2002 HONDA CIVIC main relay

Cruise Control
Symptom Troubleshooting Index
NOTE:' The numbers in the table showthetroubleshooting sequence.. Before troubleshooting.- check the No, 10 (7.5A) and No. 4 (10A) fuses in the under-dash fuse/relay box. and the No. 7 (15A) fuse in theunder-hood fuse/relay box,- check that the horn sounds.- check the tachometer to see if it works properly.- check the speedometer lo see if it works properly.
SymptomDiagnostic procedureAlso check forCruise control cannot be
set
1. Check main switch (see page 4-42)
2. Check SET/RESUME/CANCEL switch (see page 4-42)
3. Test brake pedal position switch (see page 22-84) and checkits adjustment {see page 19,6)
4. Test clutch pedal position switch (see page 4-45) and check
its adjustment (see page 12-41
5. Check cruise control unit {see page 4-40}
6. Check vehicle speed sensor (VSS) (see page 22-65)
. Poor ground:
G501. Open circuit,
loose or
disconnected
term inals:
LT GRN,
BLI(ORN.
GRY/RED, BLU.
LT BLU,
BLUAA/HTCruise control can be set
but indicator light does
not go on
1. Check cruise control indicator bulb in gauge assembly {seepage 22-631
2. Check cruise control unit (see page 4-40)
. Poor ground:
G501. Open circuit,
loose or
disconnected
termrnats:
YEL, BLUA/ELar, 'i.a c^aa.l ic
noticeably higher or
lower than what was set
1. Check vehicle speed sensor (VSS) {see page 22-65)
Check cruise control actuator {see page 4-43)
2. Check cruise control unit (see page 4-40)
Excessive overshooting
or undershooting when
trying to set speed
1. Check cruise control actuator (see page 4-43)
2. Check vehicle speed sensor (VSS) (see page 22-65)
Check cruise control unit (see page 4-40)
3.
Speed fluctuation on a
flat road with cruise
control set
1. Check vehicle speed sensor (VSS) (see page 22-65)
Check cruise control actuator (see page 4-43)
2. Check cruise control unit (see page 4-40)
Vehicle does not
decelerate or accelerate
accordingly when SET/
RESUME/CANCEL button
is pushed
1. Check SET/RESU ME/CANCEL switch (see page 4-42)2. Check cruise control unit {see page 4-40)
Open circuit, loose
or disconnected
terminals:
GRY/RED,
LT GRN/BLKSet speed does not
cancel (engine rpm stays
high) when clutch pedal
is pushed
1. Testclutch pedal position switch (see page 4-45) and checkits adjustment (see page 12-4)
2. Check cruise control unit (see page 4-40)
Short to ground in
the LT BLU wire
Set speed does not
cancel when brake pedal
is pushed
'1. Test brake pedal position switch (see page 22-84) and checkits adjustment (see page 19-6)
2. Check cruise control unit (see page 4-40)
Open circuit, loose
or disconnected
terminals:
WHT/BLK
4-38
g,

Cruise Gontrol
Cruise Control Unit Input Test
SRS components are located in this area. Reviewthe SRS component locations (see page 23-'13) and precautions andprocedures (see page 23-14) in the SRS section before performing repairs or service.
1. Disconnect the 14P connector from the control unit.
2. Inspect the connector and socket terminals to be sure they are all making good contact.
. lf the terminals are bent, loose, orcorroded, repairthem as necessary, and recheckthe system.. lf the terminals look OK, go to step 3.
Wire side offemale terminals
3. With the 14P connector disconnected, make these inDut tests.
CavityWireTest conditionTest: Desired resultPossiblecause ifresuh is not obtained
BRN/WHTConnect battery
power
Check the operation of the
magnetic clutch: Clutch
should click and output link
should be locked.
' Faulty actuator. Poor ground (G301)
. An open in the wire. Shon to ground (arcs when
Dower is connected)
2BLUlgnition switch ON(ll), main swltch ON
and brake pedal
pressed, then
reteaseo
Check for voltage to ground;
There should be 0 V with lhe
pedal pressed and battery
voltage with the pedal
released.
. Faulty brake pedal position
switch. An open in the wire. Open in cruise control main
swrtcn. Blown No. 4 (10 A)fuse in the
under/dash fuse/relav box
3BLKUnder all conditionsCheck for continuity to
grouno:
There should be continuitv
. Poor ground (G501)
. An open in the wire
BLIVORNlgnition switch ON
flr)
Check for voltage to ground:
There should be battery
vottaqe.
Blown No. 4 (10 A)fuse in the
under-dash f use/relay box
An oDen in the wire
5WHT/BLKBrake pedal pressed,
then released
Check for voltage to ground:
There should be battery
voltage with the pedal
pressed, and 0 V with thepedal released.
Blown No. 7 {15 A) fuse in the
under-hood fuse/relay box
Faulty brake pedal position
SWIICN
An oDen in the wire
4-40

CavityWireTest conditionTest: Desired resultPossible cause il result is not obtained
6GRYiREDSet button pushedCheck for voltage to ground:
There should be battery
voltage,
When testing terminal No.6,
there should be no voltage on
terminal No. 7.
Blown No.7 (15 A)fuse in the
under-hood fuse/relay box
Faulty horn relay
Faulty sevresume/cancel
swrtch
Faulty cable reel
An open in the wire
Shon to ground (horn sounds
when button is pressed)
7LT GRN/
BLK
Resume button
pusneo
Check for voltage to ground:
There should be battery
voltage.
When testing terminal No.7,
there should be no voltage on
terminal No. 6.
BRNConnect battery
power to the BRN
terminal and ground
to the BRNIVEL
termrnal
Check the operation of the
actuator motor: You should
be able to hear the motor.
. Faulty actuator. An open in the wire11BRNI/EL
10B LUIVE Llgnition switch ON
0r)
Attach to groundi
Cruise indicator light in the
gauge assembly should come
on.
Blown No. 10 (7.5 A) fuse in
the under-dash fuse/relay box
Blown cruise indicator bulfl
Faulty gauge assembly
An open in the wire
12BLU/VVHTlgnition switch ON
(ll) and main switch
ON; raise the front of
the vehicle, and
rotate one wheel
slowly while holding
the other wheel
Check for voltage between
thE BLU/VVHT (+) ANd BLK
( )terminals:
Thereshouldbe0 5Vor
more repeatedly.
Faulty VSS
An open in the wire
Short to ground
13LT GRNlgnition switch oN
{ll) and main switch
ON
Check for voltage to ground:
There should be battery
voltage.
Blown No. 4 (10 A)fuse in the
under-dash fuse/relay box
Faulty main switch
An oDen in the wire
14LT BLUClutch pedal
reteaseo
Check for continuity to
grouno:
There should be continuity.
NOTE:There should be no
continuity when the clutch
oedal is Dressed.
Faulty clutch pedal position
swtlcn
Poor ground (G501)
Incorrect clutch switch
adjustment
An open in the wire
lf any test indicates a problem, find and correct the cause, then recheck the system. lf all the input tests prove OK,
the cruise control unit may be faulty. Substitute a known-good cruise control unit and retest. lf the system works
properly, replace the cruise control unit.
4-41

Fuel and Emissions Systems
System Descriptions (cont'dl
ECM lnputs and Outputs at Connector E (31P}
L
u
1iMoFPR
2sr-{]zs3LG34SG3
6$1025HTC
1M RLY
8AFSHTCR
I
14FTP15ELD
16EPSLD
18ACC20Z/VBS21VSV
22BKSW23K-LINE24SEFMJ26NEP
21rMoCD
29scs30WEN31MIL
Wire side of female terminals
NOTE: Standard battery voltage is '12 V.
TerminalnumberWire colorferminal nameDescription Signal
GRNI/ELIMO FPR (IMMOBILIZERFLJEL PUMP RELAYIDrives PGM Fl main relay 20Vfor2 seconds after turning ignition switch ON{ll). then batterv voltaoe2WHT/REDSHO2S (SECONDARYHEATED OXYGEN SENSOR(SECONDARY HO2S),SENSOR 2r
Detects secondary HO2S{sensor 2) signalWith throttle Jully opened from idle with fullywarmed up engine: above 0.6VWith throttle quickly closed: below 0.4 V
3BRN/YELLG3 (LOGIC GROUND)cround forthe ECM/PCMcontrolcircuitLess than 1.0 V at all times
4PNKSG3 {SENSOR GBOUND)Sensor oroundLess than 1.0 V at all times5YEUELUVCC3 {SENSOR VOLTAGE)Provides sensor voltageWith ignition switch ON (ll): about 5 VWith ionition switch OFF: about 0 V6BLKATr'HTSO25HTC (SECONDARYHEATED OXYGEN SENSOR(SECONDARY H02S)HEATER CONTROL)
Drives secondary HO2SheaterWith ignition switch ON (ll): baftery voltageWilh fullv warmed up engine running: dul,controlled
1REDA/ELMRLY (PGM.FI MAINRELAY}Drives PGM-Flmain relay 1Power source forthe DTCWith ignition switch ON (ll): about 0 VWith ignition switch OFF: battery voltage
IORNAFSHTCR {AIR FUEL BATIO(Iy'F)SENSOR HEATERCONTROL RELAY)
Drives air fuel ratio sensorheater relayWith ignition swirch ON {ll): 0 V
IYEUBLKIGl (IGNITION SIGNAL)Detecrs ignition signalWith ignition switch ON (ll): battery voltageWith iqnition switch OFF: about 0 V't4LT GRNFIP lFUEL TANKPRESSURE (FTP) SENSOR)Detects FTP sensor signalWith ignition switch ON (ll) and fuel fill cap open:about 2.5 VGRN/REDELD (ELECTRICAL LOADDETECTOF)Detects ELD signalWith ignition swjtch ON itt):aOoutO.t V l-gV(deDendino on electrical load)LT GRN/8LKEPSLD (ELECIRICALPOWEB STEEBING LOADDETECT)
Detects Power steering loadsrgnalAt idle with steering wheel in straight aheadposition: about 0 VAt idle with steering wheelatfull lock: momentary
'18REDACC (Ay'C CLUTCH RELAY)Drives P,/C clutch relayWith compressor ON: about 0 VWith comoressor OFF: batterv voltaoe
11-22
\-

Fuel and Emissions Systems
(
{
System Descriptions (cont'd)
ldle Control System
When the engine is cold, the Ay'C compressor is on, the
transmission is in gear, the brake pedal is pressed. thepower steering load is high, or the alternator is
charging, the ECIM controls current to the ldle Air
Control (lAC) valve to maintain the correct idle speed.
Refer to the System Diagram to see the functional
layout of the system.
Brake Pedal Position Switch
The brake pedal position switch signals the ECM when
the brake pedal is oressed.
Electrical Power Steering (EPS) Senser
The EPS sensor signals the ECM when the power
steering load is high.
ldle Air Control llACl Valve
To maintain the proper idle speed, the IAC valve
changes the amount of air bypassing the throttle body
in response to an electrical signal from the ECM.
From AIR To INTAKECLEANER MANIFOLD
IAC VALVE
11-32
Fuel Supply System
Fuel Cut-off Control
During deceleration with the throttle valve closed,
current to the injectors is cut off to improve fuel
economy at engine speeds over 1,030 rpm. Fuel cut-off
action also occurs when engine speed exceeds
6,900 rpm, regardless of the position of the throttle
valve, to protect the engine from over-rewing. When
the vehicle is stopped. the ECM cuts the fuel at engine
speeds over 6,500 rpm.
Fuel Pump Control
When the ignition is turned on, the ECM grounds the
PGM-Fl main relay which feeds current to the fuel pump
for 2 seconds to pressurize the fuel system, With the
engine running. the ECM grounds the PGM-Fl main
relay and feeds current to the fuel pump. When the
engine is not running and the ignition is on, the ECI\4
cuts ground to the PGM-Fl main relay which cuts
current to the fuel pump.
PGM-FI Main Relay 1 and 2
The PGM-Fl main relay consists of two separate relays.
Relay 1 is energized whenever the ignition switch is ON(ll) to supply battery voltage to the ECM power to the
injectors, and power for relay, Relay 2 is energized to
supply power to the fuel pump for 2 seconds when the
ignition switch is turned ON (ll), and when the engine is
runnrng.

Fuel and Emissions Systems
System Descriptions (cont'dl
ldle Control System Diagram
The idle speed of the engine is controlled by the ldle Air Control (lAC) varve:
'Aftertheenginestarts,theIACvalveopensforacertainamountoftime.Theamountofairisincreasedtoraisethe
idle sDeed.. When the engine coolant temperature is low, the IAC valve is opened to obtain the proper fast idle speed. Theamount of bypassed air is controlled in relation to engine coolant temperature.
INTAKE MANIFOLDIAC VALVEAKE AIR DUCT
CLEANER
\
BLK/REO
YEL/BLK ---< FromPGM.FIMAINRELAY
THROTTLE AODY
Intake Air System Diagram
This system supplies air for engine needs. A resonator in the intake air
drawn into the svstem.
VARIOUSSENSOnS
pipe provides additional silencing as air is
THROTTLE AODYVARIOUSSENSORS
BLK
BLK
I
11-36
{

'}
DATA LINK CONNECTOR IDLCIGeneral Troubleshooting Information, page 1 l 3
PGM.FI MAIN RELAY 1Troubleshooting, page 1 1-97
ENGINE CONTROL MODULEGeneral Troubleshootin g Information,page 11 3Troubleshooting, page I 1-96
11-51

PGM-FI System
a
I
DTC Troubleshooting (cont'dl
45. Measure voltage between injector 2P connector
terminal No. 1 and body ground.
INJECTOR 2P CONNECTOR
tll-z]
,o, ,"=rrrr*, -lt-
oI
Wire side of female terminals
ls there battery voltage?
YES-Go to step 46.
NO-Repair open in the wire between the injector
and the PGM-Fl main relay l.l
Turn the ignition switch OFF.
Check for continuity between body ground and
ECM connector terminal (see table).
46.
47.
ECM CONNECTOR B {24P)
Wire side of female terminals
ls there continuity?
YES-Repair short in the wire between the ECM
and the ;njector.I
NO-Go to step 48.
PROBLEM
CYLINDER
DTCECM
TERMINAL
WIRE
COLOR
No. 1P030'1B5BRN
No.2P0302B4RED
No.3P0303B3BLU
No. 4P030482YEL
11-76
48. Connect injector 2P co nnector term inal No.2 to
body ground with a jumper wire {see table).
INJECTOR 2P CONNECTOR
Wire side of {emale terminals
49. Check for continuity between body ground and
ECM connector terminal (see table).
ECM CONNECTOR B I24P)
Wire side oJ temale terminals
ls therc continuity?
YES Replace the injector, then recheck.l
NO Repair open in the wire between the ECM and
the injector.I
tll-Z-l-]_r-l_rNJ
IJUMPER
IwrBE
PROBLEM
CYLINDER
DTCWIRE COLOR
No. 1P0301BRN
No.2P0302RED
No. 3P0303BLU
No. 4P0304YEL
PROBLEM
CYLINDER
DTCECM
TERMINAL
WIRE
COLOR
No. 1P0301B5BRN
No. 2P0302B4RED
No. 3P0303B3BLU
No. 4P030482YEL