VTEC Control System
Troubleshooting Flowchart
tFtrsrl #ilH:::lj1t:"J:T,?ffnostic
rrouble code (Drc) Pr25e: A probrem in the vrEc Pressure switch circuit or
Reter to page 1 l-38 th roug h 1 1-55 before trou bleshooting.
* Road Test:Accelerate in 1st gear to an engine speed over 3,000 rpm(D16Y5 engine) or 6,000 rpm (D'16Y8 engine).Hold that engine speed for at least two seconds.It DTC P1259 is not repeated during the first road test, repeatthis test two more tames.
VTEC PRESSURE SWITCH 2PCONNECTOR
Terminal side ofmale terminals
Wire sid6 ol femalerermtnats
VTM
l1 (BLu/BLK)
f;-) |I
I
Y
I
The MIL has been reoorted on.DTC P1259 is sto.ed.
Check the VTEC Cont.ol Syst6m:1. Do the engine control module(ECM)/powertrain control module lPCM) Reset Procedure (see
section 11).2. Stan the engine.3. Warm up the engine to normaloperating temperature (cool-
ing fan comes on).4. Do the Boad Test.*Intermittont tailura, 3y3t.m is OKat thia time.Check for ooor connoctionr o.loose wirea at VTEC oiassurclwitch, VTEC solonoid valvo .ndECM/PCM,
ls OTC P1259 indicated?
Test rhe VTEC Prensure Switch:1. Turn the ignition switch OFF.2. Disconnect the VTEC Pressureswitch 2P connector.3. Check for continuity betweenVTEC pressure switch 2P con-nector terminal No. 1 and No.2.
Replace the VTEC preasure 3witch.ls there continuity?
Te3t the VTEC Pressure SwitchWire:1. Turn the ignition switch ON lll).2. Measure the voltage betweenVTEC press u re switch 2Pconnector No. l and bodyground.
In3poct for en opon or shod toground in thG wi.. bctwoon thoVTEC pro$ur6 switch rnd ECM/PCM l'96 - 9a: C15,'99 - 00: C101.lf tha wiro i3 OK,3ubrtitute aknown-good ECM/PCM andrecheck.
ls there battery voltage?
{To page 6'4i
!
Fuel and Emrsslons
SoecialToofs .....,...."..,. 11-2
Component Locations
lndex ....................., ......... 11-3
Svstem Description
Vacuum Connections ................,,..,.. ......... 11-12
Electrical Connections ...............,.,.,... ....... 11-29
System Connectors ........,.,.,.......................... 1 1-51
Troubleshooting
Troubleshooting Procedures ................. .. 11-81
Engine Control Module/PowertrainControl Module TerminalAfiangement ....,.,..... 11-88
Diagnostic Trouble Code Chart .................,., 11.97
How to Read Flowcharts .,.......................... . 11-103
PGM-Fl System
System Description ...... 11-10,1
Troubleshooting Flowcharts
Engine Control Module/PowertrainContlol Module ........ 11-107
Manitold Absolute Pressure Sensor .....'. . ... 11-115
fntake Air Temperatuie Sensor ..... . . ., . 11'121
Engine Coolant Temperatuae Sensol ........., 11-128
Throttle Position Sensor ...................,........... 11-132
Primary Heated Orygen Sensor (Sensor 1l ... 11-139
Secondary Heated Oxygen Sensor(Sensor 21.................................................... 1 1-153
Heated Oxygen Sensor Heater ...................,. 11-157
Fuel Supply System ...... 11-164
Random Mislire ......., ..11-166
Misfire Detected in One Cylindsr ................. 11-167
Knock Sensor .,.,............ 11-170
CKP/TDC/CYP Sensor ................................... 11'172
Vehicle Speed Sensor ...........,......,...,.,........... 1t-176
Barometric Pressure Sensor ...............,......... I 1-178
Electrical Load Detector,.,,............................ 1 1-179
CKF Sensor .................... 11-183
ECM/PCM Internal Circuit ............................. I 1-188
A/T Signal {TMA/TMBI .................................. I 1-189
ldle Control System
System Doscriplion ............ 11-190
Troubleshooting Flowcharts
ldle Control System ...... 11-192
ldle Air Control Va1ve .................................... I 1-19i1
Starter Switch Signal .................................... 1 1'202
Air Conditioning Signal ................................. 11'201
Ahernator FR Signal .................................... . 1 1-208
BrakeSwitch Signal ..................................... f 1"210
Power Sleering Prossure Switch Signal ......11-212
A/T Gear Position Signal ............................... 11-216
Clutch Swiich Signal ................................-.... 11-214
ldte Speed Setting . .............11-220
Fuel Supply System
Fuel Lines .,...................,.,.,.,11-221
Fuef Tube/Ouick-Connect Fittings ..........,.,........ 11 -227
System Description ....'.... 11-230
Fuel Pressure .......,.,,........... 11-230
Fuef fniectors ......................11-232
Fu€f Pressure Regulator .....,.......................'...,. 11-231
Fuef Fifter ............................11-235
Fuel Pump .............'.......'.... 11-236
PGM-FI Main Relay .............11'237
Fuel Tank ................ ....,...'.'.' 11'211
Intake Air System
System Description ....-.-.....11-243
Air Cfeaner ...........,......."". .11-211
Throttle Cable .....................11-211
Throttfe Body ........ ..'... . . .,.11-211
Fuel Iniestion Air Control System ,.,.,....-........... 11-250
Emission Control System
System Description .-..........11-252
Taifpip€ Emission ...............11-252
Three Way Catafytic Convert€r ............,.,,.,.,.,.... 11 -252
Exhaust Gas Racirculaiion System ...,.,,,,.,.,.,.,,. 11'254
Positive Crankcas€ Ventilation System .... . . .. 11-266
Evaoorative Emission Controls ..................,,..,.,. 11 -267
I
CLUTCH SWITCH lDl6Y5 onginoM,/TITroubleshooting, page 1 1-218
'96 - 98 modsls:
Sell-diagnostic Procedures.page 11 81
ENGINC CONTROL MOOUI.T(FCMI/POWERTRATN
CONTROL MODULE IPCMITroubleshooting, page 1 1-107
'9!, - 0o modol3:
PGM.FI MAIN RELAYRslay Testing, page 11-237Troubleshooting, page 1 1-238PGM.FI MAIN RELAYRelay Testing, page l1 237Troubleshooting, pago 1'! 238
SERVICEl2Pl
CONNECTOR
ENGINE CONTROL MODU1T(ECM}/POWERTRAIN
CONTROL MODULE IPCMITroubleshooting, page 11 111SERVICE CHECK CONNECTORtzPlSelf-diagnostic Procedures,page 11-81
Self-diagnostic Procedures,page 11-81
{cont'd)
11-7
Troubleshooting
Troubleshooting Procedures
How To Begin Troubleshooting
When the Malfunction Indicator Lamp (MlL) has been reported on, or there is a driveability problem, use the appropr'-
ate orocedure below to diagnose and repair the problem'
A. When the MIL has come on:
,1. connect the Honda PGM Tester or an oBD ll scan tool to the 16P Data Link connector (DLC) located near the left
kick panel.
2. Turn the ignition switch ON (ll)
3. Check the DTC and note it. Also check and note
the freeze trame data
Refer to the Diagnostic Trouble Code Chart and
begin troubleshooting.
NOTE:
.SeetheoBD||scantoolorHondaPGMTesteruser,smanua|sforspecificoperatinginstructions..
.Thescantoo|oltestercanreadtheDiagnosticTroub|ecodes(DTc},freezeframedata,currentdata,andother
Engine Control Module (ECM)/Powertrain Control Module (PCM) data'
oFreezeframedataindicatestheengineconditionswhenthefirstma|function,misfireorfue|trimma|function
was detected. lt can be useful information when troubleshooting'
B. When the MIL has not come on , out there is a d riveability problem, refer to the Symptom Chart on page 1 1-84'
c.DTcswi|lbeindicatedbytheb|inkingoftheMa|function|ndicatorLamp(M|L)withthescsserviceconnectorcon.
nected.
Connect the SCS service connector to Service Check Connector as shown (The 2P Service Check Connector is
|ocatedunderthedashonthepassenger,ssideofthevehic|e')TurntheignitionswitchoN{||)'
OBO ll SCAN TOOL olHONOA PGM TESTER
SERVICE CHECKCONNECTOR I2P)
scs sERvlcE(cont'd)
MALFUNCTIONINDICATORLAMP
DATA LINK CONNECTOR Il6PI
07PAZ - (x)l0100
11-81
Troubleshooting
Troubleshooting Procedures (cont,dl
ll, Engine Control Module (ECM)/powertrain Control Module (pCM) Reset procedure
NoTE: Resetting the EcM/PcM will erase any stored DTcs and any freeze data. lt will also restart all readiness codemonitors.
Either of the following actions will reset the ECM/PCM.
. Use the OBD ll scan tool or Honda pGM Tester to clear the EClM,s/pCM,s memory.
NorE: see the oBD ll scan tool or Honda PGM Tester user's manuals for specific operating instructions.
' Turn the ignition switch oFF. Remove the BACK uP (7.5 A) fuse from the under-hood fuse/relay box for 10 sec-onds.
NorE: Bemoving the BACK uP (7 5 A) fuse cancels the clock and the radio presets. Make note of the customer,spresets so you can reset then
lll. Final Procedure (this procedure must be done after any troubleshoottng)
1. Remove the SCS Service Connector if it is connected.
NoTE: If the Scs service connector is connected and there are no DTcs stored in the EcMipcM, the MtL will stayon when the ignition switch is turned ON 0l).
2. Do the ECM/PCM Reset procedure.
3. Turn the ignition switch OFF.
1-82
Probable Cause List lFor th€ DTC Chart, see page 11-971*: '99 - 00 models
Probable GausePageSystem
11 1-107Engine Control Module (ECM)/Powertrain Control Module (l'uM)
PGM-Fl main relay
l^^iti^n cwetam
211-230,231
3't't-237
Section 23
51' 1-172,183Crankshaft Position/fop Dead Center/Cylinder Fosltlon sensor clrculr' Lr\F selrsor
circuit
Intake Air Temperature (lAT) sensor circuit
ldle Air Control (lAC) Valve
ldle speed adjustment
Throttle bodY
Throftle cable
Manifold Absolute Pressure (MAP) sensor
Throftle Position (TP) sensor
Barometric pressure (BARO) senso'
Mf g"a, po"ition signal (see page 11-216) or clutch switch signal
Brake switch signal
Air Cleaner
lntake air pipe
Three Way Catalytic Converter (TWC)
Evaporative emission (EVAP) control
Contaminated fuel
ORVR vent shut valvs
't1-124
71 1-194
I11-220 - 223
11-241
'1011-244
1111-115
1211-132
13't1-178
14Section 14. 11-218
1511-210
16't1-244
1811-252
1911-261
20
21*11-296
(cont'd)
11-85
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