2002 HONDA CIVIC power

Fuel and Emissions Systems
Symptom Troubleshooting Index
When the vehicle has one of these symptoms, check the diagnostic trouble code (DTC) with the scan tool. lf there is no
DTC, do the diagnostic procedure for the symptom, in the sequence listed, until you find the cause.
SvmotomDiaqnostic procedureAlso check lor
Engine will not sta rt
(MlL works OK, no DTCS set)
1. Test the battery {see page 22-50).
2. Test the starter (see page 4-8).
3. Troubleshoot the fuel pump circult (see page 11
141).
Low compressron
No ignition spark
lntake air leaks
Locked up engine
Broken timing chain
Contaminated fuel
Engine will not start (MlL
comes on and stays on, or
never comes on at all, no
DTCS set)
Troubleshoot the l\4lL circuit (see page 1 '1-97).
Engine will not start
(immobilizer indicator stays
on or flashs)
Troubleshoot the immobilizer system (see page 22-165).
Hard starting(MlL works OK, no DTCS set)
1. Testthe battery (see page 22-50).
2. Checkthe fuel pressure (see page 11-145).
Low compression
Intake air leaks
Contaminated fuel
Cold fast idle too low(MlL works OK. no DTCS set)
1. Do the ECM idle learn procedure (see page 11-139).
2. Checkthe idle sDeed (see paqe 11-138).
Cold fast idle too high
(MlL works OK, no DTCS set)
Do the ECI\4 idle learn procedure (see page 1 1- 139).
Checkthe idle speed {see page 11-138).
Inspect/adjust the throttle cable (see page 1 '1-'163).
Inspect and test the throttle body {see page 1 1-160}.
']
2.
3.
ldle speed fluctuates
(MlL works OK, no DTCS set)
1. Dothe ECM idle learn procedure (see page 11-'139).
2. Check the idle speed (see page 11-138).
3, Inspecvadjust th e throttle cable (see page 11''163).
4. Insoect and test the throttle bodv (see paqe 11- 160)
Intake air leaks
After warming up, idle speed
is below specifications with
no load
{MlL works OK, no DTCS set)
1. Do the ECIVI idle learn procedure (see page 1 1- 139).
2. Troubleshootthe alternator FR signal circuit (see
page 11-'134).
3. InsDect and test the throttle bodv {see paqe 1 1-160).
Vacuum hose clogged/
cracked/poor
connectron
After warming up, idle speed
is above specifications with
no toao(MlL works OK. no DTCS set)
1. Do the ECM idle learn procedure {see page 1'j-139).
2. Troubleshoot the alternator FR signal circuit(see
page 11-134).
Low power
(MlL works OK, no DTCS set)
1. Check the fuel pressure(seepagell-145).
2. Inspect and test the th roftle body (see page 11-160).
3. Inspecvadjust the throttle cable (see page 11-'163).
Low compressron
Camshaft timing
problem
Engine oil levelprootem
Engine stalls(MlL works OK. no DTCS set)
1. Do the ECM idle learn procedure (see page 1'l'139).
2. Check the fuel pressure{seepagell-145).
3. Check the idle speed (see page I 1-138).
4. Troubleshootthe brake pedal position switch signal
circuit (see paqe 11-137).
lntake air leaks
Faulty harness and
sensor connections
\
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11-10
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ECM Inputs and Outputs at Connector A (31P)
NOTE: Standard battery voltage is 12 V.
1AFS]TC2
]GP23IGPl^:^ I -:,6AFS+1
CKPIKS
'10
SG2t112ACV15TPST6AFS_18
VSS
19IVAP2Avcc221vccl
22
HTC+
23LG225CMPA
26CMPB(rDc)
27tGPts,l28rcPts329tGPts230GPLS 1
Wire side ol female terminals
Terminalnumb€rWho colorforminal nameDescriptionSignal
ELKAVHTAFSHTC (AIR FUEL RATIO(4./F)SENSOR HEATERCONTROL}
Drives Ay'F sensor heaterWith ignit'on switch ON {ll): battery voltageWith fully warmed up engine runnang: 0 V
2YEUBLKIGP2 (POWEB SOURCE)Power source for the ECMcircuitWith the ignition switch ON 1ll): battery voltageWith the ionition switch OFF: about 0 V3YEUBLKIGPl {POWER SOURCE)Power source for the ECMWith the ignition swatch ON {ll): battery voltageWith the ionition switch OFF: about 0 V4BLKPG2 (POWER GROUNDGround forthe ECM circuitLess than 1.0 V at all times5BLKPG1 (POWER GROUNDGround forthe ECM circuitLess than 1.0 V at all times6REDAFS + (AIR FUEL RATIO(A,/F}SENSOR, SENSOR 1+ stDE)
Detects Ay'F sensor{sensor 1) signal
18LUCKP (CRANKSHAFTPOSITION SENSOR)Detects CKP sensor signalWith engine running: pulses
9BED/BLU)K SENSOB)Detects knock sensor siqnalWith enqine knocking: pulses10YEL2 {SENSOR;ROUND);ROUND)Sensor qrounrLessthan 1.0V at elltimesG1 {SENSORSensor qroun(Lessthan 1.0V at alltimes12BLIVREDIACV (IDLE AIR CONTROL(IAC)VALVE)Drives IAC valveWith engine runningr duty controlled
RED/BLKTPS (THROTTLE POSITIONSENSOR)Detects TP sensor signalWith throttle fully open: about 4.8 VWith thronle fullv closed: ahout 0-5 VREDI/ELAFS (AIR FUEL RATIO(4,/F)SENSOR, SENSOB 1SIDE)
Detects !y'F sensor(sensor 1)signal
18WHT/GRNVSS (VEHICLE SPEEDSENSOR)Detects VSS signalWath ignition switch ON (lli and front wheelsrotating: cycles from about 0 V to about 5 V or
(cont'd)
11-19

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
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Fuel and Emissions Systems
(System Descriptions (cont'dl
VTC system. The VTC system makes continuous intake valve timing changes based on operating conditions.. Intake valve timing is optimized to allow the engine to produce maximum power.'CamangleisadvancedtoobtaintheEGReffectandreducethepumpingloss.Theintakevalveisclosedquicklyto
reduce the entry of the airlfuel mixture into the intake port and improve the charging effect.. Cam angle is reduced at idle to stabilize combustion and reduces engine speed.'lfamalfunctionoccurs,theVTCsystemcontrol is disabled and the valve timing is fixed at the fully retarded position.
MAXIMUM VTC ADVANCE 50'
i l(-4 sHoRT oVERLAP
'+-|l LoNG oVERLAP
VTEC system' The VTEC system changes the cam profile to correspond to engine speed. lt maximizes torque at low engine speedand output at high engine speed.. The low lift cam is used at low engine speeds, and the high lift cam is used at high engine speeds.
LOW SPEED VALVE TIMINGHIGH SPEED VALVE TIMING
TDC
MAXIMUM VTC ADVANCE 50'
11-30

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.

DTC P0563: ECM Power Source Circuit
U nexpected Voltage
1. Reset the ECI\4 {see page l1-4}.
2. Turn the ignition switch OFF.
3. Wait 5 seconds.
4. Turn the ignition switch ON {lll.
ls DTC P0563 indicated?
YES Go to step 5.
NO-lntermiltent failure, system is OK at this time.
Check for poor connections or loose terminals at
the No. 6 ECU (ECM) {15 A) fuse in the under-hood
fuse/relay box and at the ECM.I
Turn the ignition switch OFF.
Disconnect ECI\4 connector E {31P).
Turn the ignition switch ON (ll).
lvleasure voltage between ECM connector terminal
E7 and body ground.
6.
7.
8.
ECM CONNECTOR E {31P}
Wire side ol remale terminals
ls there battery voltage?
YES Go to step 12.
NO Go to step 9.
MRLY
9.
10.
Remove the glove box (see page 20-63).
Remove the PGM-FI main relay 1 (A7.
Check for continuity between ECM connector
terminal E7 and body ground.
ECM CONNECTOR E 131P)
MRLY{RED/YEL)
Wire side of {emale terminals
ls there continuity?
YES-Repair short in the wire between the ECM
{E7) and the PGM-Fl main relay 1 ,I
NO Replace the PGM-Fl main relay 1.1
Turn the ignition suitch OFF.
Reconnect ECM connector E (31P).
11.
tt.
'13.
(conl'd)
11-81

PGM-FISystem
DTC Troubleshooting (cont'dl
14. Measure voltage between ECM connector terminal
E7 and body ground.
ECM CONNECTOR E 13lPI
MRLYIBEO/YEL)
Wire side of female terminals
ls there battery voltage?
YES Go to step 15.
NO-Update the ECM if it does not have the latest
software, or substitute a known-good EClvl, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.I
Disconnect ECI\4 connector A (31P).
Turn the ignition switch ON (ll).
Measure voltage between body ground and ECIM
connector terminals 43 and 42 individually.
ECM CONNECTOR A {3.IP)
IGP2 IGP1(YEI./BLX) (YEL/BLKI
Wire side of female lerminals
ls there battery voltage?
YES-Go to step 18.
NO Update the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM/PCl\4.1
15.
to.
17.
11-82
18.
19.
Remove the glove box (see page 20-63).
Remove the PGM-FI main relay '1 {A).
Measure voltage between body ground and ECM
connector terminals A3 and A2 individually.
ECM CONNECTOR A {31PI
IGP2 IGP1(YEL/BLK) (YEL/BLK)
Wire side of female terminals
I s there battery v oltage?
YES Repair shortto power in the wire between
the ECI\4 (A2.A3) and the PGM-Fl main relay 1.1
NO Replacethe PGM Fl main relay 1.!
20.

PGM-FI System
DLC Circuit Troubleshooting {cont'dl
7. Disconnect EClvl connector E (31P). Make sure the
OBD llscan tool or Honda PGM Tester is
disconnected from the DLC.
8. Check for continuity between DLC terminal No. 7
and body ground.
DATA LINK CONNECTOR IDLC)
Ierminal side of female terminals
ls there continuity?
YES-Repair short to ground in the wire between
DLC terminal No. 7 and the ECM {E23). After
repairing the wire, check the DTC with the OBD ll
scan tool/Honda PGM Tester, and go to the DTC
Troubleshooting index. I
NO Go to step 9.
Check for continuity between DLC terminal No. 7
and ECM terminal E23,
ECM CONNECTOR E {31PI
Terminal side of female terminals
9.
K-LINE {LT BLU)
DATA LINK CONNECTOR
11-110
10.
1 'I.
tJ.
ls there continuity?
YES U pdate the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECI\4.I
NO Repair open in the wire between DLC terminal
No.7 and the ECM {E23). After repairing the wire,
check the DTC with the OBD ll scan tool/Honda
PG l\4 Tester, and go to the DTC Troubleshooting
Index.l
Turn the ignition switch OFF.
Disconnect ECI\4 connector E (31P). l\4ake sure the
OBD ll scan tool or Honda PGM Tester is
disconnected from the DLC.
Turn the ignition switch ON (ll).
Measure voltage between DLC terminals No. 5 and
No.7.
DATA LINK CONNECTOR {DLC}
Terminal side of female terminals
Is there 0 V?
YES Update the ECM if it does not have the latest
software, or substitute a known-good ECI\4, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.I
NO Repair short to power in the wire between the
DLC terminal No.7 and the ECM (E23). After
repairing the wire, check the DTC with the OBD ll
scan tool/Honda PGM Tester, and go to the DTC
Troubleshooting index. I
t