1999 HONDA CIVIC HO2S

System Description
Electrical Connections ('99 - 00 Models except Dl6Y5 engine with M/Tl
(cont'd)
T:I
1
0
EVAP PURGE CONTROLSoLENOtOVAIVEc26 ECTECTSENSOR
D
EVAP COI{TROL CANISIE R
IATSENSOR
ta-t
c25 tAT
HO2S(sENSoFt
EVAP BYPASS SOI.ENOID VALVE
cl Po2s{tc"Eso! 87
)wEGF coNTRoL solENoro vaLvE'"c16PHO2S
vlsBr2VTEC SOLEr{O|D VATVE
H02SiSENSOR 2),wA23 SHO2S
VTECPFESSUFESWITCH
sEt{soR
-t,.1 f
I
BRAKE SWITCH
c7 sG1
SENSOB(Buln l oF
@E
lfil
*_r
/V | GAUGE
* lassEMBLIIl-
SPEEOSENSOR
tr
D5VBSOLo4tND A14
N DTI
NC DTOSPEEDSENSOR
LS+ Bl7UNEAR SOLENOID VALVET'I AT?04LS- a3
LOCIPr. l03alP03LCA 01P CONTBOISOIENOiDVALVE BLCB 03IOI{IROL SOLENOID VAIV€ A
SHIFI COTITROL SOLENOID VALVE BSHE D2
POStTtON
t----
I
To IIIT!FLOCK CONTROL UNIT
--t
L
l-
I
I
11-40
-.._.._.._.._l
,'-J

llo2s (sENsoR t
SECONOARYHO2S (SENSOR 2)
I- wrrzneo'f15151FCA ,a[HT -] f- IFELWWHI.- FFi/v\^- IF ETJVWrfT'--I l+ |
HO2S (gENSOR 2)
\-
11-43

Troubleshooting
Troubleshooting Procedures (cont,dl
ECM/PCM Data
By connecting the OBD ll scan tool or the Honda pGM Tester to the l6p data link connector (DLC), various data can beretrieved from the EcM/PcM. The items Iisted in the table below conform to the sAE recommended practice.The Honda PGM Tester also reads data beyond that recommended bv SAE.understanding this data wil help to find the causes of intermittent fairures or engine probrems,
NOTE:
' The "operating values" given below are approximate values and may be different depending on the environment andthe individual vehicle.. Unless noted otherwise, "at idle speed,, means idling with the engine completely warmed up, Ay'T in position @ or E],M/T in neutral, and the Ay'C and all accessories turned off.
(
DataDescriptionOperating ValueFreeze Data
Diagnostic
Trouble Code(DTC)
lf the ECM /PCM detects a problem, it will store it as acode consisting of one letter and four numbers.Depending on the problem, an SAE-defined code (poxxx)or a Honda-defined code (Plxxx) will be outDut to therester.
lf no problem is detected,
there is no output.
YES
Engine SpeedThe ECM/PCM computes engine speed from the signalssent from the Crankshaft Position sensor.This data is used for determining the time and amount offuel injection,
Nearly the same as
tachometer indication.YES
Vehicle SpeedThe ECM/PCM converts pulse signals from the VehicleSpeed Sensor (VSS) into speed data.Nearly the same as
speedometer indicationYES
Manifold
Absolute
Pressure {MAP)
The absolute pressure caused in the intake manifold bvengine load and speed.With engine stopped:
Nearly the same as atmo-
spheflc pressure
At idle speed:
24 - 31 kPa (180 - 280
mmHg, 7.1 - 11.0 inHg)
YES
Engine Coolant
Temperature
(ECT)
The ECT sensor converts coolant temperature into volt_age and signals the ECM/PCM. The sensor is a thermistorwhose internal resistance changes with coolant temDera_ture. The ECM/PCM uses the voltage signals from theECT sensor to determine the amount of iniected fuel.
With cold engine:
Same as ambient temper,
ature and IAT
With engine warmed up:
176 - 194.F (80 - 90.C)
YES
Heated Oxygen
Sensor {HO2S)(Primary,
Sensor 1)(Secondary
Sensor 2)
The Heated Oxygen Sensor detects the oxygen contentin the exhaust gas and sends voltage signals to theECI\4/PCM. Based on these signats, the ECM/pCM con_trols the airlfuel ratio. When the oxygen content is high(that is, when the ratio is leaner than the stoichiometricratio), the voltage signal is lower.When the oxygen content is low (that is, when the ratiois richer than the stoichiometric ratio), the voltage signalis higher.
0.0 - 1.25 V
At idle speed:
about 0.1 - 0.9 V
NO(Sensor 1)
1 1-86

DataDescriotion
Loop status is indicated as "open" or "closed"'
Closed: Based on the HO2S output, the ECM/PCM deter-
mines the airlfuel ratio and controls the amount of inject-
ed fuel.
Open: lgnoring HO2S output, the ECM/PCM refers to sig-
nals from the TP, MAP, and ECT sensors to control the
amount of injected fuel.
The air/fuel ratio correction coefficient for correcting the
amount ot injected fuel when H02S feedback is in the
closed loop status When the signal from the HO2S is
weak, short term fuel trim gets higher, and the ECM/PCM
increases the amount of injected fuel The airlfuel ratio
gradually gets richer, causing a higher HO2S output
Consequently, the short term fuel trim is lowered, and
the ECMiPCM reduces the amount of injected fuel
This cvcle keeps the airlfuel ratio close to the stoichio-
metric ratio when in closed loop status'
Operating ValueF eeza Data
HO2S
Feedback
Loop Status
At idle speed: closed
YES
Short Term
Fuel Trim
! 20%
YES
Long Term
Fuel Trim
Long term fuel trim is computed from shon term fuel
trim and indicates changes occurring in the fuel supply
svstem over a long Period
lf long term fuel trim is higher than 1.00, the amount of
injecGd fuel must be increased. lf it is lower than 1 00'
the amount of injected fuel must be reduced'
! 20%
YES
lntake Air
Temperature
{IAT)
The IAT sensor converts intake air temperature into volt-
age and signals the ECM/PCM. When intake air tempera-
ture is low, the internal resistance of the sensor
increases. and the voltaqe signal is higher'
With cold engine:
Same as ambient temPer'
ature and ECTYES
At idle speed:
approx. 10 %YESThrottle
Position
Based on the accelerator pedal position, the open'ng
angle of the throttle valve is indicated
lgnition
Timing
lgnition timing is the ignition advance angle set by the
gCV/eCV. tn" gCU/PCM matches ignition timing to the
driving conditions.
CLV is the engine load calculated from the MAP data'
At idle speed: 12'i 2'
(81642 engine: 16" t 2")
BTDC with the SCS ser-
vice connector connected.
NO
Calculated
Load Value
{CLV)
At idle speed:
15-35%
At 2.500 rpm with no load:
12 - 30%
YES
ro
11-87

Troubleshooting
Engine/P_o_wgrtrain Control Module Terminal Arrangement('96 - 98 Models '99 - 00 Dt6y5 engine with M/T) tc'oniOi
ECM/PCM CONNECTOR C {31PI
1
CKFP
2
CXPPTDCPa
ACS
5
sTs
7
scsII
rMA
10
v8u121314t51517
ALTF
TE
vss23lP+
21252930
TMA
Wire side of female terminalsECM/PCM CONNECTOR C (31PI
NOTE: Standard baftery voltage is 12 V
'1: USA modelr2rA,.T (D16Y7, O16Y8 ensane)*3: CVT (O16Y5 engine)*4: Ay'T and O16Y7 engine'5: Excepl A./T snd Dl6Y7 engine16: Ay'T (D16Y8 ensine){7: CVT (Dl6Y5 eosine) and O16Y8 enoine"8: 96 Dl6Y8 engine (coupe),'97 D16y8 engine (coupe: atl:ed-9I t!!rnodelr,'98 D16y5 ensine,,98 D16y8 e;sine.D16Y5 lM/T) ensine
1-90
19: D16Y5 engine'10: M/T (Dl6Y5 engine)*11r Except M/T 116Y5 engine)*12: D16Y5, D16Y8 engine*13: Dl6Y8 enqine*14: O16Y7 enginei15: '-97 O16Y7 engjne (coupe: KL modet, sedan: KL (LX) modet),'98D16Y7 enqine'99 - 00
1
To.min!lnumberWiracoloaTorminalnameDo6criptlonSignal
1BLU/REDCKFP (CKF SENSOR P SIDE)Detects CKF sensor.With engine running: pulses2BLUCKPP (CKP SENSOF PSIDE)Detects CKP sensor.With engine running: pulses3GRNTDCP {TDC SENSOR PSIDE}Detects TDC sensor,With engine running: putses4YELCYPP (CYP SENSOR P SIDE)Detects CYP sensor.With engine running: pulses
5BLU/FEDACS {Tr'C SWITCH SIGNAL)Detects ,ay'C sw;tch signat.With Iy'C switch ONr 0 VWith Ay'C switch OFF: batrery vottage
6BLU/ORNSTS (STARTER SWITCHSIGNAL)Detects staner swilch signal,With staner switch ON ltlt): batery vohageWith staner switch OFF: 0 V
8RNSCS (SERVICE CHECKSIGNAL)Detects service check connector signal{the signalcausing a OTC indicationlWith the connector connected: O Vwith the connector disconnected: about 5 vor battery voltageLT 8LUK,LINE (DLC)Sends and receives scan iool signal,Wirh ignition switch ON { ): about 5 V
9+3GRYDat6 communication with TCM: ECMcontrol ctat6 outputWith ignition switch ON (tt):putses
10WHT/BLUVBU (VOLTAGE BACK UP)Power source forthe ECM/PCMcontrol circuit. Power sourc€ lortheDTC memory
Battery voltage at all times
11WHT/REDCKFM {CKF SENSOR MSIDE)Ground tor CKF sensor signal.
12CKPM (CKP SENSOR MSIDE)Ground for CKP sensor s;gnat.
REDTDCI\4 (TDC SENSOR MSIDE)Ground for TDC sensor signal.
14BLKCYPM (CKP SENSOB MSIDE}Groond for CYP sensor signal.
15."BLU/BLKVTM (VTEC PRESSUREswtTcH)Oetscts VTEC pressure switch signal.Wrth engine at low enginespeed:0 VWth engineathigh engine speed: tatteryvoltase
16GRN
PSPSW (P/S OIL PRESSUREswtTcH)Detects PSP switch signal.At idle with steering wheel in straight aheadposition:0 VAt idle with stsering wheet at fult tock batteryvoltage'17WHT/REDALTF (ALTERNATOR FRSIGNAL)Detects ahernator FR signal.With fullyw6rmed up engine running:0 V- bat-teryvohage (depending on electricat toad)18BLUI/VHTVSS {VEHICLE SPEED SEN-SOR}Oetects VSS signal.Whh ignitjon switch ON {tt) and front wheetsrotating: cycles 0 V- 5 V23+14BLKlP+ {HO2S PUtr4P CELL +}Controls HO2S pump ce .With ignition switch ON (ll): abour 0.5 - 5.3 V
24.10REDrP-, vs- {Ho2s coMt oN)Reference voltage supply.With fullywarmed up engine et idle:about2.6-2.8 V25*roVS+ (VS CELL VOLTAGE)Detects VS cell voltage.With ignition switch ON t): abour 7 V
29LT GRN*'ATPNP (Ar'T GEAR POSI,TroN swrTcH)Deteds Ay'T g6srposhion switch signat.In E orE position: O Vln any other position: battery vottage
RED{roCLSW (CLUTCH SWITCH}Detects clutch switch signal,Wilh clutch pedal released: about 5 VWith clutch pedal deDressed: O V30PNK4TMBData communication with TCM:ECM controldata inputWith ignit;on switch ON (lt):putses

ECM/PCM CONNECTOR D I16P)
Wire side ot female terminals
ECM/PCM CONNECTOR D l16P)NOTE: Standard battery voltage is 12 V
Te.minalnumb€r
Wirecolor
Terminaln!meDor.riptionSignal
RED/BLKTPS (THROTTLE POSITION
SENSOR}
Detects TP sensor signal.With throttle fully open: about 4.8 V
With throttle fully closedl about 0.5 V
REDA/VHTECT {ENGINE COOLANTTEMPERATURE SENSORDetects ECT sensor signalWith ignition switch ON{ll): about 0.1 - 4 8 v
(depending on engine coolant lempe ratu re)
3RED/G RNMAP {MANIFOLD ABSO'LUTE PRESSURE SENSOR}Detects MAP sensor signal.With ignition switch ON(ll): about 3 V
At idle: about 1.0 V
{depending on engine speed)
YEUREDVCCl (SENSOR VOLTAGE)Power source lor MAP sensor.With ignition switch ON (ll): about 5 v
With ignition switch OFF: 0 V
5GRNMHTBKSW {BRAKE SWITCHIDetects brake switch signalWith brake pedal released: 0 v
With brake pedal depressed: baftery voltage
6*?RED/BLUKS {KNOCK SENSOR}Detects KS signal.With engine knocking: Pulses
1
PHO2S (PRIMARY HEAT-ED OXYGEN SENSOR,SENSOR 1)
Detects Primary heated oxygen
sensor (sensor 1l signal
With throttle fullv opened from idle with
Iully warmod up engine: above 0.6 V
With throttle quickly closed: below 0.4 v
LABELDetects LABEL resistanceWith engine r!nning:about 0.3 - 4.9 V
8RED//ELIAT (INTAKE AIR TEM-PERATURE SENSOR)
Detects IAT sensor signal.With ignition switch ON (ll): about 0 1 -
4.8 V {depending on intake air temperature)
9*lWHT/BLKEGRL iEGR VALVE LIFT
SENSOR)
Detects EGR valve lift sensor signalAt idle without vacuum: about'1 2 V
With 27 kPa (2OO mmHg,8 in. Hg): about 4 3 V
10YEUBLUVCC2 (SENSOR VOLTAGE)Provides sensor voltage,With ignition switch ON(ll): about 5 V
With ignition switch OFF:0 V
11GRN/BLKSG2 (SENSOR GROUND}Sensor ground.Less than 1.0 V at alltimes
12G RN,4/1r'HTSG1 (SENSOR GROUND)Ground for MAP sensor.Less than 1.0 V at alltimes
GRN/BLK*1?SHO25G (SECONDARY
HEATED OXYGEN SEN'
SOR, SENSOR 2 GROUND)
Ground for secondary heated oxy-
gen sensor (sensor 2).
14WHT/REDSH02S (SECONDARY
HEATED OXYGEN SEN'soR, sENsoR 2)
Detects secondary heated oxygen
sensor (sensor 2) signal.With throftle fully opened lrom idle with
fully warmed up engine: above 0.6 V
With throttle quickly closed: below 0.4 V
15|3. *15LT GRNPTANK {FUEL TANK PRES.
SURE SENSOR)
Detects fueltank prgssure sensor'With fuelfill caD opened: about 2.5 V
16*1GRN/RED
EL (ELD)Detects ELD signal.With parking lights turned on at idle: about
2.5 - 3.5 VWith low beam headlights turned on at
idle: about 1.5 - 2.5 V
*1: USA model*2r A/T (D16Y7, D16Y8 engine)*3: CVT (D16Y5 engane)*4: A,/T and Dl6Y7 engine*5: Except A/T and D16Y7 engine*6: A"/T (D16Y8 engine)i7: CVT (Dl6Y5 engine) and Dl6Y8 engine*8: .96 D16Y8 engine (coupei,'97 D16Y8 engine
models, sedanr KL model),'98 016Y5 engine,
engine, '99 - 00 D16Y5 (M/T) engine
*9: D16Y5 engine*10: M/T (D16Y5 engine)*11: Except M/T (Dl6Y5 engine)* 12r D16Y5. D16YB engine*13: D16Y8 engine*14: Dl6W engine*15: '97 D16Y7 engine (coupe: KL model, sedan: KL lLX) model),'98D16Y7 engine:(coupe: all'98 D16Y8
(cont'd)
1 1-91

Diagnostic Trouble Code (DTCI Chart
connector is connecteda1: Dl6Y5 engine (CVT)*2: Except D16Y5 engine (M/T)*14:'97 model*15:'96 model*16: '98 model
(cont'd)
11-97
DTC
{MlL indication*lDelection liemProbable CausePage
Manifold Absolute
Pressure Circuit
Range/Performance Problem
. Vacuu m connection. MAP sensor11115
P0107 (3)
Manifold Absolute
Pressure Circuit
Low Input
Open or short in MAP sensor circuit
MAP sensor
ECMiPCM
TCM*1
11't1'l
P0108 (3)Manifold Absolute
Pressure Circuit
High Input
Open in MAP sensor circuit
MAP sensor
ECtvt/PCM
't 1 121
P0.111*14. *15 (10)
lntake Air Temperature
Circuit
Range/Performance Problem
. IAT sensor11-124
PO112 {10}
Intake Air
Temperature Circuit
Low Input
Short in IAT sensor circuit
IAT sensor
ECMiPCM
11-125
P0113 (10)lntake Air
Temperature Circuit
High Input
Open in IAT sensor circuit
IAT sensor
ECM/PCM
't1-126
P0116 (86)Engine Coolant
Temperature Circuit
Range/Performance Problem
. ECT sensor. Cooling system11-124
PO't't7 {6)
Engine Coolant
Temperature Circuit
Low Input
Short in ECT sensor circuit
ECT sensor
ECM/PCM
11-129
P0118 (6)Engine Coolant
Temperature Circuit
High lnput
Open in ECT sensor circuit
ECT sensor
ECM/PCM
11-130
?0122 t1l
Throttle Position
CircuitLow Input
Open or short in TP sensor circuit
TP sensorECM/PCM
TCM*1
11-132
P0123 (7)Throttle Position
Circuit
High Input
Open in TP sensor circuit
TP sensor
ECM/PClvl
11-136
P0131*' (1)
Primary Heated Oxygen Sensor
Circuit Low Voltage(Sensor 1)
Short in Primary HO2S (Sensorl ) circuit
Primary HO2S {Sensor 1)
Fuel supply system
ECM/PCM
1 1-139
P0132*' ('r)
Primary Heated Oxygen Sensor
Circuit High Voltage(Sensor 1)
Open in Primary HO2S {Sensor 1} circuit
Primary HO2S (Sensor 1)
ECM/PCM
1 1- 143
P0133*' (61)
Primary Heated Oxygen Sensor
Slow Response(Sensor 1)
. Primary HO2S (Sensorl). Exhaust system11-145
P0135*? (41)
Primary Heated Oxygen
Sensor Heater
Circuit Malfunction(Sensor 1)
. Open or short in Primary HO2S(Sensor 1) heater circuit. ECM11-151
*: The DTCS in parenthesis will be indicated by the blinking of the Malfunction Indicator Lamp (MlL) when the SCS service
! ta

Troubleshooting
DTClMlL indicationlDatection hsmProbablo CausePage
P0137(63)Secondary Heated Oxygen SensorCircuit Low Voltage(Sensor 2)
Short in Secondary HO2S lSensor 2) circuitSecondary H02S {Sensor 2)ECM/PCI\41 1-153
P0r38 {63)Secondary Heated Oxygen SensorCircuit High Voltage(Sensor 2)
Open in Secondary HO2S (Sensor 2) circuitSecondary HO2S (Sensor 2)EC[I/PCM11-154
P0'139 (63)Secondary Heated Orygen SensorSlow Response(Sensor 2)
Secondary H02S lSensor 2)1l-156
P0141 (65)
Secondary Heated Oxygen SensorHeaterCircuit Malfunction(Sensor 2)
. Open or short in Secondary HO2S (Sensor2) heater circuit. ECM/PCM11-157
P0171 (45)
System Too LeanFuel supply systemPrimary HO2S (Sensor 1)MAP sensorContaminated fuelValve clearanceExhaust leakage
11,164
P0172 (45)
System Too RichFuel supply systemPrimary HO2S (sensor l)MAP sensorContaminated fuelValve clearance
11-164
P0300*16' }l?
andsome ofPo3o1 /r'' \P0302 l72lP0303 l73lP0304 \7 4l
Random Misfirelgnition systemFuel supply systemMAP sensorEGR systemIAC valveContaminated fuelLack of fuel
r1-r66
P0301P0302P0303P0304
/rt\172ll73l\7 4l
- Cylinder 1- Cylinder 2- Cylinder 3- Cylinder 4Misfire Detected
Fuel InjectorFuel Injector circuitlgnition systemLow compressionValve clearance
11 167
P0325*3 (23)Knock Sensor (KS) CircuitMalfunctionOpen or short in Knock Sensor (KS) circuitKnock Sensor {KS)ECM/FCtvl11-170
P0335(4)Crankshaft PositionSensor CircuitMalfunction
Crankshaft Position SensorCrankshaft Position Sensor circuitECM/PCM11-172
P0336(4)Crankshaft PositionSensorRange/Performance
. Crankshaft Position Sensor. Timing belt skipped teeth11-172
P040'r*r (80)Exhaust GasRecirculationInsufficient Flow Detected
' EGR valve. EGR line
P0420(67)Catalyst SystemEfficiency BelowThreshold
. Th.ee Way Catalytic converter. Secondary HO2S11 253
Diagnostic Trouble Code (DTCI Chat (cont'dl
*3: D16Y5 engine (CVT), D16Y8 engine and B1642 engine*4: D'16Y5 engine*16: '98 model+17: '99 - 00 models
,Jla
1 1-98