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
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
Troubleshooting
Diagnostic Trouble Code (DTGI Chart (cont'dl
*7: D16YS engine (M/T)*8: D16Y5, D'16Y8 engine*9: USA model*14r'97 model*15r '96 model
DTC(MlL indicationlDetection lt6mProbablc CausePage
P1162+1 (48)Primary Heated Oxygen Sensor(Sensor 1) CircuitMalfunction
Open or short in Primarv HO2S (Sensor 1Primary H02S (Sensor 1)1 1- 146
P]163' (61)Primary Heated Oxygen Sensor(Sensor '1) CircuitSlow Response
. Primary HO2S (Sensor 1)
11-145
Pl164*r (61)Primary Heated Oxygen Sensor(Sensor l) Cjrcuit Range/Performance Problem
. Primary HO2S (Sensor 1)
1 1- 150
P1165*? (61)Primary Heated Oxygen Sensor(Sensor 1) Circuit Range/Performance Problem
. Primary HO2S (Sensor 1)
11-150
P1166' (41i
Primary Heated Oxygen Sensor(Sensor '1) Heater System ElectricalProblem
Open or short in Primary HO2S (Sensor 1)heater circuitPrimary HO2S (Sensor 1)ECM/PCM
1 1-'161
P1167*' (41)Primary Heated Oxygen SensorlSensor 1) Heater SystemMalfunction
Open in Primary HO2S (Sensor 1) VS+ circuitPrimary HO2S (Sensor 1) HeaterPrimarv HO2S {Sensor 1)1 1- 163
P1168*' (48)Primary Heated Oxygen Sensor(Sensor 1) LABEL Low Input
. Short in Primary HO2S (Sensor 1) LABELcircuit11-151
Pl169*? (48)
Primary Heated Oxygen Sensor(Sensor 1)IABEL High Input. Open in Primary HO2S (Sensor 1)IABELcircuit. Short in ground circuit11.152
P1259*3(221
WEC System MalfunctionWEC Solenoid ValveOpen or short in WEC SolenoidValve circu itVTEC Pressure SwitchOpen or short in VTEC Pressure SwitchcircuitECM,FCM
Section 6
P1297*s (20)Electrical LoadDetector CircuitLow Input
Electrical Load DetectorElectrical Load Detector circuitECM/PCM11-179
Pr298+' l20l
Electrical LoadDetector CircuitHigh Input
Electrical Load DetectorElectrical Load Detector circuitECM/PCM1 1-181
anosome ofP0301P0302P0303P0304
l71ll72ll73ll7 4l
Bandom Misfirelgnition systemFuel supply systemMAP sensorEGR systemIAC valveContaminated fuelLack ol fuel
11-166
1 1-100
Troubleshooting
Diagnostic Trouble Code (DTCI Ghart (cont'd)
DTClMlL indicationlDetegtion homProbablo CsussPage
P1491*! \12J
EGR ValveLift InsufficientDetected
EGR valve (with lift sensor)EGR valve lift sensor circuitEGR control solenoid valve (A,/I)
EGR control solenoid valve circuitEGR lineEGR valve circuit (M/T)
ECM
't1-256
P1498*. 112)
EGR ValveLift SensorHigh Voltage
EGR valve (with lift sensor)EGR valve lift sensor circuitECM11-265
Pl508*10 (14)
ldle Air Control ValveCircuit FailureIAC valveIAC valve circuitECM
'11-194
{14)
ldle Air Control ValveCircuit FailureOpen or short in IAC valve circuitIAC valveECM/PCM1l-198
P1607 1-)
Engine ControlModule/Powertrain Control lvlodulelnternalCircuit Failure A
. ECM/PCM
11-188
P1655*1 (30)TMA,/TMB Signal Line FailureODen or sho.t in TMA,/TMB circuit11-189
P1705P1706P 1753P1758P1768P1785P1790P1791P1793 (70)*
P1870P1873P1879P1885P1886P1888P1890P1891
Automatic Transaxle
Section 14
*: The E indicator light and the Malfunction Indicator Lamp {MlL) may come on simultaneously.*4: D16Y5 engine (M/T)+10: Except A/T and Dl6Y7 engine*11: A,/T and D16Y7 engine*18: D16Y5 engine (CW) (except '99 - 00 models)
11-102
How to Read Flowcharts
A flowchart is designed to be used from start to final repair. lt's like a map showing you the shortest distance. But beware:
lf you go off the "map" anywhere but a "stop" symbol, you can easily get lost.
tSrARTl(bold type)
FanoNl
@
tsroP I
{bold type)
Describes the conditions or situation to start a troubleshooting flowchart.
Asks you to do something; perform a test, set up a condition etc.
Asks you about the result of an action, then sends you in the appropriate troubleshooting direction.
The end of a series of actions and decisions. describes a final repair action and sometimes directs you to
an earlier part of the flowchart to confirm your repair,
NOTE:
. The term "lntermittent Failure" is used in these charts, lt simply means a system may have had a failure. but it checks
out OK at this time. lf the Malfunction Indicator Lamp (MlL) on the dash does not come on, check for poor connections
or loose wires at all connectors related to the circuit that you are troubleshooting (see illustration below)'
. Most of the troubleshooting flowcharts have you reset the Engine Control Moduls (ECM)/Powertrain Control Module
(pCM) and try to duplicate the Diagnostic Trouble Code (DTC). lf the problem is intermittent and you can't duplicate the
code, do not continue though the flowchart. To do so will only result in confusion and, possibly, a needlessly replaced
ECM/PCM.
. ,,Open" and "Short" are common electrical terms. An open is a break in a wire or at a connection. A short is an acci-
dental connection of a wire to ground or to another wire. In simple electronics, this usually means something won't
work at all. In complex electronics (like ECM's/PCM'sl. this can sometim€s mean something works, but not the way it's
suDDosed to.
toosE
1 1-103
PGM-FI System
Engine Control Module/Powertrain Control Module (ECM/PCMI
('96 - 98 Models,'99 - 00 Dl6Y5 engine with M/Tl (cont'd)
NOTE:. When there is oo Diagnostic Trouble Code (DTC) stored, the MtL wi
stay on if the SCSservace connector is connected and the ignition switch is on,. lf this symptom is intermittent, checklor:- A loose Fl E/M 115 A) fuse in the under hood luse/relay box- A loose No. 13 FUEL PUMP fuse (15 A) in the underdash fuse/relay box- An intermittent shon in the wire between the ECM/PCM (C7) and the service cnecKconnector- An intermittent short in the wire between the ECM/PCM (A18) and the gaugeassembly- An intermittent shon in the wire between the ECM/PCM {D4) and the MAp sensorAn intermittent short in the wire between the ECM/PCM (D10), the Tp sensor, theEGR valve l:ft sensor (D16Y5 engine) and/or the Fuel tank pressure sensor (,96Dl6Y8 engine (coupe), '97 016Y7 engine (coupe: KL model, sedan: KL (LX) modeli,'97 016Y8 engine {coupe: all models, sedan: KL modeti,'98,all models}- PGM-FImain relay. See the OBD ll scan tool or Honda PGM Tester user's manuals lor specitic operatinginstructions.
ECM/PCM CONNECTOR C 13lPI
Wire side of female terminals
(To page 11 109)
(To page 11,109)
11-108
The Maltunction Indicator Lamp(MlLl stays on o. comes on eftartwo s€conds,
Check the Oiagnoslic TroubleCode {DTC}I1. Connect a scan tool or HondaPGM Tester.2. Turn the ignition switch ON (ll).
3. Read the DTC with the scantool or Honda PGM Tester.
Go to troubleshooting p.oc€dur€s(se€ pago 11{11.Are any DTC{s) indicated?
Check the DTC by MIL indication:1. Turn the ignition switch OFF.2. Connect the SCS service con,nector to the service checkconnector.3. Turn the ignition switch ON (lli.
Repair opon ol short in wirebotwoen the ECM/PCM (C8)
and Data Link Connector.Go to troublelhooting proce-dure ls6e page 11-811.
Does the MIL indicate any DTC?
Try to start the engine.
Does the engine start?
Check for a short in the wire(SCS lin€l:1. Disconnect the SCS serviceconnector.2. Stop the engine and turn theignition switch ON {lli.3. Measure voltage between theECM/PCM connector terminalC7 and body ground.
Ropair short to body Iround inthe wire betweon ECM/PCM lCTland sorvice check connector.
ls there approx. 5 V?
scs tBRNI
Engine Control Module/Powertrain Control Module (ECM/PCM)
('95 - 00 Models except Dl6Y5 engine with M/T)
NOTE:. When there is no Diagnostic Trouble Code lDTC) stored, the MIL will staY on if the SCS
seruice connector is connected and the ignition switch is on.. lf this symptom is intermittent, check for:- A loose No. 25 (METER) {7.5 A) fuse in the underdash fuse/relay box- A loose Fl E/M (15 Alluse in the undeFhood fuse/relay box- A loose No. 13 FUEL PUMPfuse (15 A) in the under-dash fuse/relay box- An intermittent shon in the wire between the ECM/PCM (A18) and the gauge assem'
- an intermittent short in the wire between the ECM/PCM (C19) and the MAP sensor- An intermittent short in the wire between the ECM/PCM {C28), the TP sensor, the
EGR valve lift sensor (D16Y5 engine) and/or the Fuel tank pressure sensor ('96 D16Y8
engine (coupe),'97 D16Y7 engine lcoupe: KL model, sodan: KL (LX) model)"g7
Dt6Y8 engine (coupe: all mod;ls, sedanl KL model),'98-all models,'99-al' models''00-all models.- PGM'FI main relay. See the oBD ll scan tool or Honda PGM Tester user's manuals for specific operating
instructrons,
ECM,/PCM CONNECTOR A I32PI
Wire side of {emale terminals
The Mrlfunction Indicator LamP{MlL) never comes on {even tor
two seconds) after ignition is
turned ON lll).
Turn the ignition switch ON lll).
- Repair shott or open in thowire bstwoon No. 25 IMETER)l?.5 A)tuse and gauga tsom_blv.- Reolace No. 25 (METERI (7.5
Alluse.
ls the low oil pressure light on?
Try to start the engine.
Check for an opon in the wire orbulb (MlL line):1. Turn the ignition switch OFF.2. Connect the ECM/PCM con'
nector terminal A18 to bodyground with a iumper wire.
3. Turn the ignition switch ON (ll)
Does the engine start?
- Repair open in tho wire3
betwoon ECM/PCM (A18) andgaugo .*tembly.- Rool.ce the MIL bulb.
Substitute a known-good ECM/
PCM and rochoc&. lf sYmptom/indication goes sw6y, repl.ce
tho original ECM/PCM.Turn the ignition switch OFF.Inspect Fl E/M (15 A)fuse in theunderhood Iuse/relay box.
Rop.ir short in the wirc
betwo€n Fl E/M (15 A) luso
and PGM-Fl mrin rGl.y.Reol.ce Fl E/M (15 A)tusa.
lnspect No. 13 FUEL PUMP {15 A}
luse in the under-dash fuse/relay
- Reoair short in the wiro
between No. 13 FUEL PUMP
115 Al luse sod PGM-FI mainrelay.- Reolace No. 13 FUEL PUMP115 A) tuse.
(To page 11 112)
(cont'd)
11-111
.f,