD 3P CONNECTOR {G's'I
Wire side ol female terminals
EL IGFN/REDI
Problom vcrificttion:
1. Do the EcM/PClVl Reset Pro-
cedure,2. Start the engine.
3. Turn on headlights.lntarmitt..rt l.ilur., ryttcm b OK
.t thia tim. Ch.ck lor Poo' con-
nections or looaa wir.3 at C131
lbcd.d und.r right ide ol dalhl'
Gl5a {EU)} .nd ECM/PCIYI
ls DTC P1298 indicated)
Ch.ck lor tn oPan in tho wir'
(lGl linol:1. Turn the ignition and head'
liohts OFF2. D]""onn""t the ELD 3P con_
nector-3. Turn the ignition switch ON {ll)'
4. Measure voltage between body
ground and the ELD 3P connec
tor terminal No. '1.
R.oair ogan in tha wira Mw"n
ru". rs ltTEnrlton SP SelSOn
t?.5 A, fu!. in th. undcr-dr3h
tu3e/r.l!Y box .nd ELD.
Chcck lor tn oP.h in thc wire
{GND lincl:1. Turn the ignition switch and
headlights OFF.
2. Disconnect the ELD 3P con_
nector'3. Check for continuity between
body ground and the ELD 3P
connecto. terminal No 2
Raprir opcn in the wira bstwt€n
ELD conncctor lnd G/O2.
Ch.ck lor !n oplo in tha wirc IEL
lin.l:Check for continuity between the
ELD 3P connector terminal No 3
and ECM/PCM connector termi
nal D'16.
Rapaii opcn in the wira b€tw"n
ECM/FCM (I)161 .nd th. ELD'
Ch.d( fo. r m.llunction in thc ELD:
1. Reconnect the ELD 3P con'
2. Start th€ engine and allow it
to idle.3. Wh ile measuring voltage
beNveen ECM/PCM connector
terminals D16 and A9, turn
the headlights on {low).
Does the voltage droP?
Sub3titut. . known_good ECM/
PCM .nd rcch.ct. lt sYmptom/
indication goas away/ iapllc'
thc origin.l ECM/PCM
wire side of lemale termrnals
Wire side of Iemale terminals
t'a
)
1 1-181