![NISSAN ALMERA N16 2003  Electronic Repair Manual EC-24
[QG (WITH EURO-OBD)]
ENGINE CONTROL SYSTEM
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by  input  signals  (for  engine  speed  and  i NISSAN ALMERA N16 2003  Electronic Repair Manual EC-24
[QG (WITH EURO-OBD)]
ENGINE CONTROL SYSTEM
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by  input  signals  (for  engine  speed  and  i](/manual-img/5/57350/w960_57350-353.png)
EC-24
[QG (WITH EURO-OBD)]
ENGINE CONTROL SYSTEM
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by  input  signals  (for  engine  speed  and  intake  air)  from  the  crankshaft  position  sensor  (POS),  the  camshaft
position sensor (PHASE) and the mass air flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.
●During warm-up
●When starting the engine
●During acceleration
●Hot-engine operation
●When selector lever is changed from “N” to “D” (A/T models)
●High-load, high-speed operation
●During deceleration
●During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control.
The  three  way  catalyst  (manifold)  can  then  better  reduce  CO,  HC and NOx emissions. This system uses
heated  oxygen  sensor  1  in  the  exhaust  manifold  to  monitor  if  the  engine  operation  is  rich  or  lean.  The  ECM
adjusts  the  injection  pulse  width  according  to  the  sensor  voltage  signal.  For  more  information  about  heated
oxygen sensor 1, refer to EC-155
 . This maintains the mixture ratio within the range of stoichiometric (ideal air-
fuel mixture).
This stage is referred to as the closed loop control condition.
Heated  oxygen  sensor  2  is  located  downstream  of  the  three  way  catalyst  (manifold).  Even  if  the  switching
characteristics  of  heated  oxygen  sensor  1  shift,  the  air-fuel  ratio  is  controlled  to  stoichiometric  by  the  signal
from heated oxygen sensor 2.
Open Loop Control
The  open  loop  system  condition  refers  to  when  the  ECM  detects  any  of  the  following  conditions.  Feedback
control stops in order to maintain stabilized fuel combustion.
●Deceleration and acceleration
●High-load, high-speed operation
●Malfunction of heated oxygen sensor 1 or its circuit
●Insufficient activation of heated oxygen sensor 1 at low engine coolant temperature
●High engine coolant temperature
●During warm-up
●After shifting from “N” to “D” (A/T models)
●When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The  mixture  ratio  feedback  control  system  monitors  the  mixture ratio  signal  transmitted  from  heated  oxygen
sensor 1. This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to
the theoretical mixture ratio as possible. However, the basic mixture ratio is not necessarily controlled as orig-
PBIB0121E 
![NISSAN ALMERA N16 2003  Electronic Repair Manual ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-53
[QG (WITH EURO-OBD)]
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●The MI will  go off  after  the vehicle is driven 3  times with no malfunction.  The drive  is counted  only wh NISSAN ALMERA N16 2003  Electronic Repair Manual ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-53
[QG (WITH EURO-OBD)]
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●The MI will  go off  after  the vehicle is driven 3  times with no malfunction.  The drive  is counted  only wh](/manual-img/5/57350/w960_57350-382.png)
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-53
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●The MI will  go off  after  the vehicle is driven 3  times with no malfunction.  The drive  is counted  only when
the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs while counting,
the counter will reset.
●The DTC and the freeze frame  data  will be  stored  until  the vehicle is driven 40 times (driving pattern A)
without the same malfunction recurring (except for Misfire and Fuel  Injection  System).  For  Misfire  and
Fuel Injection System, the DTC and freeze frame data will be stored  until  the  vehicle  is  driven  80  times
(driving  pattern  C)  without  the  same  malfunction  recurring.  The  “TIME”  in  “SELF-DIAGNOSTIC
RESULTS” mode of CONSULT-II will count the number of times the vehicle is driven.
●The 1st trip DTC is not displayed when the self-diagnosis results in “OK” for the 2nd trip.
SUMMARY CHART
For details about patterns “B” and “C” under “Fuel Injection System” and “Misfire”, see EC-55 .
For details about patterns “A” and “B” under “Other”, see EC-57
 .
*1: Clear timing is at the moment OK is detected.
*2: Clear timing is when the same malfunction is detected in the 2nd trip. Items Fuel Injection System Misfire Other
MI (goes off) 3 (pattern B) 3 (pattern B) 3 (pattern B)
DTC, Freeze Frame Data (no 
display)80 (pattern C) 80 (pattern C) 40 (pattern A)
1st Trip DTC (clear) 1 (pattern C), *1 1 (pattern C), *1 1 (pattern B)
1st Trip Freeze Frame Data 
(clear)*1, *2 *1, *2 1 (pattern B) 
![NISSAN ALMERA N16 2003  Electronic Repair Manual TROUBLE DIAGNOSIS
EC-97
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Operation
1. “AUTO TRIG”
●While trying  to detect the  DTC/1st trip DTC by performing the “DTC Confirmation Procedure”, NISSAN ALMERA N16 2003  Electronic Repair Manual TROUBLE DIAGNOSIS
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Operation
1. “AUTO TRIG”
●While trying  to detect the  DTC/1st trip DTC by performing the “DTC Confirmation Procedure”,](/manual-img/5/57350/w960_57350-426.png)
TROUBLE DIAGNOSIS
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Operation
1. “AUTO TRIG”
●While trying  to detect the  DTC/1st trip DTC by performing the “DTC Confirmation 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, especially in case the incident is intermittent.
When  you  are  inspecting  the  circuit by gently  shaking  (or twisting)  the  suspicious  connectors, compo-
nents and harness in the “DTC Confirmation Procedure”, the moment a malfunction is found the DTC/
1st trip DTC will be displayed. (Refer to “Incident Simulation Tests” in GI-23.)
2. “MANU TRIG”
●If the malfunction is displayed as soon as “DATA MONITOR” is selected, reset CONSULT-II to “MANU
TRIG”. By selecting “MANU TRIG” you can monitor and store the data. The data can be utilized for fur-
ther diagnosis, such as a comparison with the value for the normal operating condition.
Generic Scan Tool (GST) FunctionEBS00K3V
DESCRIPTION
Generic  Scan  Tool  (OBDII  scan  tool)  complying  with  ISO  15031-4
has 8 different functions explained below.
ISO9141 is used as the protocol.
The name “GST” or “Generic Scan Tool” is used in this service man-
ual.
PBIB0197E
SEF139P 
![NISSAN ALMERA N16 2003  Electronic Repair Manual EC-98
[QG (WITH EURO-OBD)]
TROUBLE DIAGNOSIS
FUNCTION
GST INSPECTION PROCEDURE
1. Turn ignition switch OFF.
2. Connect “GST” to data link connector, which is located under the
driver side dash pan NISSAN ALMERA N16 2003  Electronic Repair Manual EC-98
[QG (WITH EURO-OBD)]
TROUBLE DIAGNOSIS
FUNCTION
GST INSPECTION PROCEDURE
1. Turn ignition switch OFF.
2. Connect “GST” to data link connector, which is located under the
driver side dash pan](/manual-img/5/57350/w960_57350-427.png)
EC-98
[QG (WITH EURO-OBD)]
TROUBLE DIAGNOSIS
FUNCTION
GST INSPECTION PROCEDURE
1. Turn ignition switch OFF.
2. Connect “GST” to data link connector, which is located under the
driver side dash panel near the fuse box cover.
3. Turn ignition switch ON.
4. Enter  the  program  according  to  instruction  on  the  screen  or  in
the operation manual.
(*:  Regarding  GST  screens  in  this  section,  sample  screens  are
shown.)
Diagnostic test mode Function
MODE 1 READINESS TESTSThis mode gains access to current emission-related data values, including analog inputs 
and outputs, digital inputs and outputs, and system status information.
MODE 2 (FREEZE DATA)This mode gains access to emission-related data value which were stored by ECM during 
the freeze frame. For details, refer to EC-40, "
FREEZE FRAME DATA AND 1ST TRIP 
FREEZE FRAME DATA" .
MODE 3 DTCsThis mode gains access to emission-related power train trouble codes which were stored 
by ECM.
MODE 4 CLEAR DIAG INFOThis mode can clear all emission-related diagnostic information. This includes:
●Clear number of diagnostic trouble codes (MODE 1)
●Clear diagnostic trouble codes (MODE 3)
●Clear trouble code for freeze frame data (MODE 1)
●Clear freeze frame data (MODE 2)
●Reset status of system monitoring test (MODE 1)
●Clear on board monitoring test results (MODE 6 and 7)
MODE 6 (ON BOARD TESTS)This mode accesses the results of on board diagnostic monitoring tests of specific com-
ponents/systems that are not continuously monitored.
MODE 7 (ON BOARD TESTS)This mode enables the off board test drive to obtain test results for emission-related pow-
ertrain components/systems that are continuously monitored during normal driving condi-
tions.
MODE 8 — This mode is not applicable on this vehicle.
MODE 9 (CALIBRATION ID)This mode enables the off-board test device to request specific vehicle information such 
as Vehicle Identification Number (VIN) and Calibration IDs.
MBIB0251E
SEF398S 
![NISSAN ALMERA N16 2003  Electronic Repair Manual EC-418
[QG (WITHOUT EURO-OBD)]
ENGINE CONTROL SYSTEM
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and inta NISSAN ALMERA N16 2003  Electronic Repair Manual EC-418
[QG (WITHOUT EURO-OBD)]
ENGINE CONTROL SYSTEM
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and inta](/manual-img/5/57350/w960_57350-747.png)
EC-418
[QG (WITHOUT EURO-OBD)]
ENGINE CONTROL SYSTEM
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from the crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the mass air flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.
●During warm-up
●When starting the engine
●During acceleration
●Hot-engine operation
●When selector lever is changed from “N” to “D” (A/T models)
●High-load, high-speed operation
●During deceleration
●During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control.
The  three  way  catalyst  (manifold)  can  then  better  reduce  CO,  HC and NOx emissions. This system uses
heated  oxygen  sensor  1  in  the  exhaust  manifold  to  monitor  if  the  engine  operation  is  rich  or  lean.  The  ECM
adjusts  the  injection  pulse  width  according  to  the  sensor  voltage  signal.  For  more  information  about  heated
oxygen sensor 1, refer to EC-506
 . This maintains the mixture ratio within the range of stoichiometric (ideal air-
fuel mixture).
This stage is referred to as the closed loop control condition.
Heated  oxygen  sensor  2  is  located  downstream  of  the  three  way  catalyst  (manifold).  Even  if  the  switching
characteristics  of  heated  oxygen  sensor  1  shift,  the  air-fuel  ratio  is  controlled  to  stoichiometric  by  the  signal
from heated oxygen sensor 2.
Open Loop Control
The  open  loop  system  condition  refers  to  when  the  ECM  detects  any  of  the  following  conditions.  Feedback
control stops in order to maintain stabilized fuel combustion.
●Deceleration and acceleration
●High-load, high-speed operation
●Malfunction of heated oxygen sensor 1 or its circuit
●Insufficient activation of heated oxygen sensor 1 at low engine coolant temperature
●High engine coolant temperature
●During warm-up
●After shifting from “N” to “D” (A/T models)
●When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The  mixture  ratio  feedback  control  system  monitors  the  mixture ratio  signal  transmitted  from  heated  oxygen
sensor 1. This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to
the theoretical mixture ratio as possible. However, the basic mixture ratio is not necessarily controlled as orig-
PBIB0121E 
![NISSAN ALMERA N16 2003  Electronic Repair Manual TROUBLE DIAGNOSIS
EC-475
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Operation
1. “AUTO TRIG”
●While trying  to detect the  DTC/1st trip DTC by performing the “DTC Confirmation Procedure NISSAN ALMERA N16 2003  Electronic Repair Manual TROUBLE DIAGNOSIS
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Operation
1. “AUTO TRIG”
●While trying  to detect the  DTC/1st trip DTC by performing the “DTC Confirmation Procedure](/manual-img/5/57350/w960_57350-804.png)
TROUBLE DIAGNOSIS
EC-475
[QG (WITHOUT EURO-OBD)]
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Operation
1. “AUTO TRIG”
●While trying  to detect the  DTC/1st trip DTC by performing the “DTC Confirmation 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, especially in case the incident is intermittent.
When  you  are  inspecting  the  circuit by gently  shaking  (or twisting)  the  suspicious  connectors, compo-
nents and harness in the “DTC Confirmation Procedure”, the moment a malfunction is found the DTC/
1st trip DTC will be displayed. (Refer to “Incident Simulation Tests” in GI-23.)
2. “MANU TRIG”
●If the malfunction is displayed as soon as “DATA MONITOR” is selected, reset CONSULT-II to “MANU
TRIG”. By selecting “MANU TRIG” you can monitor and store the data. The data can be utilized for fur-
ther diagnosis, such as a comparison with the value for the normal operating condition.
CONSULT-II Reference Value in Data Monitor ModeEBS00KF1
Remarks:
● Specification data are reference values.
● Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
i.e.  Adjust ignition  timing  with  a  timing  light before  monitoring IGN  TIMING,  because  the  monitor  may  show the  specification  data in
spite  of  the  ignition  timing  not  being  adjusted  to  the  specification  data.  This  IGN  TIMING  monitors  the  data  calculated  by  the ECM
according to the signals input from the camshaft position sensor and other ignition timing related sensors.
PBIB0197E
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED
●Tachometer: Connect
●Run engine and compare tachometer indication with the CONSULT-II 
value.Almost the same speed as the 
CONSULT-II value. 

Fuel Injection Control System
DESCRIPTIONNJEC0612System DescriptionNJEC0612S01Three types of fuel injection control are provided to accommodate engine operating conditions; normal control,
idle control and start control. The ECM determines the appropriate fuel injection control. Under each control,
the amount of fuel injected is compensated to improve engine performance.
Pulse signals are exchanged between ECM and electronic control fuel injection pump (control unit is built-in).
The fuel injection pump control unit performs duty control on the spill valve (built into the fuel injection pump)
according to the input signals to compensate the amount of fuel injected tothe preset value.
Start ControlNJEC0612S02Input/Output Signal ChartNJEC0612S0201
Sensor Input Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection
control (start
control)Electronic control fuel
injection pump Crankshaft position sensor (TDC) Engine speed
Ignition switch Start signal
SEF648S
When the ECM receives a start signal from the ignition switch, the ECM adapts the fuel injection system for
the start control. The amount of fuel injected at engine starting is a preset program value in the ECM. The
program is determined by the engine speed and engine coolant temperature.
For better startability under cool engine conditions, the lower the coolant temperature becomes, the greater
the amount of fuel injected. The ECM ends the start control when the engine speed reaches the specific value,
and shifts the control to the normal or idle control.
Idle ControlNJEC0612S03Input/Output Signal ChartNJEC0612S0301
Sensor Input Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection
control (Idle con-
trol)Electronic control fuel
injection pump Crankshaft position sensor (TDC) Engine speed
Battery Battery voltage
Accelerator position switch Idle position
Vehicle speed sensor Vehicle speed
Air conditioner switch Air conditioner signal
When the ECM determines that the engine speed is at idle, the fuel injectionsystem is adapted for the idle
control. The ECM regulates the amount of fuel injected corresponding to changes in load applied to the engine
to keep engine speed constant. The ECM also provides the system with a fast idle control in response to the
engine coolant temperature signal.
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ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTIONYD
Fuel Injection Control System
EC-17 

the “DTC Confirmation Procedure”, the moment a malfunction
is found the DTC will be displayed. Refer to GI-23, “Incident
Simulation Tests”.
2) “MANU TRIG”
If the malfunction is displayed as soon as “DATA MONITOR”
is selected, reset CONSULT-II to “MANU TRIG”. By selecting
“MANU TRIG” you can monitor and store the data. The data
can be utilized for further diagnosis, such as a comparison with
the value for the normal operating condition.
SEF720X
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD
CONSULT-II (Cont’d)
EC-43