1998 HONDA INTEGRA air conditioning

Engine Ramoval/lnstallation
(cont'dl
13. Remove the engine wire harness connectors, termi-
nal and clamps on the left side ot engine compan-
menr,
6 x 1.0 mm9.8 N.m 11.0 kgl.m,7.2 tbt.ttl
14. Remove the cruise control actuator.
I x 1.25 mm24 N.m 12.4 kgt.m,17 tbt.ft)
5-6
A/C COMPRESSOR EELT
\
l.15.
to.
Remove the engine ground cable at the body end.
Remove the adjusting bolt and mounting bolts, then
remove the power steering (P/S) pump belt and
pump.
. Do not disconnect the P/S hoses.
MOUNTING BOLTSI x 1.25 mm24 N.m 12.4 kgt'm, 17 lbl.ft)
Loosen the idler pulley bolt and adjusting bolt, then
remove the air conditioning (Ay'C) compressor belt.
IDLER PULLEY BOLT10 x 1.25 mm/14 N'm 14.5 kgf.m, 33 lbt'frl
I
I
't7.

PGM-FI System
System Description
ENGINE CONTROL MODULE (ECM)OUTPUTS
*1: USA*2: 818C1 engine*3: A,/T*4: 818C1, 818C5 engines
PGM-FI Sy3tem
The PGM-Fl system on this model is a sequential multiport fuel injection system.
Fuel lniector Timing and Duration
The ECM contains memories for the basic discharge durations at various engine speeds and manifold pressures. The
basic discharge duration, after being read out from the memory. is further modified by signals sent from various sensors
to obtain the final discharge duration.
ldle Air Control
ldle Ai. Control Valve (lAC Valve)
When the engine is cold, the Ay'C compressor is on. the transmission is in gear (Ay'T only)the brake pedal is depressed, the
P/S load is high, or the alternator is charging, the ECM controls current to the IAC Valve to maintain correct idle speed.
lgnition Timing Control
. The ECM contains memories for basic ignition timing atvarious engine speeds and manifold pressures, lgnitiontiming
is also adjusted for engine coolant temperature.
. AKnockControl System isadoptedwhich sets the ideal ignition timing for the octane n um ber of gasoline used*r,
Other Control Functions
L Starting Control
When the engine is started, the ECM provides a rich mi{ure by increasing fuel injector duration.
2. Fuel PumD Control
. When the ignition switch is initially turned on, the ECM supplies ground to the PGM-FI main relay that supplies
current to the fuel pump for two seconds to pressurize the fuel system.
. When the engine is running, the ECM supplies ground to the PGM-FI main relay that supplies current to the fuel
DUmO.
. When the engine is not running and the ignition is on. the ECM cuts ground to the PGM-FI main relay which cuts
current to the fuel oumo.
INPUTS
TDc/CKP/CYP Sensor
CKF Sensor
MAP Sensor
ECT Sensor
IAT Sensor
TP Sensor
HO2S
VSS
BARO Sensor
ELD*1
Starter Signal
ALT FR Signal
Air Conditioning Signal
A,/T Gear Position Signal*3
Battery Voltage (lGN.1)
Brake Switch Signal
PSP Switch Signal*'
Knock Sensor*1
VTEC Pressure Switch*4
Fuel Tank Prssure Sensor
Fuel InjectorTiming and Duration
Electronic ldle Control
Other Control Functions
lgnition Timing Control
ECM Back-uD Functions
Fuel-lnjectors
PGM-Fl Main Relay (Fuel Pump)
MIL
IAC Valve
A,/C Compressor Clutch Relay
Radiator Fan Belay*1
Condenser Fan Relay
ALT*1
rcM
EVAP Purge Control Solenoid
Valve
H02S Heater
VTEC Solenoid Valve*'
IAB Control Solenoid Valve*,
EVAP Bypass Solenoid Valve
EVAP Control Canister Vent
Shut Valve
11-48

3.Fuel Cut-off Control
. Du ring dece leration with the th rottle va lve closed, cu rrent to the fuel injectors is cutoffto improvefuel economyat
speeds over following rpm:. B'1881 engine: 970 rpm {Canada model: 1.050 rpm). B18C1 engine:970 rpm {Canada model: 1.050 rpm). 818C5 engine: 1,300 rpm (Canada model: 1,400 rpm)
. Fuel cut-off action also takes place when engine speed exceeds 7,000 rpm (B'1881 engine), 8.100 rpm (818C1
engine) or 8,600 rpm (818C5 engine), regardless ol the position of the thronle valve, to protect the engine from
over-revving.
A,,/C ComDressor Clutch Relav
When the ECM receives a demand for cooling from the air conditioning system, it delays the compressor from being
energized, and enriches the mixture to assure smooth transition to the A,/C mode.
Evaporative Emission (EVAP) Purge Control Solenoid Valve
When the engine coolanl temperature is above '154'F (68'C) and the air conditioner on. the ECM controls the EVAPpurge control solenoid valve which controls vacuum to the EVAP purge control canister.
Intake Air Eypass (lAB) Control Solenoid Valve*a
When the engine rpm is below 5,750 rpm, rhe IAB control solenoid valve is activated by a signal from the ECM, intake
air flows through the long intake path, then high torque is delivered. At speeds higher than 5,750 rpm, the solenoidvalve is deactivated by the ECM, and intake air flows through the short intake path in order to reduce the resistance in
airflow.
Sell-diagnosis Function lMalfunction Indicator Lamp {MlL)lWhen an abnormality occurs in a signal from a sensor, the ECM supplies ground for the MIL and stores the code in
erasable memory. When the ignition is initially turned on, the ECM supplies ground for the N4lL tor two seconds to
check the MIL bulb condition.
Two Driving Cycle Detection Method
To prevent false indications, the Two Driving Cycle Detection Method is used for the HO2S, fuel metering-related, idle
control system, ECT sensor, TWC and EVAP control system and other self-diagnostic functions, When an abnormality
occurs, the ECM stores it in its memory. When the same abnormality recurs after the ignition switch is turned OFFand ON (ll)again, the ECM informs the driver by lighting the MlL.
However, to ease troubleshooting, this function is cancelled when you shon the service check connector. The MIL will
then blink immediately when an abnormality occurs.
4.
5.
6.
3.
4.
ECM Fail-safe/8ack.up F0nctions
1. Fail-sate Function
When an abnormality occurs in a signal from a sensor, the ECM ignores that signal and assumes a pre-programmed
value for that sensor that allows the enqine to continue to run.
2. Back-uo Function
When an abnormality occurs in the ECM itself, the fuel injectors are controlled by a back-up circuit independent of the
system in order to permit minimal driving.
11-49

2.
1.
1.
2.
After the engine stans, the IAC valve opens for a certain time. The amount ol air is increased to raise the idle speed
about 150 - 300 rpm.
When the coolant temperature is low, the IAC valve is opened to obtain the proper fast idle speed. The amount of
bypassed air is thus controlled in relation to the engine coolant temperature.
IDLE SPEEDtrpm,
ENGINECOOLANT TEMPERATURE
140
50
104
40
-1 32
-20 0
176 ('F)
80 fcl
When the idle speed is out of specification and the scan tool does not indicate Diagnostic Trouble Code (DTC) P0505
or P'1508, check the following items:. Adiust the idle speed (see page '11-111)
' ALT FR signal (see page 11-101). Air conditioning signal {seepage'11-102)' Brake switch signal (seepagell-104)
. Starter switch signal (see page 11-1051. A,4 gear position signal (see page 1l 106) (A"/T)
. PSP switch signal (see page 11-108) (USA)
. Fast idle thermo valve (see page 11-110). Hoses and connections. IAC valve and its mounting O rings
ll the above items are normal, substitute a known-good IAC valve and readjust the idle speed (see page 'l I -1 1 l).
lf the idle speed still cannot be adjusted to specification (and the scan tool does not indicate DTC P0505 or P1508) after
IAC valve replacement, substitute a known-good ECM and recheck. lf symptom goes away, replace the original ECM.
11-97

ldle
Air
Gontrol System
Gonditioning Signal
\
This signals the ECM when there is a demand for cooling from the air conditioning system'
ECM CONNECTORS
a l32Pl
LGl(BRN/BLKI
c t31Pt
ACSIBLU/REDI
wire side of femal€ torminals
;
L
LGI
JUMPERWIRE
ACS IBLU/REDI
Check lor.3hort in thG wira(ACS lino):1. Turn the ignition switch OFF.2. Disconnect the A/C pressure
switch connector and A/Cdiode connector,3. Turn the ignition switch ON (ll).
4. Measu re voltage betwo€nECM connector terminals C5and A9.
Ch.ck to.. rhorl in th. wir. IACSlincl:1. Turn the ignition switch OFF.2. Disconnect the ECM connec-tor C (31P).
3. Ch6ck {or continuity betwe€n
body ground tnd ECM con-nector terminal C5.
lsthere approx.5 V?
Rapair rhort In tho wira batwaon
th. EcM {c5l and thc A/c pre.-
sur. rwitch ot A/C diod.,
- Subtlilut I known{ood Ecttllnd raahack. lf prtactibad voft-
rgo ir now avaihbla, tcplacalh. originll ECM.- Saa tha air condhiond in.plction 1... r.ction 221.
Check lor an opan in th€ wi.a(ACC lin.l:'1. Turn the ignition switch OFF.2. Reconnect th6 A,/C pressure
switch connector and A/Cdiode connector.3. Turn the ignilion switch ON (ll).
4. Momentarily connect ECMconnector terminals A'17 andAg wkh a iumper wire severaltimes,
(To page 11"103)
IBRN/BLKI
Ial,/l l8 I r0 I rl
12't516 11alrslzo ,/ l4l a3 | 2.
aa2621zel dt
IBLK/REDI
11-102
\

(From page t 1'102)
Ch6ck {or an op6n in the wireIACC linel:Mo m enta rily connect the A/Cclutch relay 4P connector termi-nal No. 4 to body ground with a,umper wire several times.
ls there a clicking noise fromthe A,/C compressor clutch?
ls there a clicking noise fromthe 4,./C compressor clutch?See air conditione. insoection{s€e section 22).
Repai. op6n in the wire betwe€ntho ECM lA17l and the A/C clutch
Check tor the oparation of theA/C:1. Start the eogine.2. Turn the blower switch ON.3. Turn the !y'C switch ON.
Check lor sn open in th6 wireIACS line):Measure voltage between ECMconnector terminals C5 and A9,
Air conditioning signal i3 OK.Repafu open in the wire betweenthe ECM {C5} and th€ A/C D.es-sure switch or A/C diode.
ls voltage less than 1.0 V?
- Substitute e known-good ECM.nd .echeck. lf 3ymptom/indi-cation goes away, rcplaco th€original ECM.- 56€ the air conditionor inspcc-tion {3eo soction 221.
UNDER HOOD FUSE/RELAYBOX 9P CONNECTOR tC216)
JUMPERWIREACC {SLK/RED)Wire side of temale- terminals
A {32P)
LGl(BRN/BLKI
ECM CONNECTORS
Wire side of female terminals
c (31P)
ACS{BLU/RED}
I
'1.1-103

Terminal NumberSignalDescriptionMaasuring Conditlons/Tarminal Voliage
424ACCLAir conditioning (Ay'C) clutch relay
control
With A,/C comDressor ON: 0 V
With Ay'C compressor OFF: Battery voltage
A25tG1Power supply systemWith ignition switch ON (ll)r 12 V
426LG1Ground
B1Not used
82BAROS SBarometric pressure sensor signal
input
With ignition switch ON (ll) and depending on
barometric pressure: Approx. 3 V
B3ECTEngine coolant temperature sen-
sor signal input
With ignition switch ON (ll) and depending on
engine coolant tem perature: Approx. 0.1 - 4.8 V
B4TPSThrottle position sensor signal
input
With ignition switch ON (ll) 8nd throttle fully
open: 4.14 - 4.82 V
With ignition switch ON (ll) and throttle fully
closed: 0.44 - 0.56 V
B5VSSVehicle speed sensor signal inputWith ignition switch ON (ll) and front wheels
rotating; Pulsing signal
B6AFSBUpshifvdownshift comparative
signal output
With engine idling: 0 V
At uDshift or downshift: 5 V for an instant
B7AFSAUpshifvdownshift com parative
srgnal output
With engine idling: 0 V
At upshift or downshift: 5 V for an instant
B8NCSGCountershaft speed sensor signal
ground
Always: 0 V
B9NCCountershaft speed sensor signal
Input
Depending on vehicle speed: Pulsing signal
When vehicle is stopped:0 V
B10NMMainshaft speed sensor signal
input
Depending on vehicle speed: Pulsing signal
When vehicle is stoDoed: 0 V
811Not used
812STOP SWBrake switch signal inputWith ignition switch ON {ll) and b.ake pedal
depressed: Battery voltage
With ignition switch ON (lll and brake pedal
released:0 V
813Not used
814scsTiming adjustment
service check signal
With ignition switch ON (ll) and service check
connector oDen:5 V
With ignition switch ON (ll) and service check
connector connected with special tool: 0 V
815Not used
816Not used
817NMSGMainshaft speed sensor signalgroundAlways: 0 V
818Not used
819FASShift acknowledge inputWith engine idling: 5 V
At upshift or downshift: 0 V for an instant
820VBEF+5 V referenceWith ignition switch ON {lll: Approx. 5 V
82'lNot used
Not used
14-49

SYMPTOMREMEDY
Hot air tlow is low.Blower motor runs, but one or more
speeds are inoperative.
Follow the flowchart (see page 21-9).
Blower runs propetly.Check for the following:. Clogged heater duct
. Clogged heater outlet
. Incorrect door Position
No hot air tlowBlower motor does not run at all.Follow the flowchart {see page 21-11}
Blower motor runs.Check for the following:
. clogged heater duct
. Clogged blower outlet. Clogged heatet valve
. Faultv air mix door
. Heater valve cable adjustment lsee page 21-27].
. Air mix control cable adiustment {see page 21-27)
. Faulty thermostat (see section 10)
. Clogged evsporator (with air conditioning)
. Frozen evaDorator (with air conditioning)
Mode control motor does not run, or one or more mooes are
inoDeratave.
Follow the flowchart (see page 21-14).
Recirculation control door does not change between FRESH
and RECIRCULATE.
Follow the flowchart {see page 21-17).
Troubleshooting
Symptom Chart
NOTE: Check the engin€ coolant level and allow the engine to warm up before troubleshooting'
21-8
v