3.
5.
6.
1.
Fuel Cut-off Control
. During deceleration with the throttle valve closed, current to the fuel injectors is cut off to improve fuel economy at
speeds over the following rpm:. D16Y5 engine (M/T):850 rpm. D]6Y5 engine (CVT), D'16Y8 engine (USA M/T): 920 rpm
. Dl6Y8 engine (USA A,/I), D16Y7 engine (USA A,/T);910 rpm
. D16Y8 engine (Canada M/T), D16Y7 engine (canada): 990 rpm
' D16Y8 engine (Canada M/T): 1,000 rpm
. 816A2 engine: 970 rpm
. Fuel cut-off action also takes place when engine speed exceeds 6,900 rpm (D16Y5, D16Y7 engine; D'16Y8 engine:
7,000 rpm. 816A2 engine: 8.100 rpm), regardless of the position of the throttle valve, to protect the engine from
over-rewing. With '99 Dl6Y7 engine (A,/T) and '99 D16Y8 engine (A./T), the PCM cuts the fuel at engine speeds over
5,000 rpm when the vehicle is not moving.
IVC Compressor Clutch Relay
When the ECM/PCM 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 coolant temperature is above 154'F (68'C). the ECM/PCM controls the EVAP purge control solenoid
valve which controls vacuum to the EVAP purge control canister.
Evaporative Emission (EVAP) Purge Control Solenoid Valve*a
When the engine coolant temperature above 154"F (68"C), intake air temperature above 32"F (0'C) and vehicle speed
above 0 mile (0 km/h) or [Ay'C compressor clutch on and intake air temperature above 160"F (41'C)], the ECM/PCM
controls the EVAP purge control solenoid valve which controls vacuum to the EVAP purge control canister.
Exhaust Gas Recirculation (EGR) Control Solenoid Valve*?
When EGR is required for control of oxides of nitrogen (NOx) emissions. the ECM controls the EGR control solenoid
valve which supplies regulated vacuum to the EGR valve
Alternator Control
The system controls the voltage generated at the alternator in accordance with the electrical load and driving mode,
which reduces the engine load to improve the fuel economy.
ECM/PCM Fail-safe/Back-up Functions
1. Fail safe Function
When an abnormality occurs in a signal from a sensor, the ECM/PCM ignores that signal and assumes a pre-pro-
grammed value for that sensor that allows the engine to continue to run.
2. Back-uD Function
When an abnormality occurs in the ECM/PCM itself, the fuel injectors are controlled by a back-up circuit independent
of the system in order to permit minimal driving.
3. Self diagnosis Function lMalfunction Indicator Lamp (MlL)l
When an abnormality occurs in a signal from a sensor, the ECM/PCM supplies ground for the lvllL and stores the DTC
in erasable memory. When the ignition is initially turned on, the ECM/PCM supplies ground for the MIL for two sec-
onds to check the MIL bulb condition.
4. Two Trip Detection Method
To prevent false indications, the Two Trip Detection Method is used for the HO2S, fuel metering-related. idle control
system, ECT sensor, EGR system and EVAP control system self-diagnostic functions. When an abnormality occurs,
the ECM/PCM stores it in its memory. When the same abnormality recurs after the ignition switch is turned OFF and
ON 0l) again, the ECM/PCM informs the driver by lighting the MlL. However, to ease troubleshooting, this function is
cancelled when you jump the service check connector. The MIL will then blink immediately when an abnormality
occurs,
5. Two (or Three) Driving Cycle Detection Method
A "Driving Cycle" consists ot starting the engine. beginning closed loop operation, and stopping the engine. lf misfir-
ing that increases emissions is detected during two consecutive driving cycles, or TWC deterioration is detected dur-
ing three consecutive driving cycles, the ECM/PCM turns the MIL on. However, to ease troubleshooting, this function
is cancelled when you jump the service check connector. The MIL will then blink immediately when an abnormality
occurs.
(cont'd)
1 1-1 05
.1.
Troubleshooting -'96 - 98 Models
Symptom Chart
NOTE;
. Check the engine coolant level. and allow the engine to warm up before troubleshooting.
. Any abnormality must be corrected before continuing the test.
. Because of the precise measurements needed. use a multimeter when testing.
o Before performing any troubleshooting procedures check:- Fuses No. 41 11.5 Al, No. 55 (40 A) in the under-hood fuse/relay box. and No. 17 (7.5 A) in the under-dash fuse/relay
box- Grounds No. G401, G402- Cleanliness and tightness of all connectors
SymptomRomedy
Hot air flow is low.Blower motor runs. but one or more
speeds are inoperative.
Perform the procedures in the flowchart (see page 21-8).
Blower runs properly.Check for the following:. Clogged heater duct. Clogged heater outlet. Incorrect door position
No hot air flow.Blower motor does not run at all,Perform the procedures in the flowchart (see page 21-10).
Blower motor runs.Check for the following:. Clogged heater duct. Clogged blower outlet. Clogged heater valve. Faultv air mix door. Heater valve cable adjustment (see page 21-44). Air mix control cable adiustment (see page 2'l-441. Faulty cooling system thermostat (see section 10). Clogged evaporator (with air conditioning). Frozen evaporator {with air conditioning)
Mode control motor does not run, or one or more modes
are inooerative.
Perform the procedures in the flowchart (see page 21-13).
Recirculation control door does not chanqe between
FRESH and RECIRCULATE.
Perform the procedu.es in the flowchan (see page 21-16).
Both heater and A,/C do not work.Perform the procedures in the flowchart (see page 21-18),
21-6
Power Distribution Schematics
Power Distribution schematics show how power is supplied from the positive battery terminal to
various circuits in the car. Refer to the Power Distribution section to get a more detailed picture
of how power is supplied to the circuit you're working on.
From Battery to lgnition Switch, Fuses, and Relays
Individual circuit schematics begin with a fuse. The first half of Power Distribution, however,
shows the wiring "upstream" between the battery and the fuses.
CYLINDERBLOCK
tl
tlL.lt J
",-* f ]fo,o
i BATTERY
IIII
-
----------------Y-?-
ruse so I ruse as I ruse ga | ' ,s. ,a I =u. - srl ruse aai ruse qr I ruse so I ruse sr i ruse iapowEF csw FUsE Bc, \F,.n .;,cren ooon \coounc cor,r. \sun noor powrnw'NDowf50a {* .i1-;.*"1liT""fi3f* f5# fffi'*"f'* fS?'*
- - -L - - -. ... Ji - -.J.- - - -e- - -l. - - -La - J- - - I - - -
"";%,, Y rtr,' .9 l' -%,t",,vtEw47 I ! See Power Dastribution,w - vH-,alr. lt - pages 10,10and 10-11.
' I ---il 9,1?-l--4F--?-
i I
t.urr, 'rrr.,
t i!?'.,,?"" t::=. l ty::.1----.-
-
i
a I r(op-B) .{Noru3€d) J$ifl#ii Jtocl }3fo**."".o'
t -L - - -L - - -: rJ:e'- - -Ei s+s-r -.Fl-J-Jrr.-.
It-STARTER | !Pase 21 ! t FUSE 31I "rn*i
I f
*
i.Jr;-t
i L_i***'" iL-------J
ilr------!
FUSE /I4 ' FUSE 47 ' FUSE 5{' ' FUSE 51' FUSE 52
rlr
OOOB \COOLING CON. \SUN BOOF FOWER
t3f* f5# fffi*" f'* fs?'*
See Power Dastribution,pages 10'10 and 10-11.
T101
34
ALK
4
GAN
I
I
I
I
I\
\I
I
I
FUSE 8DF POWEF SEAT204
FUSE 6ECU204
FUSE 5A/C CLUICH(FN HEATEDSEAD204
C901 C921 {NotPHoro zz OPTION Used)v/EW22 CONNECTOBSee Power Distnbution, page 10-2.
1
FUSE 4
FADIO104
c901
vlEw22
FUSE 12(BUltNrrGLIGHT)
FUSE 19R/C MIRROF
YEL
7
i-f,r-- 't PowERI uon- I Wlt{DOWi racrs i RELAY. t P^da 1tL-J P;dr1ii-
FUSE 3CONOENSEF FAN RELAYCOOLING FAN RELAY
To Fuses 17, 18, 21,and 24, for details,see Power Windowspage 120.a
ll
ll
ALTER-NATORPage 22
f102
c330
See Power Distribution, pages 10-4 and 10-5.
Fuse
NumberFuse NameAmpsPage
BATTERY
Component or Circult Protected
Power distribution
lgnition switch
INTERIOR LIGHT | 7.5 | 10-10 | DLC, Ceiling light, Trunk light
FI E/M15 i(20 GX) i
i PGM-FI main relay, Fuel injection relay (GX)
Not used
POWER WINDOW| 10-10 | Power window relay
BACK UPStereo radio iuner ('9G'98 mod€ls), Audio unit ('99100
models), Heater control panel, PCM/ECM, TCM (9e'98
cvr)
HEADLIGHT
REAR DEFROSTER I
DOOR LOCK UNIT,
ROOF
i 10-12i Headlights
Not used
Rear window defogger relay
Power door lock control unit (all except '99-'00 models
with keyless), Keyless door lock control unit ('99-'00
models with keyless), Moonroof
i HORN, SrOP Lri 10-13i Horn relay, Brake switch
HAZARDHazard warning switch
OPTIONI 10-13I Security system (option)
i HEATER MOTOR Ii 10-1 i Blower motor relay
(CONDENSER FAN)
COOLING FANl1o-1
Condenser Jan relay, A'lC compressor clutch relay
Radiator tan relay
&5