Air Conditioning Cut Control
DESCRIPTIONNJEC0614Input/Output Signal ChartNJEC0614S01
Sensor Input Signal to ECM ECM Function Actuator
Air conditioner switch Air conditioner “ON” signal
Air conditioner
cut controlAir conditioner relay Accelerator position sensor Accelerator valve opening angle
Vehicle speed sensor Vehicle speed
Engine coolant temperature sensor Engine coolant temperature
System DescriptionNJEC0614S02This system improves acceleration when the air conditioner is used.
When the accelerator pedal is fully depressed, the air conditioner is turned off for a few seconds.
When engine coolant temperature becomes excessively high, the air conditioner is turned off. This continues
until the engine coolant temperature returns to normal.
Fuel Cut Control (at no load & high engine
speed)
DESCRIPTIONNJEC0615Input/Output Signal ChartNJEC0615S01
Sensor Input Signal to ECM ECM Function Actuator
Vehicle speed sensor Vehicle speed
Fuel cut controlElectronic control fuel
injection pump Accelerator position switch Accelerator position
Crankshaft position sensor (TDC) Engine speed
If the engine speed is above 2,800 rpm with no load (for example, in neutral and engine speed over 2,800
rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies based on engine speed.
Fuel cut will operate until the engine speed reaches 1,500 rpm, then fuel cut is cancelled.
NOTE:
This function is different from deceleration control listed under “Fuel Injection Control System”, EC-17.
SEF440Z
Crankcase Ventilation System
DESCRIPTIONNJEC0616In this system, blow-by gas is sucked into the air duct after oil
separation by oil separator in the rocker cover.
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ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTIONYD
Air Conditioning Cut Control
EC-19
ENGINE CONTROL COMPONENT PARTS/CONTROL
SYSTEMS APPLICATION
=NJEC0629S02
ItemDIAGNOSTIC TEST MODE
SELF-DIAG
RESULTSDATA MONI-
TORACTIVE TEST
ENGINE CONTROL COMPONENT PARTS
INPUTEngine coolant temperature sensor X X
Vehicle speed sensor X X
Accelerator position sensor X X
Accelerator position switch X X
Crankshaft position sensor (TDC) X X
Ignition switch (start signal) X
Park/Neutral position (PNP) switch (where fitted) X
Battery voltage X X
Mass air flow sensor X X
Stop lamp switch X X
OUTPUTGlow relayXX
EGR volume control valve X X
Cooling fan relay X X X
X: Applicable
SELF-DIAGNOSTIC MODENJEC0629S03Regarding items detected in “SELF-DIAG RESULTS” mode,
refer to “TROUBLE DIAGNOSIS — INDEX”, EC-4.
DATA MONITOR MODENJEC0629S04
Monitored item
[Unit]ECM
input
signalsMain
signalsDescription Remarks
CKPS·RPM (TDC)
[rpm]The engine speed computed from the
crankshaft position sensor (TDC) signal
is displayed.
CMPS·RPM·PUMP
[rpm]The engine speed computed from the
pulse signal sent from electronic control
fuel injection pump is displayed.
COOLAN TEMP/S
[°C] or [°F]The engine coolant temperature (deter-
mined by the signal voltage of the
engine coolant temperature sensor) is
displayed.When the engine coolant temperature
sensor is open or short-circuited, ECM
enters fail-safe mode. The engine cool-
ant temperature determined by the ECM
is displayed.
VHCL SPEED SE
[km/h] or [mph]The vehicle speed computed from the
vehicle speed sensor signal is dis-
played.
FUEL TEMP SEN
[°C] or [°F]The fuel temperature (sent from elec-
tronic control fuel injection pump) is dis-
played.
ACCEL POS SEN
[V]The accelerator position sensor signal
voltage is displayed.
OFF ACCEL SW
[ON/OFF]Indicates [ON/OFF] condition from the
accelerator position switch signal.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD
CONSULT-II (Cont’d)
EC-40
Monitored item
[Unit]ECM
input
signalsMain
signalsDescription Remarks
SPILL/V [°CA] The control position of spill valve (sent
from electronic control fuel injection
pump) is displayed.
BATTERY VOLT [V] The power supply voltage of ECM is
displayed.
P/N POSI SW*1
[ON/OFF] (where
fitted)Indicates [ON/OFF] condition from the
park/neutral position switch signal.
START SIGNAL
[ON/OFF]Indicates [ON/OFF] condition from the
starter signal.After starting the engine, [OFF] is dis-
played regardless of the starter signal.
BRAKE SW
[ON/OFF]Indicates [ON/OFF] condition from the
stop lamp switch signal.
BRAKE SW2
[ON/OFF]Indicates [ON/OFF] condition from the
brake pedal position switch signal.
IGN SW
[ON/OFF]Indicates [ON/OFF] condition from igni-
tion switch signal.
MAS AIR/FL SE [V] The signal voltage of the mass air flow
sensor is displayed.When the engine is stopped, a certain
value is indicated.
INT/A VOLUME [mg/] The intake air volume computed from
the mass air flow sensor signal is dis-
played.
F/CUT SIGNAL
[ON/OFF]The [ON/OFF] condition from decelera-
tion fuel cut signal (sent from electronic
control fuel injection pump) is displayed.
O F F ···F u e l i s c u t o ff .
O N ···F u e l i s n o t c u t o ff .
GLOW RLY
[ON/OFF]The glow relay control condition (deter-
mined by ECM according to the input
signal) is displayed.
COOLING FAN
[LOW/HI/OFF]Indicates the control condition of the
cooling fans (determined by ECM
according to the input signal).
LOW ... Operates at low speed.
HI ... Operates at high speed.
OFF ... Stopped.
BARO SEN [kPa] The barometric pressure (determined by
the signal voltage from the barometric
pressure sensor built into the ECM) is
displayed.
EGR VOL CON/V
[step]Indicates the EGR volume control value
computed by the ECM according to the
input signals.
The opening becomes larger as the
value increases.
*1: On models not equipped with park/neutral position (PNP) switch, “OFF”is always displayed regardless of gear shift position.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD
CONSULT-II (Cont’d)
EC-41
ACTIVE TEST MODENJEC0629S05
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
COOLING FANIgnition switch: ON
Operate the cooling fan at
“LOW”, “HI” speed and turn
“OFF” using CONSULT-II.Cooling fan moves at “LOW”, “HI”
speed and stops.Harness and connector
Cooling fan motor
Cooling fan relay
EGR VOL
CONT/VIgnition switch: ON
Change EGR volume control
valve opening step using CON-
SULT-II.EGR volume control valve makes
an operating sound.Harness and connector
EGR volume control valve
GLOW RLYIgnition switch: ON (Engine
stopped)
Turn the glow relay “ON” and
“OFF” using CONSULT-II and
listen to operating sound.Glow relay makes the operating
sound.Harness and connector
Glow relay
SEF373Y
SEF707X
REAL TIME DIAGNOSIS IN DATA MONITOR MODENJEC0629S06CONSULT-II has two kinds of triggers and they can be selected by
touching “SETTING” in “DATA MONITOR” mode.
1) “AUTO TRIG” (Automatic trigger):
The malfunction will be identified on the CONSULT-II screen in
real time.
In other words, DTC will be displayed if the malfunction is
detected by ECM.
At the moment a malfunction is detected by ECM, “MONITOR”
in “DATA MONITOR” screen is changed to “Recording Data ...
xx%” as shown at left, and the data after the malfunction detec-
tion is recorded. Then when the percentage reached 100%,
“REAL-TIME DIAG” screen is displayed. If “STOP” is touched
on the screen during “ Recording Data ... xx%”, “REAL-TIME
DIAG” screen is also displayed.
The recording time after the malfunction detection and the
recording speed can be changed by “TRIGGER POINT” and
“Recording Speed”. Refer to CONSULT-II OPERATION
MANUAL.
2) “MANU TRIG” (Manual trigger):
DTC will not be displayed automatically on CONSULT-II screen
even though a malfunction is detected by ECM.
DATA MONITOR can be performed continuously even though
a malfunction is detected.
Use these triggers as follows:
1) “AUTO TRIG”
While trying to detect the DTC by performing the “DTC Confir-
mation Procedure”, be sure to select to “DATA MONITOR
(AUTO TRIG)” mode. You can confirm the malfunction at the
moment it is detected.
While narrowing down the possible causes, CONSULT-II
should be set in “DATA MONITOR (AUTO TRIG)” mode, espe-
cially in case the incident is intermittent.
When you are inspecting the circuit by gently shaking (or twist-
ing) the suspicious connectors, components and harness in
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD
CONSULT-II (Cont’d)
EC-42
SYSTEM — ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO
START/RESTART
(EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGWarranty symptom code AA AB AC AD AE AF
ENGINE CONTROL
EGR volume control valve circuit*a, *b
EC-197
*c 1 1 1 *6
Glow relay circuit*a 1111
EC-188*7
*b*8
ECM relay (Self-shutoff) circuit*a 1 111
EC-177
*b*9
ECM, Connector circuit *a, *b 2 2 22222222222EC-175,
11 6
Air conditioner relay circuit*a
EC-212*10
*b 1 *11
Air conditioner switch circuit*a, *c
EC-212*11
*b*12
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*a: Open
*b: Short
*c: Ground short
*d: Noise
*6: Does not stop operating.
*7: Glow lamp does not turn on.
*8: Glow lamp does not turn off.
*9: Ground short makes engine unable to stop.
*10: Air conditioner does not operate.
*11: Air conditioner does not stop operating.
*12: Air conditioner does not work.
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TROUBLE DIAGNOSIS — GENERAL DESCRIPTIONYD
Symptom Matrix Chart (Cont’d)
EC-61
SYSTEM — ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator illuminates.
Can be detected by CONSULT-II?BLACK SMOKE
WHITE SMOKEWarranty symptom code AG AH AJ AK AL AM AP HA
ENGINE CONTROL
EGR volume control valve circuit*a, *b
EC-197
*c 1 *6
Glow relay circuit*a 1
EC-188*7
*b*8
ECM relay (Self-shutoff) circuit*a
EC-177
*b*9
ECM, Connector circuit *a, *b22222222222EC-175,
11 6
Air conditioner relay circuit*a
EC-212*10
*b*11
Air conditioner switch circuit*a, *c
EC-212*11
*b*12
1 - 5: The numbers refer to the order of inspection.
*a: Open
*b: Short
*c: Ground short
*d: Noise
*6: Does not stop operating.
*7: Glow lamp does not turn on.
*8: Glow lamp does not turn off.
*9: Ground short makes engine unable to stop.
*10: Air conditioner does not operate.
*11: Air conditioner does not stop operating.
*12: Air conditioner does not work.
TROUBLE DIAGNOSIS — GENERAL DESCRIPTIONYD
Symptom Matrix Chart (Cont’d)
EC-62
TERMI-
NAL
NO.WIRE
COLORITEM CONDITIONDATA (DC Voltage and Pulse
Signal)
204 L Air conditioner relay[Engine is running]
Air conditioner switch is “OFF”BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Both air conditioner switch and blower fan
switch are “ON”
(Compressor is operating)Approximately 0.1V
214 W/B Glow relay Refer to “Glow Control System”, EC-188.
218 B Sensors’ ground[Engine is running]
Warm-up condition
Idle speedApproximately 0V
219 LG/R Cooling fan relay (Low)[Engine is running]
Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Cooling fan is operatingApproximately 0.1V
221 LG/B Cooling fan relay (High)[Engine is running]
Cooling fan is not operating
Cooling fan is operating at low speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Cooling fan is operating at high speedApproximately 0.1V
223 WMass air flow sensor
power supply[Ignition switch “ON”]Approximately 5V
224 R Mass air flow sensor[Engine is running]
Warm-up condition
Idle speed1.5 - 2.0V
313 L/WElectronic control fuel
injection pump[Engine is running]
Warm-up condition
Idle speedApproximately 0.1V
314 L/RElectronic control fuel
injection pump[Engine is running]
Warm-up condition
Idle speedApproximately 0.4V
316 PUElectronic control fuel
injection pump[Engine is running]
Warm-up condition
Idle speedApproximately 2.5V
317 PElectronic control fuel
injection pump[Engine is running]
Warm-up condition
Idle speedApproximately 2.5V
325 G ECM relay (Self-shutoff)[Ignition switch “ON”]
[Ignition switch “OFF”]
For a few seconds after turning ignition switch
“OFF”Approximately 0.25V
[Ignition switch “OFF”]
A few seconds passed after turning ignition
switch “OFF”BATTERY VOLTAGE
(11 - 14V)
331 ORCrankshaft position sen-
sor (TDC) ground[Engine is running]
Warm-up condition
Idle speedApproximately 0V
334 B/REngine coolant tempera-
ture sensor ground[Ignition switch “ON”]Approximately 0V
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TROUBLE DIAGNOSIS — GENERAL DESCRIPTIONYD
ECM Terminals and Reference Value (Cont’d)
EC-67
Main Power Supply and Ground Circuit
ECM TERMINALS AND REFERENCE VALUENJEC0639Remarks: Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM’s transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA(DC Voltage)
104
105
106B
B
BECM ground[Engine is running]
Idle speedApproximately 0V
107
108
109R
R
RPower supply for ECM[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
325 G ECM relay (Self-shutoff)[Ignition switch “ON”]
[Ignition switch “OFF”]
For a few seconds after turning ignition switch
“OFF”Approximatley 0.25V
[Ignition switch “OFF”]
A few seconds passed after turning ignition switch
“OFF”BATTERY VOLTAGE
(11 - 14V)
507 W/R Ignition switch[Ignition switch “OFF”]0V
[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
TROUBLE DIAGNOSIS FOR POWER SUPPLYYD
Main Power Supply and Ground Circuit
EC-72