1996 HONDA CIVIC engine wire

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

Heated Oxygen Sensor (HO2SI Heater (Dl6Y5 engine with M/Tl
The scan tool indicates Diagnostic Trouble Code (DTC) P1166: An electrical problem in the Primary Heated
Oxygen Sensor (Primary H02S) Heater system.
PRIMABY HO2S ISENSOR 1I 8P CONNECTOR
Terminal side ofmale terminals
I(cont'd)
11-161
- The MIL has been lePorted
- DTC Pl166 b stored.
Problem verilication:1. Do the ECM Reset Procedure.
2. Start the engine.
Intermitlent failura, sYstem b OK
at this time (te3t drive maY be
ngcessary). Check for poor con-
nections or loose wires between
C145 (Primary HO2S, Sen3or 1l
end ECM.
ls DTC P'l166 indicated?
Check the Primary HO2S (Sensot
1l resistence:1. Turn the ignition switch OFF
2. Disconnect the Primary HO2S(Sensor 1) 8P connector.
3. At the Primary HO2S (Sen
sor 1), measure resistance
between No. 1 and No. 2 ter_
Replace lhe Primery HO2S (Sen-
sor 11.ls there 2 13 O?
Check for a shorted PrimarY
HO2S lsensor 1):Check for continuity between
body ground and each terminal.
Check for a shorted PrimarY
HO2S {S€nsor 1l:
Check for continuity between ter'
minal No. 1 and terminals No.3,
4, 6, 7 and 8 individually.
ls there conlrnuily?
(To page 11'162)

PGM-FI System
I
a
a
Ch6ck the PO2SHTC circuit:1. Start engine and keep enginerpm at idle.2. At the engine wire harness,measure voltage betweenPrimary HO2S (Sensor 1) 8Pconnector terminal No. 1 terminal and body ground.
Check for an open in the wire(PG linellMeasurc voltage between PrimaryHO2S (Sensor 1) 8P connector ter-minals No. l and No.2.
ls there morethan 5 V?
Repair opon in the wi.o bEtwoonthe HO2S.nd G101 (located atth.rmonat housingl.
ls there more than 5 V?
Substitule a known-good ECM.nd .echeck. lt 3ymptom/indica-tion 906! rwry, roplace the origi-nal ECM,Check lor a short in the wire
{PO2SHTC line):1. Turn the ignition switch OFF.2. Disconnect ECM connector A(32P)trom the ECM.3. Check for continuity betweenECM connector terminal 46and body ground.
Ropair 3hort in tho wire betwoenthe ECM {46} and the Prim.ryHO2S lson3or 11.
Check for an open in the wire(PO2SHTC linel:Check for continuity betweenECM connector terminal 46 andthe Primary HO2S (Sensor 1)8Pconnector terminal No. 1.
Repair opsn in the wir6 botweenECM {A6} .nd the Primary HO2Slsonror 1).
Substituto a known-9ood ECMand rech6ck. lf symptom/indica-tion goes away, replace the origi-nal ECM.
Heated Oxygen Sensor (HO2S) Heater (Dl6Y5 engine with M/Tl (cont'd)
(From page 11-161)PRIMARY HO2S (SENSOR 1} 8P CONNECTOR {Cl45I
PO2SHTC{BtK/WHT)
PO2SHTCIALK/WHTI
ECM CONNECTOR
female terminals
11-162
\.
!
\
A {32P}
o
6I9l roIt
12t3l5t61't8t9a221 232a
252'2aEito,1| ---

The scan tool indicates Diagnostic Trouble Code (DTC) Pl167: A system malfunction in the Primary Heated
Orygen Sensor {Primary HO2S) (Sensor 1) Heater circuit
PRIMABY HO2S ISENSOR 1} 8P CONNECTOR
tc145l
ECM CONNECTOR C (31P)
- The MIL has be€n reported on.- DTC Pl167 i3 3tored.
Problem Veritication:1. Do the ECM Reset Procedure.
2. Start the engine. Hold the
engine at 3,000 mm with no
load (transmission in neutral)
until the radiator fan comes
on.Intormittont failure, system i3 OK
at thia time. Chock for Poor con_
noction3 or looso wilgt ai Cl45(Primary HO2S, Son3or 1l andECM.
ls DTC1167 indicated?
Check lor sn open in the wire(VS+ linel: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 betwe€n thePrimary HO2S (Sensor '1) 8P
connector terminal No 6 and
body ground.
Ch.ck the ECM:Measure voltage between the
ECM connector terminsl C25 and
body ground.
ls there more than 5 V?
Repair opon in the wite ECM (C25)
and P m.ry HO2S (S€n3or 11.ls there more than 5 V?
Replaco the Primary HO2S (Son-
sor 11.Substitute ! known-good ECM
and r6check. lf symptom/indica-tion gos6 away, r.place tho origi'
nd ECM,
,l23458910
111213t415161718
a2125a30
VS+{WHTIWire side of femaleterminals
1 1-163

PGM-FI System
Random Misfire
lFoioo l*u o, [FTioo l*' *' and
The scan tool indicates Diagnostic Trouble Code (DTC)
P0300*5 or P1300*3 *1 and some of P0301 - P0304:Random misfire.Description
Misfire detection is accomplished by monitoring the crankshaft speed with the crankshaft speed fluctuation (CKF) sensorwhich is attached to the crankshaft.
lf misfiring strong enough to damage the catalyst is detected. the MIL will blink during the time of its occurrence, and DTCP0300*5 or P1300*3'*' and some of DTCs P0301 through P0304 will be stored. Then, after misfire has ceased, the MIL willcome on.
lf misfiring that increases emissions is detected during two consecutive driving cycles, the MIL will come on, and DTCP0300*5 or P1300*3 *a and some of DTCS P0301 through P0304 will be stored.NOTE: lf some of the DTCS listed below are stored at the same time as a misfire DTC. troubleshoot those DTCS first, thenrecheck for the misfire DTC.
P0106*4. P0107. P0108, P1128*3 *5, Pl129*3 *5; MAP sensorP0131. P0132: HO2S
P0171, P0112i Fuel metering
P0401, P 1491, P1498: EGR svstem*1P0505: ldle Control SystemP1253: VTEC System*,P1361, P1362: TDC sensorP1381, Pl382: CYP sensorP1508: IAC valve
Possible Cause. Fuel pump insufficient fuel pressure, amount of flow. Fuel line clogging, blockage, leakage. Fuel filter clogging. Fuel pressure regulator stuck open. EGR system malfunction*1. Distributormalfunction. lgnition coil wire open. leakage *l: D16Y5 engine. lgnition control module malfunction *2: D16Y5, D16Y8, Bt6A2 engine. MAP sensor range/performance, poor response*r *3: '97 models. Valves carbon deposit *4;'96 models. Compression low *5: '98 - 00 models. IAC valve malfunctionr.. VTEC system malfunction*,. Fuel does not meet Owner's Manual spec., lackoffuel. HO2S. HO2S circuit
Troubleshooting
By test-driving, determine the conditions during which misfire occurs, Depending on these conditions, test in the orderdescribed in the table below.
Possible
- --^ ---
rage
causeEGR*1
system
Crankshaft
position (CKP)
sensor
Fuel
pressure
Distributor and
lgnition wirestcMClearance
tAc
ValveMAP
sensor
section 611-230,
231section 23section 23section 611-19411
Only low rpm and
loado@@oo
Only accelerating@o@@
Only high rpm and
toaooo@
Not specificoo@
NOTE: lf misfire doesn't recur, some possible causes are fuel that doesn't meet owne/s manualspec, lack of fuel, carbon deposits on spark plug, etc.
1 1-1 66
I
P0304

I
Misfire Detected in One Cylinder
P0301 | The scan tool indicates Diagnostic Trouble Code (DTC) P0301: Cylinder 1 misfire detected.
[F03O2l 16"""untool indicates Diagnostic Trouble code (DTc) P0302: Cylinder2 misfire detected.
[FO3Ofl 16" ".un toot indicates Diagnostic Troubte Code (DTC) P0303; Cylinder 3 misfire detected.
I P0304 I ths..rr tool indicates Diagnostic Trouble Code (DTC) PO3O4: Cylinder 4 misfire detected.
D€scription
lMisfire detection is accomplished by monitoring the crankshaft speed with the crankshaft speed fluctuation (CKF) sensor
which is attached to the crankshaft,
lf misfiring strong enough to damage the catalyst is detected, the MIL will blink during the time of its occurrence, and DTC
PO3O1, P0302, PO3O3 or P0304 will be stored. Then, after the misfire has ceased, the MIL will come on.
lf misfiring that increases emissions is detected during two consecutive driving cyclss, the MIL will come on, and DTC
P0301, P0302, P0303 or P0304 will be stored.
NOTE: lf some of the DTCS listed below are stored at the same time as a misfire DTC, troubleshoot those DTCS first, then
recheck for the misfire DTC.
PO106*1, P0107, P0108. P1128*3'*5, P1129*3'*5: MAP sensor
P0131, P0132: HO2S
P0171, P0172iFuel suppiy system
P0335, P0336: CKF sensor
P0401. P1491, P1498: EGR system
P0441: EVAP system Insufficient purge flow*6
Pl359. P1361. Pl362: TDC sensor
P1381. Pl382: CYP sensor*o: '96 models*6: '96 D16Y5 engine,'96 D16Y/ engine,'96 D16Y8 engine {sedan),'97 D16Y5 engine,'97 D16\4, engine (coupe: KA,
KC models, sedan KA. KC, KL (DX) models, hatchback:all models),'97 D16Y8 engine (sedan: KA, KC models)
Possible Cause
. Fuel injector clogging, fuel leakage, air leakage
. Fuel injector circuit open or shorted
. Spark plug carbon deposits, fouling, malfunction
. lgnition wires open. leaking
. Distributor malfunction
. ComDression low
. Valve clearance out of spec
. VTEC system malfunction (D16Y5, D16Y8. 81642 engine)
. HO2S
. HO2S circuit
(cont'd)
11-167
r'a

PGM-FI System
Knock Sensor (KSl ('96 - 98 D16Y5 engine with CW and'96 - 98 D16Y8
engine)
Forr-l I,3,.""""
tool indicates Diagnostic Trouble Code (DTC) P0325: A malfunction in the circuit of the Knock sensor
DIAPHRAGM
ECM/PCM CONNECTOR D {16PI
KS 2P CONNECTOR (Cl371
KS(RED/BLUI
KSIRED/BLU)
The MIL has bgen roportsd on.DTC PO:t25 is stored.
Problom veiilication:1. Do the ECM/PCM Reset Proce-oure,2. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator tan comes on,then let it idle.3. Hold the engine at 3,000 -
4,000 rpm tor at least 60 sec-onds.
Intermittenl fsilu16, 3y3l6m b OKat thi3 timg lteat drivo mav banoc63saryl.Chock tor poor conneclioni orloose wire3 b€twccn C137 {knocklen3or (KS)l and ECM/PCM.
ls DTC P0325 indicated?
Check for a short in tho wire {KSlinel:1. Turn the ignition switch OFF.2. Disconnect the knock sensor2P connector,3. Discon n ect the ECM/PCMconnector O (16P).
4. Check for continuity betweenECM/PCM connector termi-nals D6 and body ground.
Reo.ir 3hort in the wire betweenECM/PCM {DG) .nd knock 3.n-
Chock for an open in the wire(KS linel:Check for continuity betweenECM/PCM connector torminal D6and knock sensor 2P connectorterminal No. l.
Ropair open in the wire bgtweonECM/PCM lD6l and knock sen-3('t.ls there continuity?
Substitute a known-good knocksensor and recheck.
Rsplace th. o.igin.l knock s€nsor.
Substitute a known-good ECM/PCM end recheck. lf 3ymptom/indication goes rway, replacerhe original ECM/PCM.
Wire side of female terminals
1\
I
tert
,_-
eslnini
,--tl
le oI temrlsal€
121
189't01t12
13l4t5t6
11-170