2003 HONDA CIVIC ima

Fuel and Emissions Systems
System Descriptions (cont'd)
ECM Data (cont'd)
w
DataDescriptionOpera'ting ValueFreeze Data
Fuel System
Status
Fuel system status is indicated as "open" or "closed".
Closed: Based on the A,/F Sensor output, the ECM
determines the airlfuel ratio and controls the amount of
injected fuel.
Open: lgnoring Ay'F Sensor output, the ECM refers to
signals from the throttle position {TP), manifold absolute
pressure (MAP), intake air temperature (lAT), barometric
pressure (BARO), and engine coolant temperature (ECT))
sensors to control the amount of iniected fuel.
At idle speed: closedYES
Short Term
FuelTrim
The airlfuel ratio correction coefficient for correcting the
amount of injected fuel when the fuel system status
is "closed." When the ratio is leaner than the
sloichiometric ratio, the ECM increases short term fuel
trim gradually, and the amount of iniected fuel increases.
The airlfuel ratio gradually gets richer, causing a lower
oxygen content in the exhaust gas. Consequently, the
short term fuel trim is lowered, and the ECM reduces the
amount of injected fuel.
This cvcle keeps the airlfuel ratio close to the
stoichiometric ratio when in closed loop status.
o.7 1.5YES
Long Term
Fuel Trim
Long term fuel trim is computed from short term fuel trim
and indicates changes occurring in the fuel supply system
over a long period.
lf long term fuel trlm is higher than 1.00, the amounl of
injected fuel must be increased. lf it is lower than 1.00, the
amount of injected fuel must be reduced.
0.8 1.2YES
Intake Air
Temperature
{IAT)
The IAT sensor converts intake air temperature into
voltage and signals the ECM. When intake air
temperature is low, the internal resistance ofthe sensor
increases, and the voltage signal is higher.
With cold engine:
Same as ambient
temperature and ECT
YES
Throttle
Position
Based on the accelerator pedal position, the opening
anole of the throttle valve is indicated.
At idle speed:
about 10 %
YES
lgnition
Timing
lgnition timing is the ignition advance angle set by the
ECM. The ECM matches ignition timing to driving
conditions.
At idle speed: 8" t 5"
|' tuL wnen rne >L)
service signal line is
jumped with the Honda
PGM Tester
NO
Calculated
Load Value
(cLV)
cLV is the enoine load calculated from IMAP data.At idle speed:
12 34%
At 2.500 rpm with no
toao:'t4- 34%
YES
11-14
\.,
ra

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
{

DTC Pl259: WEC System Malf unction
SpecialTools Required. Pressure gauge adapter 07NAJ P07010A
. A/T low pressure gauge w/panel 07406-0070300. A/T pressure hose 07406-0020201. Av/T pressure hose,2,210 mm 07IMAJ-PY4o11A
. l"/T pressure adapter 07MAJ-PY40120
. Oil pressure hose 07ZAJ-S54,4200
1. Reset the ECM (see page 11-4).
2. Check the engine oil level, and refill ifnecessary.
3. Start the engine. Hold the engine at 3,000 rpm with
no load {in neutral) until the radiator fan comes on.
4. Road testthe vehicle:
Accelerate in the 1st gear to an engine speed over
4.000 rpm. Hold the speed for at least 2 seconds. lf
DTC P1259 is not repeated during the first road test,
repeat the test two more times.
ls DTC P1259 indicated?
YES Go to step 5.
NO-lntermittent failure, system is OK at this time
Check the oil consumption if oil was added in step
2. Check for poor connections or loose terminals at
the VTEC solenoid valve, the VTEC oil pressure
switch, and at the ECI\4. I
5, Turn the ignitjon switch OFF.
6. Disconnect the VTEC oil pressureswitch 2P
connector.
7. Check for continuity between VTEC oil pressure
switch 2P connector terminals No. 1 and No. 2
VTEC OIL PRESSURE SWITCH2P CONNECTOR
Terminal side of male terminals
Is there continuity?
YES-Go to step 8.
NO Replace the VTEC oil pressure switch.l
8. Turn the ignition switch ON (ll).
9. Measure voltage between VTEC oil pressure switch
2P connector terminal No. 1 and body ground
ls there battety voltage?
YES Go to steP 14.
NO-Go to step 10.
(cont'd)
VTEC OIL PRESSURE SWITCH2P CONNECTOR
VTPSW
/T {BLU/BLK}
{.--r r-l'--.l
J II
oI
Wire side of female terminals
11-123

Clutch
Clutch Pedal, Clutch
Adjustment
NOTE:. To check the clutch pedal position switch(see page 4-45).. To check the clutch interlock switch (see page 4-6).. Remove the driver's side floor mat before adjusting
the clutch pedal.. The clutch is self-adjusting to compensate for wear.. lf there is no clearance betweenthe mastercylinderpiston and push rod, the release bearing will be held
against the diaphragm spring. which can result in
clutch slippage or other clutch problems.
1. Loosen the clutch pedal position switch locknut (A),
and back off the clutch pedal position switch (B)
until it no longer touches the clutch pedal (C).
J9.8 N.m(1.0 kgf.m,7.2 lbf.ft)
A9.8 N.m11.0 kgf.m, 7.2 lbf.ft)
o18 N.m{1.8 kgf.m,13 tbf.ftl
Loosen the clutch push-rod locknut (D). and turn
the push rod (E) in or out to get the specified height(F), stroke (G). free play (H) and disengagement
height (l) atthe clutch pedal.
Clutch PedalStroke: 130 140 mm(5.12 5.51 in.l
Clutch Pedal Free Play: l0 16 mm (0.39-0.63 in.)
Clutch Pedal Height: 193 mm (7.60 in.)
Disengagement
Height: 115 mm (4.53 in.)
Between Floor And
Carpet Height(Approximate Valuel: 38 mm {1.50 in.l
12-4
Pedal Position Switch, and Clutch Interlock Switch
3. Tighten the clutch push-rod locknut (D).
4. With the clutch pedal released. turn the clutchpedal position switch (B) in until it contacts the
clutch pedal (C).
5. Turn the clutch pedal position switch {B) in an
additional 3/4 to 1 turn.
6. Tighten the clutch pedal position switch locknut (A).
7. Loosen locknut (J)and the clutch interlock switch(K).
8. Press the clutch pedal to the floor.
9. Release the clutch pedal 10 'l6mm(0,39 0.63in.)
from the fully pressed position, and hold it there.
Adjust the position of the clutch interlock switch (K)
so that the engine will start with the clutch pedal in
thls position.
10. Tighten the clutch interlock switch locknut (J).

EPS Components
aGeneral Troubleshooting Information
EPS Indicator
Under normal conditions, the EPS indicator comes on when
the ignitlon switch is turned to the ON (ll) position, then goes
off after the engine is started. This indicates that the bulb and
its circuit are operating correctly.
lf there is any trouble in the system after the engine is started,
the EPS indicator will stay on, and the power assist is turned
off.
When EPS indicator light comes on, the control unit
memorizes the DTC. In this case, the control unit will not
activate the EPS system after the engine starts again, but it
keeps the EPS indicator on.
When DTC 12, 16, 17, 18 or 67 is stored in the control unit, the
EPS indicator will stay on until the DTC is erased. When a
problem is detected and the EPS indicator comes on, there are
cases when the indicator stays on untilthe ignition switch is
turned 0FF, and cases when the indicator goes off
automatically when the system returns to normal. Even though
the system is operating normally, the EPS indicator will come
on under the following conditions:
Condition '1:
. The vehicle was traveling at least 12.4 mph (20 km/h), then. A rapid change in vehicle speed was detected, then. The vehicle (or the vehicle speed sensor signal) stopped for
at least 5 seconds. The engine speed was still 'l,640rpmorhigherforatleastS
seconds
Condition 2:
After the vehicle (or the vehicle speed sensor signal) has
stopped for at least 10 seconds, yet the engine speed was still
1,640 rpm or higherfor at least 20 seconds.
Condition 3:
When the engine speed is 280 rpm or less, and the vehicle is traveling at
a speed of 6,2 mph (10 km/h) or more for 3 seconds.
To determine the actual cause ofthe problem, question the
customer about the conditions during which the problem
occured, taking the above conditions into consideration.
Diagnostic Trouble Code (DTCI
. lf the CPU cannot be activated, or itfails,the EPS indicator
comes on, but the DTC is not memorized.. The memory can hold any number of DTCS. However, when
the same DTC is detected more than once, the most recent
DTC is written over the prior DTC, therefore only one
occurrence is memorized.. The DTCS are indicated repeatedly untilthe ignition switch is
turned OFF.. lf the DTC is not memorized,the EPS indicator blinks.
. The DTCS are memorized in the EEPRO| (non-volatile
memory) therefore the memorized DTCS cannot be erased
by disconnecting the battery. Perform the specified
procedures to clear DTCS.
Self-diagnosis
Self-diagnosis can be classified into two categories:.Initial diagnosis: performed right after the engine
starts and until the EPS indicator goes off.. Regular diagnosis: performed right after the initial
diagnosis until the ignition switch is turned OFF.
The EPS control unit performs the following functions
when a problem is detected by self-diagnosis;
'1. Turns on the EPS indicator.
2. Memorizes the DTC.
3. Stops power assist and manual steering operation
begrns.
NOTE:. When DTC 23 (a problem with the circuit for
engine speed signal) is detected, the power
assist will return to normal when the vehicle
speed is 0.62 mph (1 km/h) or above.. Fot DfCs 22,23, 64, or 66 the EPS indicator goes
off automatically when the system relurns to
normal. For all other codes, the EPS indicator
goes off when the system is OK after the ignition
switch is turned from OFF to ON (ll).
Restriction on Power Assist Operation
Repeated extreme steering force. such as turning the
steering wheel continuously back-and-forth with the
vehicle stopped, causes an increase of power
consumption in the EPS motor. The increase of electric
current causes the motor to heat up. Because this heat
adversely affects the system, the control unit monitors
the electric current of the motor.
When the control unit detects heat build-up in the motor,
it reduces the electric current to the motor gradually to
protect the system, and it restricts the power assist
operation. The EPS indicator does not come on during
this function.
When steering torque is not applied to the steering
wheel, or when the ignition is turned off, and the motor
cools, the control unit will restore the power assist
gradually until it's fully restored (after approximately 15
minutes maximum).
17-18

Front Brake Disc lnspection
Runout
1. Raise the front of the vehicle, and support it with
safety stands in the proper location (see page 1-8).
Remove the front wheels.
2. Remove the brake pads (see page 19-11).
3. Inspect the disc surface for damage and cracks.
Clean the disc thoroughly, and remove all rust
4. lnstall suita ble flat washers (A) andwheel nuts,and
tighten the nuts to the specified torque to hold the
brake disc securely against the hub.
Set up the dial gauge against the brake disc as
shown, and measure the runout at 10 mm (0 4 in.)
from the outer edge of the disc.
Brake Disc Runout:
Service Limit: 0.10 mm (0.00tt in.l
lf the disc is beyond the service limit, refinish the
brake disc.
Max. Retinish Limit: 19.0 mm (0.75 in.)
NOTE:. lf the brakedisc is beyondtheservice limitfor
refinishing, replace it (see page 18-1 1).
. A new disc should be refinished if its runout is
greater than 0.10 mm (0.004 in.).
Thickness and Parallelism
1. Raise the front of the vehicle, and support it with
safety stands in the proper location (see page 1-8).
Remove the front wheels.
2. Remove the brake pads (see page 19-11).
3. Using a micrometer, measure disc thickness at
eight points, approximately 45" apart and 10 mm
{0.4 in.) in from the outer edge of the disc.
Brake Oisc Thickness:
Standard: 20.9 21.8 mm {0.82-0.86 in.}
Max. Refinishing Limit: 19.0 mm 10.75 in.)
Brake Disc Parallelism: 0.015 mm 10.0(X)6 in.)
max.
NOTE: This is the maximum allowable difference
between the thickness measurements
10 mm lo.it in.l
lf the smallest measurement is less than the max.
refinishing limit, replace the brake disc (see page
18-11).
lf the disc is beyond the service limit for parallelism,
refinish the brake disc with an on-car brake lathe.
The Kwik-Lathe produced by Kwik-way
Manufacturing Co. and the "Front Brake Disc
Lathe" offered by Snap-on Tools Co. are approved
for this operation.
4.
': . --'t-'"'-
t,.
19-13

Conventional Brake Components
Rear Brake Disc Inspection
Runout
1. Raise the rear of the vehicle, and support it with
safety stands in the proper location (see page 1-8).Remove the rear wheels,
2. Remove the brake pads (see page 19-20).
3. Inspect the disc surface for damage and cracks.
Clean the disc thoroughly, and remove all rust,
4. lnstall suita ble f lat washers (A) and wheel nuts, andtighten the nuts to the specified torque to hold thebrake disc securely against the hub.
108 N.m (11.0 kgf.m,80lbf.ft)
Set up the dial gauge against the brake disc as
shown. and measure the runout at 10 mm (0.4 in.)
from the outer edge of the disc.
Brake Disc Runout;
Service Limit: 0.10 mm {0.004 in.)
lf the disc is beyond the service limit, refinish thebrake disc.
Max. Refinish Limit: 9.0 mm (0.35 in.)
NOTE:. lf the brake disc is beyondtheservice limitfor
refinishing, replace it (see page 18-26).. A new disc should be refinished if its runout isgreater than 0.10 mm (0.004 in.).
19-22
Thickness and Parallelism
1. Raise the rear of the vehicle, and support with
safety stands in the proper location (see page l-g).Remove the rear wheels.
2. Remove the brake pads {see page 19 20).
3, Using a micrometer, measure disc thickness ateight points, approximately 45'apart and 10 mm
{0.4 in.) from the outer edge of the disc.
Brake Disc Thickness:
Standard: 9.9-10.1 mm (0.389 0.397 in.l
Max. Retinishing Limit: 9.0 mm (0.35 in.)
Brake Disc Parallelism: 0.016 mm 10.0006 in.)
max.
4.lf the smallest measurement is less than the max.
refinishing limit, replace the brake disc (see page
18-26).
lf the disc is beyond the service limit for parallelism,
refinish the brake disc with an on-car brake lathe.