![NISSAN ALMERA 2001 Service Manual Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
IGN TIMING [BTDC]j+Indicates the ignition timing computed by
ECM according to the input signals.
CAL/LD VALUE [%]+ªCalculated loa NISSAN ALMERA 2001 Service Manual Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
IGN TIMING [BTDC]j+Indicates the ignition timing computed by
ECM according to the input signals.
CAL/LD VALUE [%]+ªCalculated loa](/manual-img/5/57348/w960_57348-812.png)
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
IGN TIMING [BTDC]j+Indicates the ignition timing computed by
ECM according to the input signals.
CAL/LD VALUE [%]+ªCalculated load valueº indicates the value
of the current airflow divided by peak air-
flow.
ABSOL TH.P/S [%]+ªAbsolute throttle position sensorº indicates
the throttle opening computed by ECM
according to the signal voltage of the
throttle position sensor.
MASS AIRFLOW
[gm/s]+Indicates the mass airflow computed by
ECM according to the signal voltage of the
mass air flow sensor.
IACV-AAC/V [step]j+Indicates the IACV-AAC valve control value
computed by ECM according to the input
signals.
PURG VOL C/V [%]+Indicates the EVAP canister purge volume
control solenoid valve computed by the
ECM according to the inpuct signals.
+The opening becomes larger as the value
increases.
EGR VOL CON/V
[step]*j+Indicates the EGR volume control valve
computed by the ECM according to the
input signals.
+The opening becomes larger as the value
increases.
SWRL CONT S/V
[ON/OFF]*+The control condition of the swirl control
valve control solenoid valve (determined by
ECM according to the input signals) is indi-
cated.
+ON ... Swirl control valve is closed.
OFF ... Swirl control valve is opened.
INT/V SOL-B1
[ON/OFF]+The control condition of the valve timing
solenoid valve (determined by ECM accord-
ing to the input signal) is indicated.
ON ... Intake valve timing control operating
OFF ... Intake valve timing control not oper-
ating
AIR COND RLY
[ON/OFF]j+Indicates the air conditioner relay control
condition determined by ECM according to
the input signals.
FUEL PUMP RLY
[ON/OFF]j+Indicates the fuel pump relay control condi-
tion determined by ECM according to the
input signals.
COOLING FAN
[ON/OFF]j+Indicates [ON/OFF] control condition of the
cooling fan determined by ECM according
to the input signals.
HO2S1 HTR (B1)
[ON/OFF]+Indicates [ON/OFF] condition of heated oxy-
gen sensor 1 heater (front) determined by
ECM according to the input signals.
HO2S2 HTR (B1)
[ON/OFF]+Indicates [ON/OFF] condition of heated oxy-
gen sensor 2 heater (rear) determined by
ECM according to the input signals.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
CONSULT-II (Cont'd)
EC-89

TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
IACV-AAC/V
OPENING+Engine: After warming up, idle
the engine.
+Change the IACV-AAC valve
opening steps using CONSULT-
II.Engine speed changes according
to the opening steps.+Harness and connector
+IACV-AAC valve
POWER BAL-
ANCE+Engine: After warming up, idle
the engine.
+Air conditioner switch ªOFFº
+Shift lever ªNº
+Cut off each injector signal one
at a time using CONSULT-II.Engine runs rough or dies.+Harness and connector
+Compression
+Injectors
+Power transistor
+Spark plugs
+Ignition coils
COOLING FAN+Ignition switch: ON
+Turn the cooling fan ªONº and
ªOFFº using CONSULT-II.Cooling fan moves and stops.+Harness and connector
+Cooling fan motor
ENG COOLANT
TEMP+Engine: Return to the original
trouble condition
+Change the engine coolant tem-
perature indication using CON-
SULT-II.If trouble symptom disappears, see
CHECK ITEM.+Harness and connector
+Engine coolant temperature sen-
sor
+Fuel injectors
FUEL PUMP
RELAY+Ignition switch: ON
(Engine stopped)
+Turn the fuel pump relay ªONº
and ªOFFº using CONSULT-II
and listen to operating sound.Fuel pump relay makes the operat-
ing sound.+Harness and connector
+Fuel pump relay
EGR VOL
CONT/V
(If so equipped)+Engine: After warming up, idle
the engine.
+Change the EGR volume control
valve opening step using CON-
SULT-II.Engine speed changes according
to the opening step.+Harness and connector
+EGR volume control valve
VALVE TIMING
SOL+Ignition switch: ON
+Turn intake valve timing control
solenoid valve ªONº and ªOFFº
using CONSULT-II and listen for
operating sound.Intake valve timing control solenoid
valve makes an operating sound.+Harness and connector
+Intake valve timing control sole-
noid valve
SWIRL CONT
S O L VA LV E
(If so equipped)+Ignition switch: ON
+Turn solenoid valve ªONº and
ªOFFº with CONSULT-II and lis-
ten for operating sound.Solenoid valve makes an operating
sound.+Harness and connector
+Solenoid valve
PURG VOL
CONT/V+Engine: After warming up, idle
the engine.
+Change the EVAP canister
purge volume control solenoid
valve opening percent using
CONSULT-II.Engine speed changes according
to the opening percent.+Harness and connector
+EVAP canister purge volume
control solenoid valve
DTC AND SRT CONFIRMATION MODENJEC0034S08This mode is not available for models without Euro-OBD system.
SRT STATUS ModeNJEC0034S0801For details, refer to ªSYSTEM READINESS TEST (SRT) CODEº,
EC-62.
SRT Work Support ModeNJEC0034S0803This mode enables a technician to drive a vehicle to set the SRT
while monitoring the SRT status.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
CONSULT-II (Cont'd)
EC-91

Fail-safe Chart=NJEC0040The ECM enters fail-safe mode if any of the following malfunctions is detected due to the open or short cir-
cuit. When the ECM enters the fail-safe mode, the MI illuminates.
DTC No.
Detected items Engine operating condition in fail-safe mode CON-
SULT-II
GSTECM*1
P0100 0100 Mass air flow sensor
circuitEngine speed will not rise more than 2,400 rpm due to the fuel cut.
P0115 0115 Engine coolant tempera-
ture sensor circuitEngine coolant temperature will be determined by ECM based on the time
after turning ignition switch ªONº or ªSTARTº.
CONSULT-II displays the engine coolant temperature decided by ECM.
The radiator fan operates.
ConditionEngine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned
ON or Start40ÉC (104ÉF)
More than approx. 4 minutes
after ignition ON or Start80ÉC (176ÉF)
Except as shown above40 - 80ÉC (104 - 176ÉF)
(Depends on the time)
P0120 0120 Throttle position sensor
circuitThrottle position will be determined based on the injected fuel amount and
the engine speed. Therefore, acceleration will be poor.
Condition Driving condition
When engine is idling Normal
When accelerating Poor acceleration
Unable to
access
ECMUnable to
access
Diagnostic
Test Mode
IIECMECM fail-safe activating condition
The computing function of the ECM was judged to be malfunctioning.
When the fail-safe system activates (i.e., if the ECM detects a malfunction
condition in the CPU of ECM), the MI on the instrument panel lights to warn
the driver.
However it is not possible to access ECM and DTC cannot be confirmed.
Engine control with fail-safe
When ECM fail-safe is operating, fuel injection, ignition timing, fuel pump
operation and IACV-AAC valve operation are controlled under certain limita-
tions.
ECM fail-safe operation
Engine speedEngine speed will not rise more than
3,000 rpm
Fuel injectionSimultaneous multiport fuel injection sys-
tem
Ignition timing Ignition timing is fixed at the preset value
Fuel pumpFuel pump relay is ªONº when engine is
running and ªOFFº when engine stalls
IACV-AAC valve Full open
Cooling fansCooling fan relay ªONº (High speed condi-
tion) when engine is running, and ªOFFº
when engine stalls.
Replace ECM, if ECM fail-safe condition is confirmed.
*: In Diagnostic Test Mode II (Self-diagnostic results) (If so equipped)
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
Fail-safe Chart
EC-154
![NISSAN ALMERA 2001 Service Manual TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
13 LG/R Cooling fan relay[Engine is running]
+Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Cooling fan is operat NISSAN ALMERA 2001 Service Manual TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
13 LG/R Cooling fan relay[Engine is running]
+Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Cooling fan is operat](/manual-img/5/57348/w960_57348-890.png)
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
13 LG/R Cooling fan relay[Engine is running]
+Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Cooling fan is operatingApproximately 0V
14 GY/LEVAP canister purge
volume control valve
(ON/OFF duty)[Engine is running]
+Warm-up condition
+Accelerator pedal depressed5 - 12V
SEF975W
19 BR/W A/T signal No. 5[Engine is running]
+Idle speedApproximately 8V
21 B/P Fuel pump relay[Ignition switch ªONº]
+For 1 second after turning ignition switch
ªONº
[Engine is running]0-1V
[Ignition switch ªONº]
+More than 1 second after turning ignition
switch ªONºBATTERY VOLTAGE
(11 - 14V)
22 OR/L Malfunction indicator[Ignition switch ªONº]0-1V
[Engine is running]
+Idle speedBATTERY VOLTAGE
(11 - 14V)
23 L Air conditioner relay[Engine is running]
+Both A/C switch and blower switch are ªONºApproximately 0V
[Engine is running]
+A/C switch is ªOFFºBATTERY VOLTAGE
(11 - 14V)
31 W/G ECM relay (Self shut-off)[Ignition switch ªOFFº]
+For 9 seconds after turning ignition switch
ªOFFº0-1V
[Ignition switch ªOFFº]
+9 seconds passed after turning ignition switch
ªOFFºBATTERY VOLTAGE
(11 - 14V)
32 L/OR Tachometer[Engine is running]
+Warm-up condition
+Idle speed7-8V
SEF928X
[Engine is running]
+Engine speed is 2,000 rpm7-8V
SEF929X
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
ECM Terminals and Reference Value (Cont'd)
EC-167

ECM TERMINALS AND REFERENCE VALUENJEC0048Specification 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)
31 W/G ECM relay (Self shut-off)[Engine is running]
[Ignition switch ªOFFº]
+For 9 seconds after turning ignition switch ªOFFº0-1V
[Ignition switch ªOFFº]
+9 seconds passed after turning ignition switch
ªOFFºBATTERY VOLTAGE
(11 - 14V)
43 B/R Ignition switch[Ignition switch ªOFFº]0V
[Ignition switch ªONº]BATTERY VOLTAGE
(11 - 14V)
48 B ECM ground[Engine is running]
+Idle speedEngine ground
57 B ECM ground[Engine is running]
+Idle speedEngine ground
67 W/LPower supply for ECM
(Back-up)[Ignition switch ªOFFº]BATTERY VOLTAGE
(11 - 14V)
106
108B/Y
B/YECM ground[Engine is running]
+Idle speedEngine ground
11 0
11 2W
WPower supply for ECM[Ignition switch ªONº]BATTERY VOLTAGE
(11 - 14V)
DIAGNOSTIC PROCEDURENJEC0565
1 INSPECTION START
Start engine.
Is engine running?
YesorNo
Ye s©GO TO 9.
No©GO TO 2.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-181

5 CHECK POWER SUPPLY-II
1. Disconnect ECM relay. (For ECM relay location, refer to ªEngine Control Compartment Parts Locationº.)
2. Check voltage between ECM relay terminals 1, 6 and ground with CONSULT-II or tester.
SEF101Y
OK or NG
OK©GO TO 7.
NG©GO TO 6.
6 DETECT MALFUNCTIONING PART
Check the following.
+15A fuse and 10A fuse
+Harness connectors E75, F36 (If so equipped)
+Harness for open or short between ECM relay and battery
©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 31 and ECM relay terminal 2.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©Go to ªIGNITION SIGNALº, EC-547.
NG©GO TO 8.
8 DETECT MALFUNCTIONING PART
Check the harness for open or short between ECM relay and ECM.
©Repair open circuit or short to ground or short to power in harness or connectors.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-183

12 CHECK ECM POWER SUPPLY CIRCUIT-IV
1. Disconnect ECM relay. (For ECM relay location, refer to ªEngine Control Compartment Parts Locationº.)
2. Check voltage between ECM relay terminal 3 or 5 (only ECM relay in relay box) and ground with CONSULT-II or tester.
YEC048A
OK or NG
OK©GO TO 14.
NG©GO TO 13.
13 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E75, F36 (If so equipped)
+Harness for open or short between ECM relay and 10A fuse
©Repair open circuit or short to ground or short to power in harness or connectors.
14 CHECK HARNESS CONTINUITY BETWEEN ECM RELAY AND ECM FOR OPEN AND SHORT
1. Check harness continuity between ECM terminals 110, 112 and ECM relay terminal 5 or 3 (only ECM relay in relay
box).
Refer to WIRING DIAGRAM.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 16.
NG©GO TO 15.
15 DETECT MALFUNCTIONING PART
Check the following.
+Joint connector-4 (If so equipped)
+Joint connector-6 (If so equipped)
+Harness connector E75, F36 (If so equipped)
+Harness for open or short between ECM and ECM relay
©Repair open circuit or short to ground or short to power in harness or connectors.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-185

16 CHECK ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check continuity between relay terminals 3 and 5, 6 and 7.
SEF296X
OK or NG
OK©GO TO 17.
NG©Replace ECM relay.
17 CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminals 48, 57, 106, 108 and engine ground.
Refer to WIRING DIAGRAM.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 18.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
18 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
©INSPECTION END
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-186