2003 NISSAN ALMERA N16 ecm

EC-26
[QG (WITH EURO-OBD)]
ENGINE CONTROL SYSTEM
SYSTEM DESCRIPTION
The ignition timing is controlled by the ECM to maintain the best air-
fuel ratio for every running condition of the engine. The ignition tim-
ing data is stored in the ECM. This data forms the map shown.
The ECM receives information such as the injection pulse width and
camshaft position sensor signal. Computing this information, ignition
signals are transmitted to the power transistor.
e.g., N: 1,800 rpm, Tp: 1.50 msec
A°BTDC
During the following conditions, the ignition timing is revised by the
ECM according to the other data stored in the ECM.
●At starting
●During warm-up
●At idle
●At low battery voltage
●During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Air Conditioning Cut ControlEBS00K37
INPUT/OUTPUT SIGNAL CHART
*1: These signals are sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
●When the accelerator pedal is fully depressed.
●When cranking the engine.
●At high engine speeds.
●When the engine coolant temperature becomes excessively high.
●When operating power steering during low engine speed or low vehicle speed.
●When engine speed is excessively low.
●When refrigerant pressure is excessively low or high.
SEF742M
Sensor Input Signal to ECM ECM Function Actuator
Air conditioner switch*
1Air conditioner “ON” signal
Air conditioner
cut controlAir conditioner relay Throttle position sensor Throttle valve opening angle
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
*2
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage
*2
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Vehicle speed signal
*1Vehicle speed

ENGINE CONTROL SYSTEM
EC-27
[QG (WITH EURO-OBD)]
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Fuel Cut Control (at No Load and High Engine Speed)EBS00K38
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
If the engine speed is above 3,950 rpm with no load (for example, in neutral and engine speed over 3,950
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 “Multiport Fuel Injection (MFI) System”, EC-23
.
CAN CommunicationEBS00K39
SYSTEM DESCRIPTION
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
CAN COMMUNICATION UNIT
×:ApplicableSensor Input Signal to ECM ECM Function Actuator
Park/neutral position (PNP) switch Neutral position
Fuel cut control Fuel injectors Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
Vehicle speed signal
*1Vehicle speed
Body type Sedan/ 5DH/B/ 3DH/B
Axle2WD
Engine QG18DE QG15DE/QG18DE
Transmission A/T M/T
Brake controlABS
CAN communication unit
ECM××
TCM×
Smart entrance control unit××
Data link connector××
Combination meter××
CAN communication type EC-28, "
Type 1"EC-29, "Ty p e 2"

EC-28
[QG (WITH EURO-OBD)]
ENGINE CONTROL SYSTEM
Ty p e 1
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
T: Transmit R: Receive
SEL825Y
Signals ECM TCMSmart entrance
control unitCombination meter
Engine speed signal T R
Brake switch signal R T
Rear window defogger signal R T
Heater fan switch signal R T
Air conditioner switch signal R T
MI signal T R
Current gear position signal T R
Engine coolant temperature signal T R
Fuel consumption signal T R
Vehicle speed signal R T
Seat belt reminder signalRT
Headlamp switch signalTR
Flashing indicator signalTR
Engine cooling fan speed signal T R
Child lock indicator signalTR
Door switches state signalTR
A/C compressor signal T R
Accelerator pedal position signal T R
Output shaft revolution signal R T
OD OFF switch signal R T
OD OFF indicator signal T R
A/T self-diagnosis signal R T

ENGINE CONTROL SYSTEM
EC-29
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Ty p e 2
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
T: Transmit R: Receive
SEL826Y
Signals ECMSmart entrance control
unitCombination meter
Engine speed signal T R
Rear window defogger signal R T
Heater fan switch signal R T
Air conditioner switch signal R T
MI signal T R
Engine coolant temperature signal T R
Fuel consumption signal T R
Vehicle speed signal R T
Seat belt reminder signal R T
Headlamp switch signal T R
Flashing indicator signal T R
Engine cooling fan speed signal T R
Child lock indicator signal T R
Door switches state signal T R
A/C compressor signal T R

BASIC SERVICE PROCEDURE
EC-31
[QG (WITH EURO-OBD)]
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EC
2. Connect No. 1 ignition coil and No. 1 spark plug with suitable
high-tension wire as shown, and attach timing light clamp to this
wire.
3. Check ignition timing.
Accelerator Pedal Released Position LearningEBS00K3B
DESCRIPTION
“Accelerator Pedal Released Position Learning” is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch “ON” and wait at least 2 seconds.
3. Turn ignition switch “OFF” wait at least 10 seconds.
4. Turn ignition switch “ON” and wait at least 2 seconds.
5. Turn ignition switch “OFF” wait at least 10 seconds.
Throttle Valve Closed Position LearningEBS00K3C
DESCRIPTION
“Throttle Valve Closed Position Learning” is an operation to learn the fully closed position of the throttle valve
by monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch “ON”.
3. Turn ignition switch “OFF” wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningEBS00K3D
DESCRIPTION
“Idle Air Volume Learning” is an operation to learn the idle air volume that keeps each engine within the spe-
cific range. It must be performed under any of the following conditions:
●Each time electric throttle control actuator or ECM is replaced.
●Idle speed or ignition timing is out of specification.
MBIB0049E
SEF166Y

EC-36
[QG (WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
ON BOARD DIAGNOSTIC (OBD) SYSTEM
PFP:00028
IntroductionEBS00K3F
The ECM has an on board diagnostic system, which detects malfunctions related to engine sensors or actua-
tors. The ECM also records various emission-related diagnostic information including:
The above information can be checked using procedures listed in the table below.
×: Applicable —: Not applicable
*1: 1st trip DTCs for self-diagnoses concerning SRT items cannot be shown on the GST display.
*2: When DTC and 1st trip DTC simultaneously appear on the display, they cannot be clearly distinguished from each other.
The malfunction indicator (MI) on the instrument panel lights up when the same malfunction is detected in two
consecutive trips (Two trip detection logic), or when the ECM enters fail-safe mode. (Refer to EC-63
.)
Two Trip Detection LogicEBS00K3G
When a malfunction is detected for the first time, 1st trip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MI will not light up at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MI lights up. The MI lights up at the same time when the DTC is stored. <2nd trip>
The “trip” in the “Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed during
vehicle operation. Specific on board diagnostic items will cause the ECM to light up or blink the MI, and store
DTC and Freeze Frame data, even in the 1st trip, as shown below.
×: Applicable —: Not applicable
When there is an open circuit on MI circuit, the ECM cannot warn the driver by lighting MI up when there is
malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as
NG for 5 trips, ECM warns the driver that engine control system malfunctions and MI circuit is open by means
of operating fail-safe function.
Emission-related diagnostic information ISO Standard
Diagnostic Trouble Code (DTC) Mode 3 of ISO 15031-5
Freeze Frame data Mode 2 of ISO 15031-5
System Readiness Test (SRT) code Mode 1 of ISO 15031-5
1st Trip Diagnostic Trouble Code (1st Trip DTC) Mode 7 of ISO 15031-5
1st Trip Freeze Frame data
Test values and Test limits Mode 6 of ISO 15031-5
Calibration ID Mode 9 of ISO 15031-5
DTC 1st trip DTCFreeze Frame
data1st trip Freeze
Frame dataSRT code Test value
CONSULT-II×× × × ×—
GST×
×*
1×—××
ECM×
×*
2————
ItemsMI DTC 1st trip DTC
1st trip 2nd trip
1st trip
displaying2nd trip
displaying1st trip
displaying2nd trip
display-
ing BlinkingLighting
upBlinkingLighting
up
Misfire (Possible three way cata-
lyst damage) — DTC: P0300 -
P0304 is being detected×———— —×—
Misfire (Possible three way cata-
lyst damage) — DTC: P0300 -
P0304 is being detected——×——×——
One trip detection diagnoses
(Refer to EC-10
.)—×——×—×—
Except above — — —×—××—

ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-37
[QG (WITH EURO-OBD)]
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EC
The fail-safe function also operates when above diagnoses except MI circuit and demands the driver to repair
the malfunction.
Emission-related Diagnostic InformationEBS00K3H
EMISSION-RELATED DIAGNOSTIC INFORMATION ITEMS
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
Items
(CONSULT-II screen terms)DTC*
1
SRT codeTest Value/
Test Limit
(GST only)1st trip DTC Reference page
CONSULT-II
GST*
2ECM
CAN COMM CIRCUIT U1000
1000*
3———EC-116
CAN COMM CIRCUIT U1001
1001*3——×EC-116
NO DTC IS DETECTED.
FURTHER TESTING
MAY BE REQUIRED.P0000 0000————
INT/V TIM CONT-B1 P0011 0011 — —×EC-119
HO2S1 HTR (B1) P0031 0031××
×*4EC-122
HO2S1 HTR (B1) P0032 0032××
×*4EC-122
HO2S2 HTR (B1) P0037 0037××
×*4EC-128
HO2S2 HTR (B1) P0038 0038××
×*4EC-128
MAF SEN/CIRCUIT P0102 0102 — — —EC-134
MAF SEN/CIRCUIT P0103 0103 — — —EC-134
IAT SEN/CIRCUIT P0112 0112 — —×EC-140
IAT SEN/CIRCUIT P0113 0113 — —×EC-140
ECT SEN/CIRCUIT P0117 0117 — — —EC-144
ECT SEN/CIRCUIT P0118 0118 — — —EC-144
HO2S1 (B1) P0132 0132××
×*4EC-149
HO2S1 (B1) P0133 0133××
×*4EC-155
HO2S1 (B1) P0134 0134××
×*4EC-165
HO2S2 (B1) P0138 0138××
×*4EC-172
HO2S2 (B1) P0139 0139××
×*4EC-178
FUEL SYS-LEAN-B1 P0171 0171 — —×EC-186
FUEL SYS-RICH-B1 P0172 0172 — —×EC-193
TP SENSOR P0221 0221 — — —EC-199
TP SEN 1/CIRC P0222 0222 — — —EC-205
TP SEN 1/CIRC P0223 0223 — — —EC-205
APP SENSOR P0226 0226 — — —EC-211
APP SEN 1/CIRC P0227 0227 — — —EC-218
APP SEN 1/CIRC P0228 0228 — — —EC-218
MULTI CYL MISFIRE P0300 0300 — —×EC-225
CYL 1 MISFIRE P0301 0301 — —×EC-225
CYL 2 MISFIRE P0302 0302 — —×EC-225
CYL 3 MISFIRE P0303 0303 — —×EC-225
CYL 4 MISFIRE P0304 0304 — —×EC-225
KNOCK SEN/CIRC-B1 P0327 0327 — —×EC-230
KNOCK SEN/CIRC-B1 P0328 0328 — —×EC-230
CKP SEN/CIRCUIT P0335 0335 — —×EC-234

EC-38
[QG (WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
CMP SEN/CIRC-B1 P0340 0340 — —×EC-240
TW CATALYST SYS-B1 P0420 0420××
×*4EC-246
PURG VOLUME CONT/V P0444 0444 — —×EC-251
VEH SPEED SEN/CIRC P0500 0500 — —×EC-257
PW ST P SEN/CIRC P0550 0550 — —×EC-260
ECM P0605 0605 — —×EC-265
PNP SW/CIRC P0705 0705 — —×AT- 111
ATF TEMP SEN/CIRC P0710 0710 — —×AT- 11 7
VEH SPD SEN/CIRC AT*5P0720 0720 — —×AT- 1 2 3
ENGINE SPEED SIG P0725 0725 — —×AT- 1 2 9
A/T 1ST GR FNCTN P0731 0731 — —×AT- 1 3 3
A/T 2ND GR FNCTN P0732 0732 — —×AT- 1 3 9
A/T 3RD GR FNCTN P0733 0733 — —×AT- 1 4 5
A/T 4TH GR FNCTN P0734 0734 — —×AT- 1 5 1
TCC SOLENOID/CIRC P0740 0740 — —×AT- 1 5 9
L/PRESS SOL/CIRC P0745 0745 — —×AT- 1 6 4
SFT SOL A/CIRC P0750 0750 — — —AT- 1 7 1
SFT SOL B/CIRC P0755 0755 — — —AT- 1 7 6
ECM BACK UP/CIRC P1065 1065 — —×EC-268
INT/V TIM V/CIR-B1 P1111 1111 — —×EC-272
ETC ACTR P1121 1121 — —×EC-276
ETC FUNCTION/CIRC P1122 1122 — — —EC-278
ETC MOT PWR P1124 1124 — — —EC-285
ETC MOT PWR P1126 1126 — — —EC-285
ETC MOT P11281128———EC-291
HO2S1 (B1) P1143 1143××
×*4EC-296
HO2S1 (B1) P1144 1144××
×*4EC-302
HO2S2 (B1) P1146 1146××
×*4EC-308
HO2S2 (B1) P1147 1147××
×*4EC-316
ENG OVER TEMP P1217 1217 — — —EC-324
TP SEN 2/CIRC P1223 1223 — — —EC-335
TP SEN 2/CIRC P1224 1224 — — —EC-335
CTP LEARNING P1225 1225 — —×EC-341
CTP LEARNING P1226 1226 — —×EC-343
APP SEN 2/CIRC P1227 1227 — — —EC-345
APP SEN 2/CIRC P1228 1228 — — —EC-345
SENSOR POWER/CIRC P1229 1229 — — —EC-352
NATS MALFUNCTION P1610 - P1615 1610 - 1615 — —×EC-49
TPV SEN/CIRC A/T P1705 1705 — — —AT- 1 8 1
P-N POS SW/CIRCUIT P1706 1706 — —×EC-356
Items
(CONSULT-II screen terms)DTC*
1
SRT codeTest Value/
Test Limit
(GST only)1st trip DTC Reference page
CONSULT-II
GST*
2ECM