ENGINE CONTROL COMPONENT PARTS/CONTROL
SYSTEMS APPLICATION
NLEC0034S02
ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOS-
TIC RESULTS
D ATA
MONI-
TORD ATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STA-
TUSDTC
WORK
SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
INPUTCamshaft position sensor
(PHASE)XEngine
speed
XEngine
speed
XEngine
speed
X
Crankshaft position sensor
(POS)X*3
Mass air flow sensor X X X
Engine coolant temperature
sensorXXX XX
Heated oxygen sensor 1
(front)X X X X*3 X*3
Heated oxygen sensor 2
(rear)X*3 X X X*3 X*3
Vehicle speed sensor X X X X
Throttle position sensor X X X
EGR temperature sensor
(where fitted)X*3 X X
Intake air temperature sen-
sorX*3 X X X
Knock sensor X
Ignition switch (start signal) X X
Closed throttle position
switch
(where fitted)X*3 X X
Closed throttle position
switch (throttle position sen-
sor signal)XX
Air conditioner switch X X
Park/Neutral position (PNP)
switchX*3 X X
Power steering oil pressure
switchXX
Electrical load X X
Heater fan switch X X
Battery voltage X X
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG18DE
CONSULT-II (Cont'd)
EC-83
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
HO2S2 MNTR (B1)
[RICH/LEAN]j+Display of heated oxygen sensor 2 (rear) sig-
nal:
RICH ... means the amount of oxygen after
three way catalyst is relatively small.
LEAN ... means the amount of oxygen after
three way catalyst is relatively large.+When the engine is stopped, a cer-
tain value is indicated.
VHCL SPEED SE
[km/h] or [mph]jj+The vehicle speed computed from the vehicle
speed sensor signal is displayed.
BATTERY VOLT [V]j+The power supply voltage of ECM is dis-
played.
THRTL POS SEN [V]jj+The throttle position sensor signal voltage is
displayed.
INT/A TEMP SE
[ÉC] or [ÉF]j+The intake air temperature determined by the
signal voltage of the intake air temperature
sensor is indicated.
EGR TEMP SEN [V]
(where fitted)jj+The signal voltage of the EGR temperature
sensor is displayed.
START SIGNAL
[ON/OFF]jj+Indicates [ON/OFF] condition from the starter
signal.+After starting the engine, [OFF] is
displayed regardless of the starter
signal.
CLSD THL POS
[ON/OFF]jj+Indicates idle position [ON/OFF] computed by
ECM according to the throttle position sensor
signal.
CLSD THL/P SW
[ON/OFF]
(where fitted)j+Indicates mechanical contact [ON/OFF] con-
dition of the closed throttle position switch.
AIR COND SIG
[ON/OFF]jj+Indicates [ON/OFF] condition of the air condi-
tioner switch as determined by the air condi-
tioning signal.
P/N POSI SW
[ON/OFF]jj+Indicates [ON/OFF] condition from the PNP
switch signal.
PW/ST SIGNAL
[ON/OFF]jj+Indicates [ON/OFF] condition of the power
steering oil pressure switch determined by
the power steering oil pressure switch signal.
LOAD SIGNAL
[ON/OFF]jj+Indicates [ON/OFF] condition from the electri-
cal load signal and/or lighting switch.
ON ... rear defogger is operating and/or light-
ing switch is on.
OFF ... rear defogger is not operating and
lighting switch is not on.
IGNITION SW
[ON/OFF]j+Indicates [ON/OFF] condition from ignition
switch.
HEATER FAN SW
[ON/OFF]j+Indicates [ON/OFF] condition from the heater
fan switch.
INJ PULSE-B1
[msec]j+Indicates the actual fuel injection pulse width
compensated by ECM according to the input
signals.+When the engine is stopped, a cer-
tain computed value is indicated.
IGN TIMING [BTDC]j+Indicates the ignition timing computed by
ECM according to the input signals.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG18DE
CONSULT-II (Cont'd)
EC-87
Basic InspectionNLEC0564MODELS WITH THROTTLE POSITION SWITCH AND
THROTTLE OPENER
NLEC0564S01Precaution:
Perform Basic Inspection without electrical or mechanical
loads applied;
+Headlamp switch is OFF,
On vehicle equipped with daytime light systems, set lighting
switch to the 1st position to light only small lamps.
+Air conditioner switch is OFF,
+Rear window defogger switch is OFF,
+Steering wheel is in the straight-ahead position, etc.
1 INSPECTION START
1. Check service records for any recent repairs that may indicate a related problem, or a current need for scheduled
maintenance.
2. Open engine hood and check the following:
+Harness connectors for improper connections
+Vacuum hoses for splits, kinks and improper connections
+Wiring for improper connections, pinches and cuts
+Air cleaner clogging
+Hoses and ducts for leaks
SEF983U
©GO TO 2.
2 CHECK THROTTLE OPENER OPERATION-I
Confirm that there is a clearance between throttle drum and stopper.
SEF850Y
OK or NG
OK©GO TO 4.
NG©GO TO 3.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG18DE
Basic Inspection
EC-99
MODELS WITHOUT THROTTLE POSITION SWITCH AND
THROTTLE OPENER
NLEC0564S02Precaution:
Perform Basic Inspection without electrical or mechanical
loads applied;
+Headlamp switch is OFF,
On vehicle equipped with daytime light system, set lighting
switch to the 1st position to light only small lamps.
+Air conditioner switch is OFF,
+Rear window defogger switch is OFF,
+Steering wheel is in the straight-ahead position, etc.
1 INSPECTION START
1. Check service records for any recent repairs that may indicate a related problem, or a current need for scheduled
maintenance.
2. Open engine hood and check the following:
+Harness connectors for improper connections
+Vacuum hoses for splits, kinks and improper connections
+Wiring for improper connections, pinches and cuts
+Air cleaner clogging
+Hoses and ducts for leaks
SEF983U
©GO TO 2.
2 CHECK THROTTLE DRUM OPERATION-I
Confirm that throttle drum is in contact with the stopper.
OK or NG
OK (with CONSULT-II)©GO TO 5.
OK (without CONSULT-
II)©GO TO 8.
NG©GO TO 3.
3 CHECK ACCELERATOR WIRE INSTALLATION
Check accelerator wire for slack.
OK or NG
OK©GO TO 4.
NG©Adjust accelerator wire. Refer to FE section, ªAdjusting Accelerator Wireº.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG18DE
Basic Inspection (Cont'd)
EC-114
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Crankshaft position sensor (POS)
circuit22EC-295
Camshaft position sensor
(PHASE) circuit3 2 3 EC-302
Mass air flow sensor circuit11222 22 2EC-154
Heated oxygen sensor 1 (front)
circuit1232 22 2EC-184,
192
Engine coolant temperature sen-
sor circuit112323223 2EC-169,
171
Throttle position sensor circuit 1 222222 2EC-175
Incorrect throttle position sensor
adjustment31 11111 1EC-99
Vehicle speed sensor circuit 2 3 3 3 EC-338
Knock sensor circuit 2 3 EC-291
ECM 22333333333EC-358,
123
Start signal circuit 2EC-512
PNP switch circuit 3 3 3 3 3 EC-402
Power steering oil pressure
switch circuit2 3 3 EC-524
Electrical load signal circuit 3 3 EC-535
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG18DE
Symptom Matrix Chart (Cont'd)
EC-125
MONITOR ITEM CONDITION SPECIFICATION
PW/ST SIGNAL+Engine: After warming up, idle
the engineSteering wheel in neutral position
(forward direction)OFF
The steering wheel is turned ON
LOAD SIGNAL+Engine: runningRear window defogger or headlamp
ªONºON
Except the above OFF
IGNITION SW+Ignition switch: ON®OFF ON®OFF
HEATER FAN SW+Heater fan switch is ªONº ON
+Heater fan switch is ªOFFº OFF
INJ PULSE-B1+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 2.0 - 3.5 msec
2,000 rpm 1.5 - 3.5 msec
IGN TIMING+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 8É BTDC
2,000 rpm Approx. 30É BTDC
CAL/LD VALUE+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle Not used
2,500 rpm Not used
ABSOL TH´P/S+Engine: Idle Throttle valve fully closed 0.0É
+Ignition switch: ON
(Engine stopped)Throttle valve fully opened Approx. 80É
MASS AIRFLOW+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: N
+No-loadIdle 1.0 - 4.0 g´m/s
2,500 rpm 5.0 - 10.0 g´m/s
IACV-AAC/V+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 5 - 25 steps
2,000 rpm Ð
PURG VOL C/V+Engine: After warming up
+No-loadIdle 0%
Revving engine Ð
EGR VOL CON/V
(where fitted)+Engine: After warming up
+Shift lever: ªNº
+No-loadIdle 0 step
Revving engine up to 3,000 rpm
quickly1 - 10 steps
SWRL CONT S/V
(where fitted)+Engine speed: IdleEngine coolant temperature is
between 15ÉC (59ÉF) to 40ÉC
(104ÉF)ON
Engine coolant temperature is above
40ÉC (104ÉF)OFF
INT/V SOL-B1+Engine: After warming up
+Lift up drive wheelsIdle OFF
Suitable gear position except ªNº
and revving engineON (Momentarily)
AIR COND RLY+Air conditioner switch: OFF®ON OFF®ON
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG18DE
CONSULT-II Reference Value in Data Monitor Mode (Cont'd)
EC-129
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
35
36
37
38L/W
PU
L/R
GY/RIgnition signal (No. 1)
Ignition signal (No. 2)
Ignition signal (No. 3)
Ignition signal (No. 4)[Engine is running]
+Warm-up condition
+Idle speed0 - 0.2V
SEF971W
[Engine is running]
+Engine speed is 2,000 rpm0.2 - 0.4V
SEF972W
40 Y/PUThrottle position switch
(Closed position)
(where fitted)[Engine is running]
+Accelerator pedal releasedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Accelerator pedal depressedApproximately 0V
41 B/Y Start signal[Ignition switch ªONº]Approximately 0V
[Ignition switch ªSTARTº]9 - 12V
42 G/OR PNP switch[Ignition switch ªONº]
+Gear position is ªNeutral positionºApproximately 0V
[Ignition switch ªONº]
+Except the above gear positionApproximately 5V
43 B/R Ignition switch[Ignition switch ªOFFº]0V
[Ignition switch ªONº]BATTERY VOLTAGE
(11 - 14V)
44 L/R Air conditioner switch[Engine is running]
+Both air conditioner switch and blower switch
are ªONº (Compressor operates)Approximately 0V
[Engine is running]
+Air conditioner switch is ªOFFºApproximately 5V
46 PU/WPower steering oil pres-
sure switch[Engine is running]
+Steering wheel is fully turnedApproximately 0V
[Engine is running]
+Steering wheel is not turnedApproximately 5V
48 B ECM ground[Engine is running]
+Idle speedEngine ground
50 L/BElectrical load signal
(Headlamp and
Rear defogger)[Engine is running]
+Headlamp switch or rear defogger switch is
ªONºBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Headlamp switch and rear defogger switch are
ªOFFºApproximately 0V
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG18DE
ECM Terminals and Reference Value (Cont'd)
EC-137
DescriptionNLEC1271The specification (SP) value indicates the tolerance of the value that is displayed in ªDATA MONITOR (SPEC)º
mode of CONSULT-II during normal operation of the Engine Control System. When the value in ªDATA MONI-
TOR (SPEC)º mode is within the SP value, the Engine Control System is confirmed OK. When the value in
ªDATA MONITOR (SPEC)º mode is NOT within the SP value, the Engine Control System may have one or
more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the
MIL.
The SP value will be displayed for the following three items:
+B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board cor-
rection)
+A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)
+MAS A/F SE-B1 (The signal voltage of the mass air flow sensor)
Testing ConditionNLEC1272+Vehicle driven distance: More than 5,000 km (3,100 miles)
+Barometric pressure: 101.3 kPa (760.0 mmHg, 29.92 inHg)±3 kPa (22.5 mmHg, 0.89 inHg)
+Atmospheric temperature: 20 - 30ÉC (68 - 86ÉF)
+Engine coolant temperature: 75 - 95ÉC (167 - 203ÉF)
+Transmission: Warmed-up*1
+Electrical load: Not applied*2
+Engine speed: Idle
*1: For M/T models, drive vehicle for 5 minutes after the engine is warmed up to normal operating tempera-
ture.
*2: Rear window defogger switch, air conditioner switch, lighting switch are ªOFFº. Cooling fans are not oper-
ating. Steering wheel is straight ahead.
SEF601Z
Inspection ProcedureNLEC1273NOTE:
Perform ªDATA MONITOR (SPEC)º mode in maximum scale dis-
play.
1. Perform ªBasic Inspectionº, EC-99.
2. Confirm that the testing conditions indicated above are met.
3. Select ªB/FUEL SCHDLº, ªA/F ALPHA-B1º, ªA/F ALPHA-B2º
and ªMAS A/F SE-B1º in ªDATA MONITOR (SPEC)º mode with
CONSULT-II.
4. Make sure that monitor items are within the SP value.
5. If NG, go to ªDiagnostic Procedureº, EC-142.
TROUBLE DIAGNOSIS Ð SPECIFICATION VALUEQG18DE
Description
EC-141