2003 HONDA CIVIC relay

Component Location Index
UNDER.HOODFUSE/RELAY BOX
EPS CONTROL UNITEPS Control Unit Removal/lnstallation,page 17 -67
UNDER.DASH FUSE/RELAY BOX
-,'/.,....
'.,i,
X ]
DATA LINK CONNECTOR I16P)
TOROUE SENSOR
STEERING GEARBOXSteering Gearbox Removal, page 17-51Steering Gearbox Overhaul, page 17-55Steering Gearbox Installation, page 17-63
Removal/lnstallation,page l7-49
GAUGE ASSEMBLY
MOTOR
17-17

EPS Components
DTC Troubleshooting Index
DTCDetection ltemNote
DTC; 12A problem with voltage for torque sensor T/SlG(see page 17-28)
DTC: 16A problem with average of voltage for torque sensor VT3 and VT6(see page 17-29)
DTC: 17A problem with the voltage for torque sensor 12 V power source Vcc 1(see page 17-31)
DTC: 18A problem with the voltage for torque sensor 5 V power source Vcc 2(see page 17-31)
DfC:22A problem with the average for vehicle speed and engine speed(see page 17-33)
Excessive change of the vehicle speed sensor signal{see page 17-33)
DTC: 23A problem with the engine speed signal circuit(see page 17-33)
DTC: 37A problem with the circuit for input motor voltage in the EPS control unit(see page 17-35)
DTC: 41A problem with the motor voltage(see page 17 36)
DfC: 42A problem with the motor driven current (open circuit or short to grounol(see page '17-38)
DTC: 43A problem with the motor driven current (short to power)(see page 17-41)
DTC: 45A problem with the motor driven current (open circuit or short to grou nol(see page 17-38)
DfC: 47A problem with the motor relav in the EPS control unit{see page 17-42)
DTC: 50A problem with the CPU in the EPS control unit(see page 17-43)
DTC: 51A problem with EEPROM in the EPS control unlt(see page 17-43)
DTC: 62Fail-safe relay stuck ON(see page 17-44)
DTC: 64A problem with low battery voltage
Fail-safe relay contact failure
(see page 17-44)
(see page 17-44)
DTC: 66A problem with the motor driven voltage{see page 17 45)
DTC: 67A problem with the torque sensor l/F circuit(see page 17'45)
DTC: 68A problem with the interlock circuit (torque){see page 17-45)
DTC: 69A problem with the interlock circuit (current)(see page 17-46)
17-22

EPS Components
11.
12.
DTC Troubleshooting (cont'dl
Substitute a known-good EPS control unit, and
connect all the disconnected connectors.
Sta rt the engine, and turn the steering wheel from
lock to lock several times.
Does the EPS indicator come on?
YES Go to step 13.
NO -Check for loose or poor connections at the
EPS control unit and the motor connections. lf the
connections are good, replace the EPS control unit
and recheck.l
Stop the engine, and verity the DTC.
ls DTC 43 indicated?
YES-Replace the steering gearbox motor and
recheck. tl
NO-Perform the appropriate troubleshooting for
the code indicated.l
13.
17-42
DTC 47: EPS Control Unit lnternal Circuit(Power Relay)
1. Clear the DTC.
2. Start the engine.
Does the EPS indicator come on?
YES-Go to step 3,
NO-Check for loose wires or poor connections, lf
the connections are good, the system is OK at this
time.I
3. Stop the engine, and verify the DTC.
ls DTC 47 indicated?
YES Check for loose EPS control unit connectors.
lf necessary, substitute a known-good EPS control
unit and recheck.l
NO Perform the appropriate troubleshooting for
the code indicated.I
(

EPS Components
DTC Troubleshootang (cont'dl
DTC 62: EPS Control Unit Internal Circuit
(Fail-safe Relay Stuck ON)
'1. Clear the DTC.
2. Start the engine.
Does the EPS indicator come on?
YES-Go to step 3.
NO-Check for loose wires or poor connections. lf
the connections are good, the system is OK at this
time.I
3. Stop the engine, and verify the DTC.
ls DTC 62 indicated?
YES-Check for loose or poor connections at the
EPS control unit. lf the connections are good,
substitute a known-good EPS control unit. lf the
symptom/indication goes away, replace the
original EPS control unit and recheck.l
NO-Perform the appropriate troubleshooting for
the code indicated. t
17-44
DTC 64: Battery Voltage is Excessively Low
(Fail-safe Relay Contact Failure and Motor
Voltage FallOff)
1. Clear the DTC.
2. Start the engine.
Does the EPS indicatot come on?
YES Go to step 3.
NO Check for loose wires or poor connections. lf
the connections are good, the system is OK at this
trme.l
3. Stop the engine, and verify the DTC.
ls DTC 64 indicated?
YES Go to step 4.
NO Perform the appropriate troubleshooting for
the code indicated.
4. Check the No. '18 (604) fuse in the under-hood fuse/
relay box, and reinstallthe fuse if it is OK.
Is the f use OK?
YES Go to step 5.
NO Replace the fuse and recheck.l
5. Disconnect EPS control unit connector A (2P).
6. Measure the voltage between EPS control unit
connector A (2P) terminal No. 1 and body ground.
-Blwt{r/Bl.ur Hl
\9
I
ls there battety voltage?
YES - Check for loose or poor connections at the
EPS control unit connectors, and check for a poor
ground at G 15 1. lf necessary, substitute a known-
good EPS control unit and recheck.l
NO Repair open in the WHT/BLU wire between
the No. 18 (60,4)fuse and EPS control unit.l
(

EPS Indicator Circuit Troubleshooting
1.Turn the ignition switch ON (ll), start the engine,
and watch the EPS indicator.
Does the EPS indicator come on?
YES lf the EPS indicator comes on and goes off, it's
OK. lf the EPS indicator stays on or blinks. go to
step 12.
NO Go to step 2.
Turn the ignition switch OFF, then ON (ll) again,
and watch the brake system indicator,
Does the brake system indicator come on?
YES-Go to step 3.
NO Repair open in the indicator power source
circuit.l. Blown No. 10 (7.5A)fuse.
. Open in the wire between the No. 10 (7.5A) fuse
and gauge assembly.. Open circuit inside the under-dash fuse/relay box,. Faulty gauge assembly.
Turn the ignition switch OFF,
Connect a jumper wire between the gauge
assembly 22P connector terminal No. 13 and body
ground, then turn the ignition switch ON (ll).
GAUGE ASSEMBLY 22P CONNECTOR (Blue connector)
Wire side of female terminals
Does the EPS indicator come on?
YES-Go to step 5.
NO Inspect the EPS indicator bulb, if the bulb is
OK, replace the bulb circuit board in the gauge
assembly.l
3.
4.
5. Turn the ignition switch OFF.
6. Disconnect EPS control u n it connector C (20P).
7. Turn the ignition switch ON (ll).
8. Connect EPS control unit connector C (20P)
terminal No. 6 to body ground with a jumper wire.
Wire s d€ oflemale16rmina s
Does the EPS indicatot come on?
YES Go to step 9.
NO Repair open in the wire between the gauge
assembly and the EPS control unit.l
Turn the ignition switch OFF.
Disconnect EPS control unit connector A (2P),
Check for continuity between EPS control unit
connector A terminal No. 2 and body ground.
EPS CONTROL UNITCONNECTOA A I2PI
wire s de oftemale terminals
ls there continuity?
YES Check for loose or poor connections at the
EPS control unit. lf the connections are good,
substitute a known-good EPS control unit. lf the
symptom/indication goes away, replace the
original EPS control unit and recheck.I
NO Repair open in the wire or a bad ground at
G151,t(cont'd)
9.
10.
'l 1.
EPS CONTBOL UNIT CONNECTOB C {2OP)
17-47

EPS Components
I
12.
EPS Indicator Circuit Troubleshooting (cont'dl
Turn the ignition switch OFF.
Disconnect EPS control unit connector C (20P).
Turn the ignition switch ON (ll).
Does the EPS indicator come on?
YES-Repair short to ground in the YEUBLU wire
between the gauge assembly and the EPS control
unit, or replace the bulb circuit board in the gauge
assembly.l
NO-Go to step 15.
Measure the voltage between EPS control unit
connector C (20P)terminal No. 10 and body ground.
EPS CONTROL UNIT CONNECTOR C I2OP)
Wire side of female terminals
ls there battery voltage?
YES-Go to step 16.
NO-Repair open in the wire between EPS control
unit connector C (20P) and the No, 10 (7.5A) fuse. t
13.
14.
17-48
16. Measure the voltage between EPS control unit
connector A (2P)terminal No. '1 and body ground.
EPS CONTROL UNITCONNECTON A (2P}
+B (WHT/BLUI H
Itr
v-L
17.
18,
19.
20.
Wire side of female terminals
ls there battery voltage?
YES-Go to step 17.
NO-Check for a blown No. 18 (604) fuse in the
under-hood fuse/relay box or open/short in the
WHT/BLU wire between the under-hood fuse/relay
box and the EPS control unit.l
Turn the ignition switch OFF.
Reconnect EPS control unit connector A (2P).
Turn the ignition switch ON (ll).
Measure the voltage between EPS control unit
connector C (20P)terminal No. 8 and body ground.
EPS CONTROL UNIT CONNECTOR C (2OP)
Wire side of female terminals
ls therc about 10 V?
YES Check for loose or poor connections at the
EPS control unit. lf the connections are good,
substitute a known-good EPS control unit. lf the
symptom/indication goes away, replace the
original EPS control unit and recheck.l
NO Repair short to ground in the BRN wire
between the data link connector and the EPS
control unit.I

EPS Components
Steering Gearbox Removal {cont'd)
22. Move the steering gearbox and tie-rod ends as anassembly to the wheelwell opening on thepassenger's side.
23. Carefully raise the driver's side (pinion side) ofthesteering gearbox (A) and tie-rod (B) until clears themaster cylinder and under-hood fuse relay box,
then remove the steering gearbox. Be careful not to
damage the hoses, lines and wtre narnesses.
17-51

ABS Gomponents
(Component Location Index
UNDER.HOOD FUSE/RELAY BOX
RIGHT-REAR WHEEL SENSORInspection, page 19-59Replacement, page 19-59UNDER.OASH FUSE/RELAY BOX
\L
LEFT.REARWHEEL SENSORInspection, page 19-59Replacement, page 19-59
DATA LINK CONNECTOR I16PIRIGHT.FRONT WHEEL SENSORInspection, page 19-59Replacement, page 19-59
ABS MODULATOR.CONTROL UNITRemoval and Installation, page 19'57LEFT-FRONT WHEEL SENSORInspection, page 19-59Replacement, page 19 59
19-30