2002 HONDA CIVIC brake

Fuel and Emissions Systems
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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.

""rr"a* JIr''lHr/cnN 1
CONNECTOR E
CONNECTOi K
CONNECTOFJ/GRN
IGNITIONSWITCH
lG2
'I
TESTTACHOMETERCONNECTO8
UNDER.HOOD
UNDER.DASHFUSE/RELAY BOX:
UNDER.DASHFUSE/FELAY BOX
Brake pedal pressed: closedBrake pedal releasedr open
POStTtON SWTTCH
,or"-9J3{51re* _{F "_.rl
4 ACG (1oAt1 tGN CO|L t15A)2 A/F HEATER {2OA)17 FUEL PUMP I15A}1O METER {7.5AI14 A/C CLUTCH RELAY {1OA}
11-45

PGM-Fl System
6.
1.
DTC Troubleshooting (cont'dl
DTC P0500: VSS Circuit Malfunction
1. Test-drive the vehicle.
2. Check the vehicle speed with the scan tool.
ls the correct speed indicated?
YES-lntermiftent failure, system is OK at this time.
Check for poor connections or loose terminals at
the VSS and at the ECM.I
NO Go to step 3.
3. Turn the ignition switch OFF.
4. Block the rear wheels, and set the parking brake.
5. Raise the front ofthe vehicle, and make sure it is
securely supported,
Turn the ignition switch ON (ll).
Block the right front wheel, and slowly rotate the
left front wheel.
8. Measure voltage between ECM connector
terminals A18 and A24.
ECM CONNECTOR A {31P)
Wire side of female terminals
Does the voltage pulse between 0 V and 5 V or
between 0V and battery voltage?
YES-Update the ECM if it does not have the latest
software, or substitute a known-good ECM. then
recheck (see page 1 1-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECN4.l
NO Go to step 9.
11-80
9. Turn the ignition switch OFF.
10. Disconnect ECM connector A (3'1P).
1 1. Turn the ignition switch ON {ll}.
12. Blockthe right front wheel. and slowly rotate the
left front wheel.
'!3. lMeasure voltage between ECM connector
terminals A18 and A24.
ECM CONNECTOR A I31PI
Wire side of female terminals
Does the voltage pulse between 0 V and 5 V ol
between 0V and battety voltage?
YES Update the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 1 1-6). lf the symptom/indication
goes away with a known-good ECM, replace the
origlnal ECM.I
NO Check these items:
. A short or an open in the wire between the ECM
(A18) and the VSS.I. lf thewire is OK,testtheVSS (see page 22 71).1

Brake Pedal Position Switch Signal Circuit Troubleshooting
1. Check the brake lights.
Are the brake lights on without pressing the brakepedal?
YES Inspectthe brake pedal position switch(see page 19-6).I
NO Go to step 2.
2. Press the brake pedal.
Do the brake lights come on?
YES-Go to step 3.
NO Go to step 4.
3. Measure voltage between ECM connector
terminals A24 and E22 with the brake pedal
presseo.
ls there battery voltage?
YES-The brake pedal position switch signal is
oK,I
NO Repair open in the wire between the Eclvl(E22) and the brake pedal position switch.l
Wire side of lemale terminals
4. Inspect the No. 7 HORN, STOP (15A) fuse ln the
under-hood fuse/relay box.
ls the tuse OK?
YES- Repair open in the wire between the brake
pedal position switch and the No.7 HORN, STOP( l5A) fuse, Inspect the brake pedal position switch(see page 19-10).1
NO Repair short in the wire between the ECM(E22) and the No.7 HORN, STOP (15A)fuse.
Replace the No.7 HORN, STOP (15A)fuse.t
11-137

ldle Control System
ldle Speed lnspection
NOTE:' Leave the idle air control (lAC) valve connecled.. Before checking the idle speed, check these items:- The malfunction indicator lamp (MlL) has not been
reported on.- lgnition timing- Spark plugs- Air cleaner- PCV system. Pullthe parking brake lever up. Start the engine, and
make sure the headlights are off.
1. Disconnect the evaporative emission (EVAP)
canister purge valve 2P connector.
2. Connect a tachometer (A)to the test tachometer
connector (B), or connect the Honda PGM Tester (C)
or an OBD ll scan tool to the data link connector(DLC) (D) located under the driver's side of the
dashboard.
11-138
4.
3.
5.
6.
Start the engine. Hold the engine at 3,000 rpm with
no load (in neutral) until the radiator fan comes on,
then let it idle.
Check the idle speed with no-load conditions;
headlights, blower fan, radiator fan, and air
conditioner off.
ldle speed should be: 750 t 50 rpm
Let the engine idle for 1 minute with the heater fan
switch on Hl and air conditioner on, then check the
idle speed.
ldle speed should be: 750 t 50 rpm
NOTE: lf the idle speed is not wilhin specification,
go to the Symptom Troubleshooting Index,
Reconnect the EVAP canister purge valve 2P
connector.

PCV System
DTC Troubleshooting
DTC P1505: PCV Air Leakage
1. Reset the ECM (see page 11-4).
2. Start the engine. Hold the engine at 3,000 rpm with
no load (in neutral) until the radiator fan comes on
3. Let the engine idle tor al least 40 seconds with the
throttle fully closed.
4. Check for a DTC P1505 with the scan tool
ls DTC P1505 indicated?
YES-Check these parts for vacuum leaks l
. PCV valve. PCV hose. EVAP canister purge valve
. Throttle body. Brake booster hose
NO - Intermittent failure, system is OK at this
time.l
11-168

Clutch Master Cylinder Replacement
NOTE: Do not spill brake fluid on the vehicle; it may
damage the paint; if brake fluid does contact the paint,
wash it off immediatelV with water.
1. Pry out the lock pin (A), and pullthe pedal pin (B)
out of the yoke. Remove the master cylinder
mounting nuts (C).
Remove the air cleaner housing cover and the air
cleaner housing (see step 6 on page 5-2).
Remove the brake fluid from the clutch master
cylinder reservoir with a syringe.
Remove the clutch line bracket from the frame rail,
and remove the clutch line clip.
Remove the clutch master cylinder (A), and pull it
toward the middle of the engine compartment.
Remove the retaining clip (B). Disconnect the clutch
line (C). Plug the end of the clutch line with a shop
towelto prevent brake fluid from coming out.
g-E
3.
6. Disconnect the reservoir hose (D) fromtheclutch
master cylinder reservoir. Plug the end of the
reservoir hose with a shop towel to prevent brake
fluid from coming out.
7. Remove the O-ring (E) and the clutch master
cylinder seal (F) from the master cylinder.
8. Installthe clutch master cylinder in the reverse
order of removal. Install a new O-ring.
9. Make sure the hose clamps (A) are positioned on
the master cylinder (B) and reservoir (C) as shown.
(cont'd)
UP
i
12-5

Slave Cylinder Replacement
NOTE:. Use fender covers to avoid damaging painted
surfaces.. Do not spill brake fluid on the vehicle; it may damage
the paint; if brake fluid does contact the paint, wash it
off immediately with water.
1. Write down the frequencies for the radio's preset
buttons. Disconnect the negative ( ) cable first,
then the positive (+)cable from the battery.
Remove the battery.
2. Remove the battery tray.
a
Remove the air cleaner housing cover and the air
cleaner housing (see step 6 on page 5-2).
Remove the intake air duct (see step 8 on page 5-3) .
Remove the clutch line bracket (A).
4.
5.
6. Remove the mounting bolts (A) andtheslave
cylinder (B).
Remove the roll pins (C). Disconnect the clutch line(D), and remove the O-ring (E). Plug the end of the
clutch line with a shop towel to prevent brake fluid
f rom coming out.
Installthe slave cylinder in the reverse order of
removal. Install a new O-ring (A).
7.
,,6NJ'
=--#.q!4sEn(P/N 08798-90021
9.
(Brak6 Assembly Lube)
Pullthe boot (B) back, and apply brake assembly
lube to the boot and slave cylinder rod (C). Reinstall
the boot.
Apply super high temp urea grease (P/N 08798-
9002) to the push rod of the slave cylinder. Tighten
the slave cylinder mounting bolts to 22 N m (2.2
kgf m, 16lbf.ft).
(cont'd)
12-7
10.