2001 NISSAN ALMERA N16 Mass air flow sensor

DTC Inspection Priority ChartNJEC0039If some DTCs are displayed at the same time, perform inspections one by one based on the following prior-
ity chart.
Priority Detected items (DTC)
1+P0100 Mass air flow sensor
+P0110 Intake air temperature sensor
+P0115 Engine coolant temperature sensor
+P0120 Throttle position sensor
+P0325 Knock sensor
+P0340 Camshaft position sensor (PHASE) circuit
+P0403 EGR volume control valve*1
+P0500 Vehicle speed sensor
+P0605 ECM
+P0335 Crankshaft position sensor (POS)
+P1605 A/T diagnostic communication line
+P1706 Park/Neutral position switch
2+P0130 - P0134 Heated oxygen sensor 1 (front)
+P0135 Heated oxygen sensor 1 heater (front)
+P0137 - P0140 Heated oxygen sensor 2 (rear)
+P0141 Heated oxygen sensor 2 heater (rear)
+P0443 EVAP canister purge volume control solenoid valve
+P0510 Closed throttle position switch*1
+P0705 - P0725, P0740 - P1760 A/T related sensors, solenoid valves and switches
+P1217 Overheat (Cooling system)
+P1401 EGR temperature sensor*1
3+P0171, P0172 Fuel injection system function
+P0300 - P0304 Misfire
+P0400, P1402 EGR function*1
+P0420 Three way catalyst function
+P0505 IACV-AAC valve
+P0731 - P0734, P0744 A/T function
+P 1111Intake valve timing control
*1: If so equipped
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
DTC Inspection Priority Chart
EC-122

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-123

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-272
Camshaft position sensor
(PHASE) circuit3 2 3 EC-278
Mass air flow sensor circuit11222 22 2EC-152
Heated oxygen sensor 1 (front)
circuit1232 22 2EC-176,
183
Engine coolant temperature sen-
sor circuit112323223 2EC-163,
165
Throttle position sensor circuit 1 222222 2EC-168
Incorrect throttle position sensor
adjustment31 11111 1EC-98
Vehicle speed sensor circuit 2 3 3 3 EC-309
Knock sensor circuit 2 3 EC-268
ECM 22333333333EC-327,
123
Start signal circuit 2EC-461
PNP switch circuit 3 3 3 3 3 EC-364
Power steering oil pressure switch
circuit2 3 3 EC-471
Electrical load signal circuit 3 3 EC-480
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
Symptom Matrix Chart (Cont'd)
EC-125

SYSTEM Ð ENGINE MECHANICAL & OTHERNJEC0041S03
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
Fuel Fuel tank
5
5FE section
Fuel piping 5 5 5 5 5 5
Ð Vapor lock
Valve deposit
5 555 55 5
Poor fuel (Heavy weight
gasoline, Low octane)
Air Air duct
55555 5 Air cleaner
Air leakage from air duct
(Mass air flow sensor Ð
throttle body)
5555
Throttle body, Throttle wireFE section
Air leakage from intake
manifold/Collector/GasketÐ
Cranking Battery
111111 11
EL section Alternator circuit
Starter circuit 3
Flywheel/drive plate 6EM section
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
Symptom Matrix Chart (Cont'd)
EC-126

CONSULT-II Reference Value in Data Monitor
Mode
NJEC0042Remarks:
+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. Specification data might be displayed even when igni-
tion timing is not adjusted to specification. This IGN TIMING monitors the data calculated by the ECM according to the input signals
from the crankshaft position sensor and other ignition timing related sensors.)
+If the real-time diagnosis results are NG, and the on board diagnostic system results are OK, when diagnosing the mass air flow sensor,
first check to see if the fuel pump control circuit is normal.
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.
MAS A/F SE-B1+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 1.0 - 1.7V
2,500 rpm 1.5 - 2.1V
B/FUEL SCHDL+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 1.5 - 3.0 msec
2,000 rpm 1.2 - 3.0 msec
A/F ALPHA-B1+Engine: After warming upMaintaining engine speed at 2,000
rpm75 - 125%
COOLAN TEMP/S+Engine: After warming up More than 70ÉC (158ÉF)
HO2S1 (B1)
+Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V¨0.6 - 1.0V
HO2S1 MNTR (B1)LEAN¨RICH
Changes more than 5 times
during 10 seconds.
HO2S2 (B1)
+Engine: After warming upRevving engine from idle to 3,000
rpm quickly0 - 0.3V¨0.6 - 1.0V
HO2S2 MNTR (B1)LEAN¨RICH
VHCL SPEED SE+Turn drive wheels and compare speedometer indication with the CON-
SULT-II valueAlmost the same speed as the
CONSULT-II value
BATTERY VOLT+Ignition switch: ON (Engine stopped) 11 - 14V
THRTL POS SEN+Engine: Idle Throttle valve fully closed 0.15 - 0.85V
+Ignition switch: ON
(Engine stopped)Throttle valve fully opened 3.5 - 4.7V
EGR TEMP SEN*+Engine: After warming up Less than 4.5V
START SIGNAL+Ignition switch: ON®START®ON OFF®ON®OFF
CLSD THL POS
CLSD THL/P SW*+Engine: Idle Throttle valve: Idle position ON
+Ignition switch: ON
(Engine stopped)Throttle valve: Slightly open OFF
AIR COND SIG+Engine: After warming up, idle
the engineA/C switch ªOFFº OFF
A/C switch ªONº
(Compressor operates)ON
P/N POSI SW+Ignition switch: ONShift lever ªPº or ªNº ON
Except above OFF
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
CONSULT-II Reference Value in Data Monitor Mode
EC-128

TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
61 G Mass air flow sensor[Engine is running]
+Warm-up condition
+Idle speed1.0 - 1.7V
[Engine is running]
+Warm-up condition
+Engine speed is 2,500 rpm1.5 - 2.1V
62 WHeated oxygen sensor 1
(front)[Engine is running]
+Warm-up condition
+Engine speed is 2,000 rpm0 - Approximately 0.7V
SEF008W
63 LHeated oxygen sensor 2
(rear)[Engine is running]
+After warming up to normal operating tem-
perature and engine speed is 3,000 rpm0 - Approximately 1.0V
64 Y/BIntake air temperature
sensor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with
intake air temperature
66
75R
RCamshaft position sen-
sor (PHASE)[Engine is running]
+Warm-up condition
+Idle speed2.0 - 3.0V
SEF977W
[Engine is running]
+Engine speed is 2,000 rpm2.0 - 3.0V
SEF978W
67 W/LPower supply for ECM
(Back-up)[Ignition switch ªOFFº]BATTERY VOLTAGE
(11 - 14V)
70 BR/WEngine coolant tempera-
ture sensor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with
engine coolant temperature
71 GYThrottle position sensor
signal output[Engine is running]
+Warm-up condition
+Accelerator pedal fully releasedApproximately 0.4V
[Ignition switch ªONº]
+Accelerator pedal fully depressedApproximately 4V
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
ECM Terminals and Reference Value (Cont'd)
EC-137

TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
72* P/B EGR temperature sensor[Engine is running]
+Warm-up condition
+Idle speedLess than 4.5V
[Engine is running]
+Warm-up condition
+EGR system is operating0 - 1.0V
73 BMass air flow sensor
ground[Engine is running]
+Warm-up condition
+Idle speedApproximately 0V
74 R/LRefrigerant pressure
sensor[Engine is running]
+Air conditioner switch is ªONº
(Compressor operates)1.0 - 4.0V
[Engine is running]
+Warm-up condition
+Idle speed
+Air conditioner switch is turned from ªONº to
ªOFFºVoltage is gradually decreasing.
81 W Knock sensor[Engine is running]
+Idle speed1.0 - 4.0V
85 RCrankshaft position sen-
sor (POS)[Engine is running]
+Warm-up condition
+Idle speed3.0 - 4.0V
SEF979W
[Engine is running]
+Engine speed is 2,000 rpm3.0 - 4.0V
SEF980W
86 PU/R Vehicle speed sensor[Engine is running]
+Lift up the vehicle
+Vehicle speed is 40 km/h (25 MPH)2.5-3V
SEF976W
91 PU A/T check signal[Engine is running]
+Idle speed0 - Approximately 5V
92 Y Throttle position sensor[Engine is running]
+Accelerator pedal released0.15 - 0.85V
[Ignition switch ªONº]
+Accelerator pedal fully depressed3.5 - 4.7V
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
ECM Terminals and Reference Value (Cont'd)
EC-138

DescriptionNJEC1265The 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 (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 ConditionNJEC1266+Vehicle driven distance: More than 5,000 km (3,017 miles)
+Barometric pressure: 98.3 - 104.3 kPa (0.983 - 1.043 bar, 1.003 - 1.064 kg/cm2, 14.25 - 15.12 psi)
+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 A/T or CVT models, after the engine is warmed up to normal operating temperature, drive vehicle until
ªFLUID TEMP SEº (A/T or CVT fluid temperature sensor signal) indicates less than 0.9V. For M/T models, drive
vehicle for 5 minutes after the engine is warmed up to normal operating temperature.
*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 ProcedureNJEC1267NOTE:
Perform ªDATA MONITOR (SPEC)º mode in maximum scale dis-
play.
1. Perform ªBasic Inspectionº, EC-98.
2. Confirm that the testing conditions indicated above are met.
3. Select ªB/FUEL SCHDLº, ªA/F ALPHA-B1º 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-141.
TROUBLE DIAGNOSIS Ð SPECIFICATION VALUEQG
Description
EC-140