2002 HONDA CIVIC air condition

DTC P0300: Random Misfire and Any Combination of the Following:
DTC P0301: No. 1 Cylinder Misfire
DTC P0302: No. 2 Cvlinder Misfire
DTC P0303: No, 3 Cvlinder Misfire
DTC P0304: No. 4 Cvlinder Misfire
NOTE:. lfthe misfiring is frequent enough to trigger detection of increased emissions during two consecutive driving cycles.
the MIL will come on, and DTC P0300 (and some comlrination of P0301 through P0304) will be stored.. lf the misfiring is frequent enough to damage the catalyst, the MIL will blink whenever the misfiring occurs, and OTC
P0300 (and some combination of P0301 through P0304) will be stored. When the misfirlng stops, the MIL will remain
on.
1. Troubleshoot the following DTCs first if any of them were stored along with the random misfire DTC(s):
P0'107, P0108, P1128, P1129r N4anifold absolute pressure (MAP) sensor
P0111. P0'172t Fuel svstem
P0335. P0336: Crankshaft position (CKP) sensor
P0505: ldle control system
P1 149, Pl 162, P1 163, P1 164, P 1 165: Air fuel ratio (Ay'F) sensor
P1259: VTEC system
P1361, P1362: Camshaft position (CMP) sensor B {Top dead center (TDC) sensor)
P1519: ldle air control (lAC) valve
2. Test-drive the vehicle to verify the symptom.
3. Findthesymptom inthechart below, and dothe related procedures in the order listed until you find the cause.
SymptomProcedure(slAlso check foi:
Random misfire only
at low RPM and
under load
Check fuel pressure (see page 1 1-145).. Low compressron.. Low quality fuel.
Random misfire only
du ring acceleration
Check fuel pressure (see page 11-145).Malfunction in the
VTEC system (see page
1't-123).
Random misfire at
high RPM, under
load, or under
random conditions
Check fuel pressure (see page 11-145).Correct engine valve
clearances (see page 6-
91.
11-71

16.Test-drive the vehicle for several minutes in the
range of the freeze data or under various
conditions if there was no freeze data.
Check for a DTC or a Temporary DTC with the scan
Tool.
ls DTC or Temporary DTC P0301, P0302, P0303
or P0304 indicated?
YES Go to step 18.
NO lntermittent misfire due to bad contact at the
injector connector (no misfire at this time). Make
sure the injector connection is secure. Check for
poor connections or loose terminals at the
injector.l
Determine which cylinder(s) had the misfire.
Does the misf ire occur in the cylinder where the
i njector w as exchanged ?
YES- Replace the faulty injector.I
NO-Go to step 19.
Turn the ignition switch OFF.
Disconnect the ignition coil 3P connector from the
problem cylinder.
Turn the ignition switch ON (ll).
't7 .
18.
19.
20.
22. Measure voltage between ignition coil 3P
connector terminal No. 3 and body ground.
IGNITION COIL 3P CONNECTOR
Wire side ol female terminals
ls there battery voltage?
YES-Go to step 23.
NO Repair open in the wire between the No. 1
IGN COIL (15A)fuse and the ignition coil.I
Turn the ignition switch OFF.
Check for continuity between ignition coil 3P
connector terminal No. 2 and body ground.
IGNITION COIL 3P CONNECTOR
Wire side ot female terminals
ls there continuity?
YES Go to step 25.
NO Repair open in the wire between the ignition
coiland G101.1
Disconnect ECM connector A {31P)
23.
24.
(cont'd)
11-73

ldle Control System
DTC Troubleshooting
DTC P0505: ldle Control System Malfunction
NOTE: lf DTC P1519 is stored atthe same time as DTC
P0505, troubleshoot DTC P1519 first, then recheck for
DTC P0505.
1. 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,
2. Checkthe engine speed at idle with no,load
conditions: headlights, blower fan, rear defogger,
radiator fan, and air conditioner off.
Is the engine running at 750t50 rpm?
YES - Intermittent failure, system is OK at this
trme.I
NO lf the idle speed is less than 700 rpm, go to
step 3; if it's 800 rpm or higher, go to step 4.
3. Disconnect the idle air control {lAC) valve3P
connector.
Does the engine speed increase or fluctuate?
YES- Check the idle speed {see page 1 1-138). lf the
idle will not adjust properly, clean the passage in
the throttle body, and then adjust the idle. I
NO- Replace the IAC valve.I
4. Turn the ignition switch OFF.
5. Remove the intake air duct from the throttle body.
6. Start the engine, and let it idle.
11-130
(
7. Put your fingers on the lower pon (A) inthethrottle
oooy.
Does the engine stall?
YES Checkthe idle speed (see page 11-138). lfit's
out of specification, replace the IAC valve.l
NO With the throttle valve completely closed,
check for vacuum leaks, and repair as necessary.l

A/G Signal Circuit Troubleshooting
Turn the ignition switch ON (ll).
Momentarily connect ECM connector terminals 424
and E18 with a jumper wire several times.
1.
2.
5.
Wire side of female terminals
ls there a clicking noise I rom the NC compressor
clutch?
YES Go to step 3.
NO-Go to step 6.
Sta rt the engine.
Turn the blower switch ON.
Turn the Ay'C switch ON.
Does the NC operate?
YES-The air conditioning signal is OK.I
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 €CM.l
6. Momentarily connect under-hood tuse/relay box
14P connector terminal No. 10 to body ground with
a jumper wire several times.
UNDER.HOOD FUSE/RELAY BOXI4P CONNECTOR
12356
1891011IJ14
ACC (RED)
JUMPER WIRE
Wire side of female terminals
ls there a clicking noise f rom the NC compressor
clutch?
YES- Repair open in the wire between the ECM(E'18) and the Ay'C clutch relay.l
NO- Check the A/C system for other symptoms.l
11-133

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.

EVAP System
DTC Troubleshooting (cont'd)
DTC Pl457: EVAP Control System(EVAP Canister System)
Leakage
The fuel system is designed to allow specified
maximum vacuum and pressure conditions. Do not
deviate from the vacuum and pressure tests as
indicated in these procedures. Excessive pressure/
vacuum would damage the EVAP components or
cause eventual fuel tank system failure.
SpecialTools Required
Vacuum pump/gauge, 0-30 in.Hg A973X-041-XXXXX
This is a two-trip code. Once cleared, it cannot be
reproduced in one trip. Also, certain specific driving
and ambient conditions must occur before the ECfM will
complete the system checks, Additional test drives may
still not meet the specific conditions needed to16^r^.1' '^6 rh6 ^^.16
Follow these troubleshooting procedures carefully to
ensure the integrity of the system and to confirm the
cause of the problem or code.
NOTE: Fresh fuel has a higher volatility lhat creates
greater pressure/vacuum. The optimum condition for
testing is fresh fuel, and there must be less than a full
tank. lf possible, to assist in leak detection, add I gallon
of fresh fuel to the tank (as long as it will not fill the
tank), just before starting these procedures.
EVAP Canister Purge Valve Test
1. Disconnect the vacuum hose from the EVAP
canister purge valve (A), and connect a vacuumpump to the hose.
11-180
4973X-041-XXXXX
ECM CONNECTOR A I24P'
Wire side of lemale terminals
4.
7.
2. Turn the EVAP canister purge valve on with the
Honda PGM Tester, or connect ECM connector
terminal 821 to body ground with a jumper wire.
Turn the ignition switch ON (ll).
Apply vacuum to the hose.
Does the valve hold vacuum?
YES-Go to step 5.
NO-The EVAP canister purge valve is OK. Go to
step 10.
Turn the ignition switch OFF.
Disconnect the EVAP canister purge valve 2P
conneclor,
Check for continuity between EVAP canister purge
valve 2P connector terminal No. 2 and body ground.
EVAPCANISTEN PURG€VALVE 2P CONNECTOR
-4-
lll2l-fircs
IYEL/8Lu)(f])
I
Wire side offemale lerminals
ls there continuity?
YES-Go to step 8.
NO Repair open in the wire between the EVAP
canister purge valve and the ECM/PCM (821).I
Turn the ignition switch ON (ll).
t
b.
8.

DTC 22: Vehicle Speed Sensor Signal
DTC 23: Engine Speed Signal
NOTE:. lf the MIL indicator is ON, troubleshoot the PGIVI-Fl
system first.. 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 rapld change in vehicle speed was detected,
then. The vehicle (or the vehicle speed sensor signal)
stopped for at least 5 seconds, and. The engine speed was still 1,640 rpm or higher for
at least 5 seconds- Condition 2:
After the vehicle (or the vehicle speed sensor
signal) has stopped for at least 10 seconds, yetthe
engine speed was still 1,640 rpm or higher for at
least 20 seconds.- Condition 3:
When the vehicle speed is 10 km/h (6.2 mph) or
above and the engine is running at 280 rpm or
below for 3 seconds.
1. Start the engine and check the tachometer.
ls the tachometer working correctly?
YES- Go to step 2.
NO-Go to step 9.
2. Test-drive the vehicle above 15 km/h {9.3 mph).
ls the speedometer working correctly?
YES Go to step 3.
NO-Perform the speedometer system
troubleshooting {see page 22-651.a
3.Block the rear wheels and raise the 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, and measure the voltage between
EPS control unit connector C (20P)terminal No.7
and body ground.
EPS CONTROL UNIT CONNECTOR C {2OP)
Does the voltage pulse 0 V and 5 V?
YES Go to step 6.
NO Repair open in the wire between the EPS
control unit and the VSS. lf the wire is OK,check for
a loose or poor connections at the EPS control unit.
lf necessary, substitute a known-good EPS control
unit, and recheck.l
(conr'd)
4.
5.
Wire side of female terminals
17-33

ABS Components
DTC Troubleshooting (cont'dl
7. Check the resistance between the appropriate
wheel sensor (+) and ( ) circuit terminals {seeta ble).
DTCAppropriate Terminal
l+) Side*lSide
11 {Riqht-front)No.5: FRS (*)No.4:FRS 1-)'13 {Left-front)No. 7: FLS {+iNo.6: FLS (-
15 (Rioht-rear)No. 2: RBS {+)No. 1:RBS (-)
17 (Left-rear)No.9: RLS 1-No.8: BLS (-
ABS CONTROL UNIT 31P CONNECTOR
Wire side of female terminals
Is the rcsistance between 450 2,000 A ?
YES Check for a loose ABS control unit3lP
connector. lf necessary. substitute a known-good
ABS modulator-control unit, and recheck.l
NO Go to step 8.
Disconnect the harness 2P connector from theappropriate wheel sensor, and check the resistance
between the (+) and { )terminalsof thewheel
sensor.
ls the resistance between 450- 2,000 Q ?
YES-Repair open in the (+) or (-) circuit wire, orshort between the (+) circuit wire and the { )circuit wire between the ABS modulator-control
unit and the wheel sensor.l
NO Replace the wheel sensor.l
19-46
DTC12,14, 16, 18: Wheel Sensor Putse
Signal
NOTE: lf the ABS indicator comes on for the reasonsdescribed below, the indicator goes off when you test-drive the vehicle at 31 mph (50 km/nl.
. Only the drive wheel rotated. The vehicle spun. Electrical noise
1. Visually check for appropriate wheel sensorandpulser installation and condition (see table).
DTCAppropriate Wheel Sensor
12Riqht-front
14Left-front
Riqht-rear
18Left-rear
Ate they installed correctly and not damaged?
YES-Go to step 2,
NO Reinstall or replace the appropriate wheelsensor or pulser,I
Disconnect the ABS control unit 31P connector.
Measure the resistance between the appropriate
wheel sensor ( f) and ( ) circuit terminals (see
table).
ls therc less than 450 Q ?
YES Go to step 1.
NO-Go to step 4.
\\|D
2.
3.
DTCAppropriate Terminal
l*) Side) Side
12 {Rioht-front)No.5:FBS (*No.4:FBS
14 (Left-front)No.7;FLS l*No,6:FLS
16 (Riqht.rear)No.2: RRS (*No. 1:BRS
18 (Left-readNo.9: BLS 1-No.8:RLS