1999 HONDA CIVIC ac line

(From page 11 148)(From page 11'148)
Roplac€ th€ Primary HOzS (Sen'
sor 11.ls there lessthan 2.8 V?
Substitute a known-good ECM
and recheck. lf symptom/indica'
tion goes awav, replace th€ odgi'
nalECM.
Check the ECM oulput voltage
(lP+ linel:Measure voltage between ECM
connector terminals C23 and D11
Substitute a known-good ECM
and recheck f symptom/indica-
tion goes awaY, replace the origi_
nal ECM.
ls there more than 0.4 V?
Check the ECM:1. Turn the ignition switch OFF.
2. Disconnect ECM connector C(31Plfrom the ECM.
3. Check for continuity between
body ground and ECM con-
nector terminal C23
Check fot an oPen in tha wire
llP+ linel:1. Turn the ignition switch OFF.
2. Disconnect the 8P connoctor
from the Primary HO2S (Sen-
sor'l).3. Check for continuity between
the PrimarY HO2S (Sensor 1)
8P connector terminal No. 7
and ECM connector termrnal
c23.
Repair open in the wire belween
ECM {C231 and Primary HO2S
{Sensor 11.
Substitute a known_good ECM
and r6check. lf symPlom/indica'
tion goos away, replace the odgi-
nalECM.
Check for a short in the wire llP+
line):1. Disconnect the 8P connector
from the Primary HO2S {Sen'
sor 1),2. Check for continuity between
body ground and ECM con-
nector terminal C23.
Repair short in lhe wire belween
the Primary HO2S (Sensor 'l) dnd
ECM {C23).
Replace the Primary HO2S (Sen'
sor 1).
sG2(GRN/BLKI
Wire side offemale termanals
PRIMARY HO2S(SENSOR 1l8PcoNNECTOR lC1a5l
lP+(BLK)
Wire side of
female termrnalsof femaleterminals
NO
(cont'd)
123a68910
111213141516171822
2125a30
I lP+
6) tBrK)
ECM CONNECTOR C {31P}
23a67II10
1112131l15161118,422
232a25A30
A lP+Ij/ IBLK)
11-149

t
The scan tool indicates Diagnostic Trouble Code (DTC) P1168; A low voltage problem in the Primary Heated
Oxygen Sensor (Primarv Ho2S) (Sensor 1) LABEL circuit'
- The MIL has b6€n reponed on'
- DTC P1168 is storcd
Problem vedfication:
1. Do the ECM Reset Procedure
2. Start the engine.
3. Wait at least two minutes
lntalmittent failure' aYstom b OK
at thi3 time. Chock lor Poor con-
nection3 or loo3o wiro3 at C145
(Primary HO2S, S.n.or 1l and
ECM.
ls DTC P1168 indicated?
Chock th. ECM:
1. Turn the ignition switch OFF.
2. Disconnect the ECM connec'
tor D 116P).3. Check for continuity between
ECM connector terminal D7
and body ground
Sub3titut. e known-good ECM
6nd r.chock. lf rymptom/indica-
tion gocr away, r.Placs the origi_
nal ECM.
Check for t shott in lhg wire3
ILABEL line):1. Disconnect the Primary HO2S
(Sensor 1) 8P connector'
2. Check for continuitv between
ECM connector terminal D7
and body ground
Reoair short in the wir63 botlvoon
lhe Primary HO2S {Sensor 1} end
ECM (O71.
ECM CONNECTOR D {16PI
LABEL {WHTI
wire side of female terminals
LABEL (WHTI
(cont'd)

PGM-FI System
IiT-"-w Heated 9{ygglSensor (primary HO2SI (Sensor 1)(Dl6Y5 engine with M/Tl lconr'd)
1T1163 Ih" scan tool indicates Diagnostic Trouble code (DTc) P1169: A high volrage probtem in the pnmary Heated- Uxygen Sensor {primary HO2S) (Sensor .l) LABEL circuit.
PSTMARY HO2S (SENSOR 1l8p CONNECTOR (145)
LABEL IWHTI
ECM CONNECTOR O {16P}
(GRN/BLK)
female
IGRN/BLKI
- The MIL hrs been reported on.- DTC Pl169 i3 stored.
Problem verification:L Do the ECM Reset Procedure.2. Start the engine.3. Wait at least two minutes.
Intormittent f.ilure, sv*em b OKat this time. Check for poor con-n.ctions or loose wires at C145(Prim.ry HO2S, Sensor 1l andECM.
ls DTC P1169 indicated?
Ch€ck Ior an op6n in th€ wire(LABEL line):1. Turn the ignition switch OFF.2. Disconnect the Primary HO2S(Sensor 1) 8P connector.3. Turn the ignition switch ON (ll).4. Measure voltage betweenPrimary HO2S lsensor 1) 8Pconnector No, 4 terminal andbody ground.
Check lor an open in the wire{SG2linel:1. Turn the ignition swilch OFF.2. Disconnect ECM connector D(16P)trom the ECM.3. Check for continuity betlveenECM connector terminal D1land Primary HO2S (Sensor 1)8P connector terminal No. 3.
ls there approx. 5 V?
Ropair opon in the wires betweonlhe P.imary HO2S {Sensor 't} andECM tD7l.
R€pair open in th6 wire betweenthe Primary HO2S lsensor 1) andECM (011).
ls there continuity?
Roplace the Primary HO2S (Sen-sor 1).
123a5
689101t12
t3141516sG2
side ofe terminalstll
II-- rl
;G2
I2
6
34
8
11-152

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
a
a
Heated Oxygen Sensor (HO2S) Heater
('96 - 98 Models,'99 - 00 D16Y5 engine with M/T) (cont'dl
PRIMARY HO2S {SENSOR 1I 4P CONNECTOR{c1231SECONDARY HO2S {SENSOR 2} 4PcoNNECTOR 1C125)r
r-l --'1
ll i2l
f;T;ttcl|BLK/ &)YELI Y
Wire side of fomale lerminals
SECONDARY HO2SISENSOR 2) 4P CONNECTOR{c78ilf
IBLK/WHT)
Wire side of lemale terminals
(From page 11-157)
Wire sid€ ot temale terminals
SO2HTC(BLK/WHTI* PO2SHTC{BLK/WHTI
*: P0141*+: Dl6Y8 engine
11-158
(From page 11-157)
Check tor an op6n or 3hoft in thewire {lGl lin6):Measure voltage between theHO2S 4P connector terminals No.3(D16Y8 engine: No. 4) and bodyground.- Repair open or shon in thewire between Primary HO2Slson.or 1), {No. 15 ALTERNA-TOR SP SENSORI (7.5 Al fuseand Secondary HO2S, Sonsol2t,.- Replace the No. 15 ALTERNA-TOR SP SENSOR 17.5 A) tuse.Check for an open in the wireIPO2SHTC, SO2SHTC' linel:1. Turn the ignition switch OFF.2. Reconnect the HO2S 4P con-nector.3. Disconnect the ECM/PCM con-nector A (32P).
4. Turn the ignition switch ON (ll).
5. Measure voltage between theECM,/PCM connector terminals46 and 410 {A5 and A10)*.
Ropail opan in the wire b€twoenECM/PCM lA6, A5l* and HO2S{Primary, Secondary+1.
ls there 0.1 V or less?
Substitute a known-good ECM/PCM and recheck. ll symptom/indication goes awry, repbcetho origin.l ECM/PCM.
ECM/PCM CONNECTOR A I32P)
so2sHrc ItBLK/WH0.J
pozsxtc E/
IBI-K/WHTI ^,-----{v}-|.=,|I
PG1IBLK}3u I JsTgT roll12r3t5t6Ittar920z2l 2321
25272A2i3o
Check tor a short in the wire{PO2SHTC. SO2SHTC* line):'1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector A (32P1.
3. Check for continuity betweenthe ECM/PCM connector termi-nal 46 (A5)* and body ground.
Repair short in thg wire betwe€nECM/PCM lA6, A5*l .nd HO2S(P.im.ry, Socondary*).
Substitute a known-good ECM/PCM and recheck. It symptom/indicetion goes away, rophcethe original ECM/PCM.

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}

PGM-FI System
Heated Oxygen Sensor (HO2S) Heater
('99 - 00 Models except D16Y5 engine with M/T)
(From page 11-159)
Substitute a known-good ECM/PCM and recheck. lf symptom/indication goes away, replacethe origin.l ECM/PCM.
(cont'dl
PRIMARY HO2S ISENSOR 1I 4P CONNECTOB{c123)SECONDANY HO2S ISENSOR 2} 4PcoNNECTOR (C125)*
-r--r ,
lr zl
-f-13 4llc'l L--r-J-r
relxr p1YELI Y
Wire side of temale terminals
SECONDARY HO2S(SENSOR 21 4P CONNECTOR{c782}rr
IG1 IBLK/WHT)
NO
Wire side of female telminals
ECM/PCM CONNECTORS
Wire side of female terminals
ECM/FCM CONNECTORS
*: P0141**: Dl6Y8 engine
1 1-1 60
Check for an open in the wires{lGl* line}iMeasure voltage between the primary HO2S 4P connector terminalNo. 3 (D16Y8 engine: No. 4) andbody ground.- Repeir open or shon in thewire between Primary HO2Slsensor 1), {No. 15 ALTERNA-TOR SP SENSOR) (7.5 A) fus€and Secondary HO2S, Sensor2t,.- ReDlace the No. 15 ALTERNA-TOR SP SENSOR {7.5 A tuse.
ls there battery voltage?
Check ,or an open in the wires(PO2SHTC, SO2SHTC' linel:1. Turn the ignition switch OFF.2. Reconnect the HO2S 4P con-nector,3. Disconnect the ECN4/PCM connector C (31Pi (ECM/PCM con-nector A (32P))i.
4. Turn the ignition switch ON (lli.
5. Measure voltage between theECM/PCM connector terminals82 and Cl 182 and AB)*.
Reprir open in the wirc betwo€nECM/PCM (Cl, A8i) and HO2S(Primary, Secondary+).
ls there 0.1 V or less?
(From page 11 l59i
Check tor a short in the wiresIPO2SHTC, SO2SHTC* linel:1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector C (31Pi (ECM/PCM connector A (32P)i*.
3. Check tor continuity betweenthe ECM/PCM connector terminal C1 {A8)* and body ground.
Repai. short in the wire b€tweenECM/PCM lcl, A8.l and HO2S(Pdmery, Secondary*1.
Substitute a known-good ECM/PCM end recheck. lf symptom/indication goes away, replacethe o.iginal ECM/PCM.
Wire side of female terminals