1998 HONDA CIVIC diagnostic trouble code

PGM-FI System
Throttle Position ITP) Sensor ('96 - 98 Models,'99 - 00 D16Y5 engine with M/Tl
The scan tool indicates Diagnostic Trouble Code (DTC) P0122: A low voltage problem in the Throttle Position(TP) sensor circuit.
The TP Sensor is a potentiometer. lt is connected to the throttle valve shaft. As the throttle position changes, the throttleposition sensor varies the voltage signal to the ECM/PCM.
OUTPUT VOLTAGE IVI
1
2
1
0
s{i2(GRN/BLKI
THROTTLEOPENING
FULLTHROTTLE
TP SENSOR 3P CONNECTOR ICllOI
vocz(YEL/BLUI
Wire side ot femal6 terminals
ECM/PCM CONNECTOR D IT6PI
SG2 IGRN/ALKI
{To page l1-133)
Terminal side of male terminals
11-132
- Tho MIL h63 boon roportod on.- DTC m122 i. storcd.
Probl6m voritic€tion:1. Turn the ignition switch ON (ll).
2. Check the throttle positionwith the scan tool.
ls there approx. .49 V whenthe throttle is fully closed andapprox. 4.5 V when the throttleis lully op6ned?
Int..mittent tailura, rFiem ir OKat thit tima. Chock tor Door con-nections or loorc wires !t C110ITP lonrorl .nd ECM/FCM.
Ch6ck lor rn opon in the wire(VCC2linel:
1. Turn the ignition switch OFF.2. Disconnect ths TP sensor 3Pconnector.3. Turn the ignition switch ON lll).4, Measure voltage betweenthe TP sensor 3P conn€ctor ter-minals No. l and No.3.
ls there approx. 5 V?
Check for rn opcn in wire IVCC2line):Measure voltage between ECM/PCM conneclor terminals D10 and011.Chock for rn open or 3hort in TPlon30t:1. Turn the ignition switch OFF.2. At the s€nsor side, measureresistance between the TP sen-sor terminals No. 1 and No. 2with the throttle fully closed.
Roplir op€n in thg wiro batwcsnECM/PCM {DlO) rnd TP ren3or.ls there approx.5 V?
Substitut6 r known-good ECM/PCM and rach6ck. lf pro$ribodvohrge i! now avrilablc, replac€tho o.iginel €CM/FCM.
Wire side of female terminals

PGM-FI System
Throttle Position (TP) Sensor (€6 - 98 Models, 39 - 00 D16Y5 engine with M/T)
The scan tool indicates Diagnostic Trouble Code (DTC) P0123: A high voltage problem in the Throttle Position(TP) sensor circuit.
TP SENSOR 3P CONNECTOR IC1lOI
sG2IGRN/BLKIvcc2{YEL/BLUI
Wire side of female terminals
ECM/PCM CONNECTOR D (16P)
SG2 (GRN/BLKI
Wire side of female terminals
1 1-136
The MIL has been reportod on.DTC P0123 is sto.ed.
Problom veritication:1. Turn the ignition switch ON {ll).2. Check the throttle positionwith the scan tool.
ls there approx. 10% when thethrottle is fully closed andapprox. 90o/o when the throttleis lully opened?
Intermittont tailuro, system is OKat thb timo, Check for ooor con-nociion3 or loos6 wiros at C110ffP s€nsor) and ECM/PCM.
Chgck to. an opan in the TP son-sot:1. Turn the ignition switch OFF.2. Disconnect the TP sensor 3Pconnector.3. Turn the ignition switch ON (ll).
4. At the harness side, measurevoltage between tho TP sensor3P connecter terminals No, 1and No.3.
ls there approx.5 V?
Ch.ck tor .n open in the wira(SG2 linel:Measure voltage between ECM/PCM connector terminals D10 andD11.
Repair op6n in the wire betwoenECM/PCM (D11) rnd TP s6nsor.ls there approx. 5 V?
Substitute a known-good ECM/PCM snd rech.ck. lf pra3cribed
voltago is now available, replscetho original ECM/PCM,

I
Throttle Position (TP) Sensor ('99 - 00 Models except D16Y5 engine with M/Tl
The scan tool indicates Diagnostic Trouble Code {DTC) P0123: A high voltage problem in the Throftle Position
{TP) sensor circuit.
TP SENSOR 3P CONNECTOR {C11OI
sG2{GRN/BLKIvoc2
{YEUBLU}
'l'Wire side of female term;nals
ECM/PCM CONNECTOR C (31PI
Wire side of femal€ terminals
(cont'd)
11-137
The MIL has been reported on
DTC P0123 is slored.
Problem verification:1. Start the engine. Hold the
engine at 3,000 rpm with no
load (in Park or neutral) until
the radiator fan comes on
then turn the ignition swatch
OFF,2. Turn the;gnition switch ON (ll).
3. Check the throttle Positionwith the scan tool.
lntormittenl tailure, 3ystom is OK
at this time. Check tor Poor con'
neqtions or loo3€ wires at C'110(TP sensorl tnd ECM/PCM.
ls there approx. 10% when the
throttle is fully closed and
approx. 90% when the throttleis fully opened?
Ch€ck for an open in the TP s6n-
soJ:1. Turn the ignition switch OFF.
2. Disconnect the TP sensor 3P
3. Turn the ignition switch ON (ll).
4. At the wire harness side, mea-
sure voltage between the TP
sensor 3P connector terminalsNo. 1 and No.3.
ls there approx. 5 V?
Check tor an open in the wire(SG2lino):
Measure voltage between ECM/
PCM connector C (31Pi terminals
C18 and C28.
Repair open in the wite betwe€nECM/PCM (Cl81and TP son.or.ls there approx. 5 V?
Substitute a known-good ECM/PCM and recheck. lf Pr$cribedvoltage is now aveilabl6. replacethe original ECM/PCM.

PGM-FI System
Throttle Position (TP) Sensor (cont'd)
- The MIL hss been.eported on.- DIC P1121 i. stored.
Problem vedficatiod:1. Turn the ignition switch ON (ll).
2. Check the throttle position
with the scan tool.
ls TP *% or higher indicatedwhen the throftle is tullyopenod?
Intermittent tailure, ryttem i! OKrtthistimo.
I Pl 121 | The sca n tool indicates Diag nostic Trouble Code (DTC) Pl 121: Throttle Position (TP) lower than expected.
*: 11.8 {D16Y5 enginei12.9 {016Y7 engine)12.2 (D16Y8 engine)13.7 (816A2 engine)
I P1122 I The scan tool indicates Diagnostic Trouble Code (DTC) P1122: Throttle Position (TP) higherthan expected.
*: 16.5 {Dl6Y5, Dl6Y8 engine}16.9 (D16Y7 engine)16.5 (81642 engine)
- The MIL ha3 be6n repoJted on.- DTC Pl122 i. llorod.
P.oblom v6dfication:1. Turn the ignition switch ON (ll).
2. Check the throttle position
with the scan tool.
ls TP'70 or l€ss indicated whenthe throttle is fully closed?Intormitt6ot frilu.o, aFtom b OKat thb timo.
1 1-138

Primary Heated Oxygen Sensor {Primary HO2SI (Sensor 1)
t('96 - 98 Models except Dl6Y5 engine with M/Tl
The Heated Oxygen Sensor (HO2S) detects the oxygen content in the exhaust gas and signals the ECM/PCM. In operation,
the ECM/PCM receives the sjgnals from the sensor and varies the duration during which fuel is injected To stabilize the
sensor,s output, the sensor has an internal heater. The Primary HO2S (Sensor 1) is installed in the exhaust manifold.
HO2S:
VOLTAGE {VI
The scan tool indicates Diagnostic Trouble Code (DTC) P0131; A low voltage
Oxygen Sensor (H02S) (Sensor 1) circuit.
R|cH-AIR- - LEANFUELRANO
problem in the Primary Heated
SENSOR
ztRcoNlA
The MIL has be€n teported on.DTC P0131 is siorcd.
Problom verificalion:1. Do the ECM/PCM Reset Pro'
cedure.2. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on,3. Test-drive with the A/T in Eposition (M/T in 4th gear)
4. Check the Primary HO2S(Sensor 1) output voltage with
the scan tool during accelera-
tion using wide open throttle.
lntcrmift€nt failura, 3Y3tem is OKat this tims. Check for Poor con-nections or loo3e wi.o3 at C123(Primlry HO2S, 3sn3or 1) and
ECM/PCM,
(To page 1I-140)
{cont'd)
1 1-139

Primary Heated Oxygen Sensor (Primary- Fjq?S) (Sensor 1l
('99 - 0b Models exiept D16Y5 engine with M/T)
TheHeatedoxygensensors(Ho2S)detecttheoxygencontentintheexhaustgasandsigna|stheEcM/PcM'|noperation,
the EcM/pcM receives the signars from the sensor and varies the duration during which fuel is injected. To stabilize the
sensor,soutput,thesensornasaninternaIheater.ThePrimaryHo2S(sensorl)isinsta|ledinexhaustmanifo|d(D16Y8.
81642 engine: exhaust PiPe A)
SENSORTERMINALSVOLTAG€ (VI
HEATERTERMINALS
The scan tool indicates Diagnostic Trouble Code (DTC) P0131: A low voltage
Oxygen Sensor (HO2S) (Sensor 1) circuit
RICH+ AIR- - LEANFUELRATIO
problem in the Primary Heated
HEATER
- The MIL has been t€Ported on.- DTC P013'l is stored.
Problem veritication:1. Do the ECM/PCM Reset Pro-
2. Start the engine. Hold the
engine at 3,000 rpm wrth no
load (in Park or neutral) until
the radiator fan comes on
3. Check the PrimarY HO2S
lSensor 1) output voltage wath
the scan tool during accelera
tion using wide open throttle
lntermittont f.ilure, 3ystem i3 OK
at thi3 time. Check tor Poor con'
nections or loose wires el C123
{Primary HO2S, Sensor 1) and
ECM/PCM.
Does the voltage stay at 0 5 v
or less?
Check the fuel pressLlre (see Page11,109).
(To page 11 142)(cont'd)
11-141

Primary Heated Oxygen Sensor (Primary HO2SI (Sensor 1)
('96 - 9b Models except Dl6Y5 engine with M/Tl
PHO29IWHT}
The scan tool indicates Diagnostic Trouble Code (DTC) P0132: A high voltage problem in the Primary Heated
Oxygen Sensor (Primary H02S) (Sensor'l) circuit.
PRIMARY HO2S (Sonso. 'll 4P CONNECToR
tc123t
sG2IGRN/BLKI
Wire side ot female terminals
ECM/PCM CONNECTOR D I16PI
JUMPER WIRE
PHO2S (WHT}SG2 IGRN/BLKI
Wire side of tem6le terminals
Probl€m verification:1. Do the ECM/PCM Reset Pro-
cedure.2. Start the engine. Hold the
engine at 3,000 rpm with no
load (in Park or neutral) until
the radiator fan comes on
3. Test-drive with the A/T in Eposition (M/T in 4th gear)
4. Check the PrimarY HO2S(Sensor 1) oLltPut voltage with
the scan tool during decelera'tion using completely closed
throttle.
Int.rmittont fiilur., system it OK
at thb timo. Chock for Poot con-
nections or loo3a wir63 at Cl23
lPrimarY HO2S, SensoJ 1l .nd
ECM/PCM.
Does the voltage stay at 1.0 V
or more?
Check for an open in the Primary
HO2S:1. Turn the ignition switch OFF.
2. Disconnect the Primary HO2S(Sensor 1) 4P connector'
3. Connect the PrimarY HO25
lSensor l) 4P connector termi-
nals No. 1 and No. 2 with a
4. Turn the ignition switch ON (ll).
5. Check the PrimarY H02S(Sensor 1i outPut voltage with
the scan tool.
lsthere 1.0 V or more?
Check for an open in the wiro
{PHO2S line):1. Turn the ignition switch OFF.
2. Connect EcM/PcM connector
terminals D7 and D11 with ajumper wrre,3. Turn the ignition switch ON lll)4. Check the PrimarY HO2S(Sensor 1) output voltage withthe scan tool,
Replir open in tho wirc b€twccnECM/PCM lo?) and Prim!.Y
HO2S lsonsor 1).ls there 1.0 V or more?
Substitute a known-good ECM/PCM and recheck. lf 3ymptom/indicetion goos awey, roplacethe oliginal ECM/PCM.
11-143

PGM-FI System
Primary Heated Oxygen Sensor (Primary HO2SI (Sensor 1)
('99 - 00 Models except D16Y5 engine with M/T)
The scan tool indicates Diagnostic Trouble Code (DTC) P0132: A high voltage problem in the primary HeatedOxygen Sensor (Primary HO2S) {Sensor I ) circuit.
PRIMARY HO2S ls€n3or 1' 4PCONNECTOR(c123t
PHO2SIWHTI
Wire side of temale terminals
ECM/PCM CONNECTOR C 131PI
sG2(GRN/
BLK)
SG2 IGRN/8LK}
Ware side of female terminals
The MIL has been reported on.OTCP0132 is stored.
Problem vorificalion:1. Do the ECM/PCM Reset Procedure,Start the engine. Hold theengane at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on.Check the Primary HO25{Sensor lioutput voltage withthe scan tool during decelera-taon using completely closedthrottle.
Intermittent tailure, systom k OKat this time. Chock tor poor con-nections or looso wir* at Cl23(Primaly HO2S, Sonsor 1) andECM/PCM.
Check lor an open in the PrimaryH02S:1. Turn the ignition switch OFF.2. Disconnect the Primary HO2SlSensor 1)connector.3. Connect the Primary H02S(Sensor 1)4P connector terminals No. 1 and No. 2 with a
4. Turn the ignition switch ON (ll).5. Check the Primary H02S{Sensor l) output voltage withthe scan tool.
ls there 1.5 V or more?
Check lor an open in th€ wire(PHO25 lin€l:1. Turn the ignition switch OFF.2. Connect ECM/PCM connectorterminals C16 and C18 with ajumper wire.3. Turn the ignition switch ON {lli.4. Check the Primary HO2S(Sensor 1i output voltage withthe scan tool,
Roptir op.n in tho wire betweonECM/PCM lCl6l and Prim.ryHO2S lsensor 11.
ls there 1.5 V or more?
Subsiitute a known-good ECM/PCM and r.check. lf symptom/indication goos away, replecethe original ECM/PCM.
11-144