2003 HONDA CIVIC under-dash

\-
Starting System
Component Location Index
UNDER-DASHFUSE/RELAY BOX
CLUTCH INTERLOCK SWITCHTest, page 4-6
STARTERStaner Circuit Troubleshoot,ng, page 4 5Solenoid Test, page 4-7Performance Test, page 4-8Replacement, page 4-9Overhaul, page 4 '10
-l--
ar]]]ll -i I
-. -_- rt_.1
_-- _. /
Itti:
:-lt.i tit-!t:!|- -!t
STARTER CUT RELAYTest, page 22-51
\'l
\'\l I
r\, l,
,. /
\/'....",r.v
\:,...)
/'\tl \
4-3

Starter Circuit Troubleshooting
NOTE:. Airtemperature must be between 59'and 100'F (15'
and 38'C) during this procedure.
. After this test, or any subsequent repair, reset the
engine controle module (ECM) to clear any diagnostlc
trouble codes (DTCS) {see page 11-4).. The battery must be in good condition and fully
charged.. lf you disconnect the baftery, do the ECM idle learn
procedure (see page 11-139).
Recommended Procedure:. Use a starter system tester.. Connect and operate the equipment in accordance
with the manuf acturer's instructions.
Alternate Procedure
1. Hook up the following equipment:. Ammeter, 0 400 A. Voltmeter, 0 20 V (accurate within 0.1 volt). Tachometer,0 1200 rpm
2.Remove the No. 17 (15A) fuse from the under-dash
fuse/relay box.
With the clutch pedal pressed, turn the ignition
switch to start (lll).
Did the starter crank the engine normally?
YES-The starting system is OK.I
NO-Go to step 4.
3.
L
4-5
4. Check the battery condition. Check electrical
connections at the battery, the negative baftery
cable to body, the engine ground cables and the
starter for looseness and corrosion. Then try
starting the engine again.
Did the statter crank the engine?
YES Repairing the loose connection fixed the
problem. The starting system is now OK.!
NO lf starterwill notcranktheengine atall, goto
step 5. lf it cranks the engine erratically or too
slowly, go to step 7. lf it won't disengage from the
flywheel ring gear when you release the key, check
for the following until you find the cause.
. Solenoid plunger and switch malfunction. Dirty drive gear or damaged overrunning clutch
5. Make sure the transmission is in neutral, then
disconnect the starter subharness 1P connector (A)
from the engine wire harness 'lP connector (B).
Connect a jumper wire from the battery positive
terminal to the starter subharness 'l P connector.
Did the starter crank the engine?
YES-Go to step 6.
NO Check the BLK,ANHT wire between the starter
subharness 1P connector and the starter. lf wire is
OK, remove the starter, and repair or replace as
necessary.
(cont'd)

Starting System
Starter Circuit Troubleshooting
(cont'dl
6. Check the following items in the order listed untilyou find the open circuit.
. Check the BLIVWHT wire and connectors
between the under-dash fuse/relay box and theignition switch, and between the under-dash
fuse/relay box and the starter.. Check the ignition switch {see page 22-53).. Check the clutch interlock switch and connector.. Check the starter cut relay (see page 22-51).. Check LT GRN wire between the starter cut relayl
under-dash fuse/relay box and the clutch
interlock switch.. Check the BLK wire between the clutch interlock
switch and G501.
7, Check the cranking voltage and current draw.
ls ctanking voltage greatet than or equal to 8.7 V
and current draw less than or equal to 230 A?
YES-Go to step 8.
NO Replace the starter. or remove and
disassemble it, and check these items until you find
the cause.
. Starter armature dragging. Shorted armatu re winding. Excessive drag in engine
8. Check the engine speed while cranking the engine.
ls the engine speed above 100 tpm?
YES Go to step 9.
NO-Replace the starter, or remove and
disassemble it, and check for the following untilyou find the cause.
. Excessively worn starter brushes. Open circuit in commutator brushes. Open circuit in starter armature commutator
segments. Dirty or damaged helical splines or drive gear. Faulty drive gear clutch
9. Remove the starter, and inspect its drive gear andthe flywheel ring gear for damage. Replace anydamaged pans.I
4-6
Clutch Interlock Switch Test
1. Disconnect the clutch interlock switch 2P connector.
2. Remove the clutch interlock switch (A).
Check for continuity between the terminals
according to the table.
. lf the continuity is not as specified, replace the
clutch interlock switch.. lf OK, install clutch interlock switch and adjust
the pedal height (see page 12-4l..
Terminal
Cl","f ri"t.tf ."tS""*Jrl2
PRESSEDo--- --o
RELEASED

Gharging System
Charging Circuit Troubleshooting
lf the charging system indicator does not come on or
does not go off, or the battery is dead or low, test these
items in the order listed below:
Battery (see page 22-50)
Charging system indicator
Alternator and regulator circuit
Alternator control system
Charging System Indicator Test
1. Turn the ignition switch ON {ll).
Does the chatging system indicator come on?
YES Go to step 2.
NO Go to step 3.
2. Start the engine.
Does the charging system indicator go off?
YES-Charging system indicator circuit is OK. Go
to the Alternator and Regulator circuit Test. t
NO-Go to step 3.
3. Turn the ignition switch OFF.
4. Troubleshoot the multiplex control system (see
page 22 172).
ls the multiplex control system OK?
YES Go to step 5.
NO Check the multiplex control system as
indicated by the diagnostic trouble code (DTC) (see
step 8 on page 22-172).1
5. Disconnect the engine wire harness 6P connector
from the starter sub harness 6P connector.
4-22
\"4
6. Measure the voltage at the No. 3 terminal of the
engine wire harness 6P connector with the ignition
switch ON { ll).
ENGINE WIRE HARNESS 6P CONNECTOR
IBLK/YEL}
Wire side of female terminals
ls there battery voltage?
YES-Go to step 7.
NO-Check for a blown No.4 {10A) fuse in the
under-dash fuse/relay box. lf the fuse is OK, repair
open in the wire between the alternator and the
under-dash fuse/relay box. I
Turn the ignition switch OFF.
Disconnect engine control module (ECM) connector
B (24P).
Check continuity between the ECM connector
terminal B'10 and engine wire harness 6P connector
terminal No. 6.
?
7.
8.
9.
ACGL {WHT/BLU)
ENGINE WIBEHARNESS6PL (WHT/BLUI
Wire side of femaletermina s
ls there continuity?
YES Go to step 10.
NO-Repair open in the wire between the
alternator and the ECN4.I
ECM CONNECTOB A (24P)

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

Fan Gontrols
Radiator Fan Circuit Troubleshooting
1. Check the No. 4 (20A) fuse in the under-hood
fuse/relay box, and the No. 14 (10A) fuse in the
under-dash fuse/relay box.
ls the tuse (s) OK?
YES-Go to step 2.
NO- Replace the fuse (s) and recheck.l
2. Remove the radiator fan relay from the under-hood
fuse/relay box, and test it (see page 22-51).
ls the relay OK?
YES Go to step 3.
NO Replace the radiator fan relay. t
3. Measure the voltage between the No. 2 terminal of
the radiator fan relay 4P socket and body ground.
RADIATOR FAN RELAY 4P SOCKET
Terminal side of female terminals
ls there battery voltage?
YES Go to step 4.
NO Replace the under-hood fuse/relay box. I
10-14
\-
(
4. Connect the No. landNo.2terminalsofthe
radiator fan relay 4P socket with a jumper wire.
RADIATOR FAN RELAY 4P SOCKET
JUMPERWIRE
Terminal side of Iemale terminals
Does the radiatot fan run?
YES Go to step 5.
NO Go to step 6.
Disconnect the jumper, and turn the ignition switch
ON { ll}. Check for voltage between the No. 3
terminal of the radiator fan relay 4P socket and
body ground.
BADIATOB FAN RELAY 4P SOCKET
Termlnal side of female terminals
ls there battety voltage?
YES-Go to step 9.
NO Check for an open in the wire between the
under-hood fuse/relay box and under-dash fuse/
relay box.l
\-