EC-78
[QR (WITH EURO-OBD)]
TROUBLE DIAGNOSIS
When there is an open circuit on MI circuit, the ECM can not warn the driver by lighting up MI when there is
trouble 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 has trouble and MI circuit is open by means of
operating fail-safe function.
The fail-safe function also operates when above diagnoses except MI circuit are detected and demands the
driver to repair the trouble.
P0117
P0118Engine coolant tempera-
ture sensor circuitEngine coolant temperature will be determined by ECM based on the time after turning
ignition switch ON or START.
CONSULT-II displays the engine coolant temperature decided by ECM.
ConditionEngine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned ON or START 40°C (104°F)
More than approx. 4 minutes after ignition ON
or START80°C (176°F)
Except as shown above40 - 80°C (104 - 176°F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling
fan operates while engine is running.
P0122
P0123
P0221
P0222
P2135Throttle position sensor The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.
P1121 Electric throttle control
actuator(When electric throttle control actuator does not function properly due to the return spring
malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the
idle position. The engine speed will not rise more than 2,000 rpm.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator by regulating the throttle opening to 20
degrees or less.
(ECM detect the throttle valve is stuck open:)
While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops, the
engine stalls.
The engine can restart in N or P position, and engine speed will not exceed 1,000 rpm or
more.
P1122 Electric throttle control
functionECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1124
P1126Throttle control motor relay ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1128 Throttle control motor ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1229 Sensor power supply ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2122
P2123
P2127
P2128
P2138Accelerator pedal position
sensorThe ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor. DTC No. Detected items Engine operating condition in fail-safe mode
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
TROUBLE DIAGNOSIS
EC-79
[QR (WITH EURO-OBD)]
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EC
Basic InspectionEBS010LS
1. INSPECTION START
1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
–Harness connectors for improper connections
–Wiring harness for improper connections, pinches and cut
–Vacuum hoses for splits, kinks and improper connections
–Hoses and ducts for leaks
–Air cleaner clogging
–Gasket
3. Confirm that electrical or mechanical loads are not applied.
–Headlamp switch is OFF.
–Air conditioner switch is OFF.
–Rear window defogger switch is OFF.
–Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature
indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no-
load.
6. Make sure that no DTC is displayed with CONSULT-II or GST.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2. REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnostic Procedure.
>> GO TO 3
SEF983U
SEF976U
SEF977U
EC-84
[QR (WITH EURO-OBD)]
TROUBLE DIAGNOSIS
17. DETECT MALFUNCTIONING PART
Check the following.
Check camshaft position sensor (PHASE) and circuit. Refer to EC-254 .
Check crankshaft position sensor (POS) and circuit. Refer to EC-247 .
OK or NG
OK >> GO TO 18.
NG >> 1. Repair or replace.
2. GO TO 4.
18. CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is a rare case.)
2. Perform initialization of NATS system and registration of all NATS ignition key IDs. Refer to EC-64, "
NATS
(Nissan Anti-theft System)" .
>> GO TO 4.
Symptom Matrix ChartEBS010LT
SYSTEM — BASIC ENGINE CONTROL SYSTEM
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 pump circuit 11232 22 3 2EC-443
Fuel pressure regulator system334444444 4EC-48
Injector circuit 11232 22 2EC-428
Evaporative emission system 334444444 4EC-473
Air Positive crankcase ventilation sys-
tem334444444 41EC-478
Incorrect idle speed adjustment 33 1111 1EC-79
Electric throttle control actuator 112332222 2 2EC-290
,
EC-292
,
EC-302
,
EC-310
IgnitionIncorrect ignition timing adjustment33111 11 1EC-79
Ignition circuit 11222 22 2EC-417
Main power supply and ground circuit 22333 33 23EC-124
Mass air flow sensor circuit 11222 22 2EC-149
Engine coolant temperature sensor circuit 11222322312EC-162
TROUBLE DIAGNOSIS
EC-87
[QR (WITH EURO-OBD)]
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EC
1 - 6: The numbers refer to the order of inspection.Va l v e
mecha-
nismTiming chain
55555 55 5EM-44
CamshaftEM-53
Intake valve timing controlEM-44
Intake valve
3EM-67
Exhaust valve
Exhaust Exhaust manifold/Tube/Muffler/
Gasket
55555 55 5EM-23
, EX-
2Three way catalyst
Lubrica-
tionOil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery
55555 55 52EM-25
, LU-
13 , LU-10 ,
LU-5
Oil level (Low)/Filthy oilLU-7
Cooling Radiator/Hose/Radiator filler cap
55555 55 25CO-12
Thermostat 5CO-22
Water pumpCO-20
Water galleryCO-7
Cooling fan 5CO-18
Coolant level (low)/Contaminated
coolantCO-9
NATS (Nissan Anti-theft System) 1 1EC-64 or
BL-108
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
EC-100
[QR (WITH EURO-OBD)]
TROUBLE DIAGNOSIS
62 YIntake valve timing
control solenoid valve[Engine is running]
Warm-up condition
Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Warm-up condition
Engine speed is 2,000 rpmApproximately 4V - BATTERY
VOLTAGE (11 - 14V)
65 RSensor power supply
(Power steering pressure
sensor)[Ignition switch: ON]Approximately 5V
66 BSensor ground
(Throttle position sensor)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
67 B/PSensor ground
(Mass air flow sensor)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
68 R Throttle position sensor 2[Ignition switch: ON]
Engine stopped
Shift lever: D (A/T), 1st (M/T)
Accelerator pedal: Fully releasedLess than 4.75V
[Ignition switch: ON]
Engine stopped
Shift lever: D (A/T), 1st (M/T)
Accelerator pedal: Fully depressedMore than 0.36V
69 YRefrigerant pressure sen-
sor[Engine is running]
Warm-up condition
Both A/C switch and blower switch: ON
(Compressor operates)1.0 - 4.0V
72 BR/YEngine coolant tempera-
ture sensor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with
engine coolant temperature.
73 BSensor ground
(Engine coolant tempera-
ture sensor)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
74 BSensor ground
(Heated oxygen sensor)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
82 RYSensor ground
(Accelerator pedal position
sensor 1)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
83 LSensor ground
(Accelerator pedal position
sensor 2)[Engine is running]
Warm-up condition
Idle speedApproximately 0V TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB1790E
TROUBLE DIAGNOSIS
EC-103
[QR (WITH EURO-OBD)]
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EC
*: The following emission-related diagnostic information is cleared when the ECM memory is erased.
Diagnostic trouble codes
1st trip diagnostic trouble codes
Freeze frame data
1st trip freeze frame data
System readiness test (SRT) codes
Test values
ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
DTC & SRT confirmation The status of system monitoring tests and the self-diagnosis status/result can be confirmed.
ECM part number ECM part number can be read.Diagnostic test mode Function
ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOS-
TIC RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIV
E TESTDTC & SRT
CONFIRMATION
DTC*1FREEZ
E
FRAME
DATA*
2
SRT
STA-
TUSDTC
WORK
SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS)××××
Camshaft position sensor (PHASE)×××
Mass air flow sensor×××
Engine coolant temperature sensor×××××
Heated oxygen sensor 1×××××
Heated oxygen sensor 2×××××
Vehicle speed signal××××
Accelerator pedal position sensor×××
Throttle position sensor×××
Intake air temperature sensor××××
Knock sensor×
Refrigerant pressure sensor××
Closed throttle position switch (accelera-
tor pedal position sensor signal)××
Air conditioner switch××
Park/neutral position (PNP) switch×××
Stop lamp switch×××
Power steering pressure sensor×××
Battery voltage××
Electrical load signal××
EC-106
[QR (WITH EURO-OBD)]
TROUBLE DIAGNOSIS
*: The items are the same as those of 1st trip freeze frame data.
DATA MONITOR MODE
Monitored Item
×: Applicable CAL/LD VALUE [%]
The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP [°C]
or [°F]
The engine coolant temperature at the moment a malfunction is detected is displayed.
L-FUEL TRM-B1 [%]
“Long-term fuel trim” at the moment a malfunction is detected is displayed.
The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule
than short-term fuel trim.
S-FUEL TRM-B1 [%]
“Short-term fuel trim” at the moment a malfunction is detected is displayed.
The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel
schedule.
ENGINE SPEED
[rpm]
The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED [km/
h] or [mph]
The vehicle speed at the moment a malfunction is detected is displayed.
B/FUEL SCHDL
[msec]
The base fuel schedule at the moment a malfunction is detected is displayed.
INT/A TEMP SE [°C]
or [°F]
The intake air temperature at the moment a malfunction is detected is displayed. Freeze frame data
item*Description
Monitored item
[Unit]ECM
INPUT
SIGNALSMAIN
SIG-
NALSDescription Remarks
ENG SPEED [rpm]××
Indicates the engine speed computed from the
signals of the crankshaft position sensor
(POS) and camshaft position sensor (PHASE).
Accuracy becomes poor if engine
speed drops below the idle rpm.
If the signal is interrupted while the
engine is running, an abnormal
value may be indicated.
MAS A/F SE-B1 [V]××
The signal voltage of the mass air flow sensor
is displayed.When the engine is stopped, a
certain value is indicated.
B/FUEL SCHDL
[msec]×
“Base fuel schedule” indicates the fuel injec-
tion pulse width programmed into ECM, prior
to any learned on board correction.
A/F ALPHA-B1 [%]×
The mean value of the air-fuel ratio feedback
correction factor per cycle is indicated.
When the engine is stopped, a
certain value is indicated.
This data also includes the data
for the air-fuel ratio learning con-
trol.
COOLAN TEMP/S
[°C] or [°F]××
The engine coolant temperature (determined
by the signal voltage of the engine coolant
temperature sensor) is displayed.
When the engine coolant tempera-
ture sensor is open or short-cir-
cuited, ECM enters fail-safe mode.
The engine coolant temperature
determined by the ECM is dis-
played.
HO2S1 (B1) [V]××
The signal voltage of the heated oxygen sen-
sor 1 is displayed.
HO2S2 (B1) [V]×
The signal voltage of the heated oxygen sen-
sor 2 is displayed.
EC-110
[QR (WITH EURO-OBD)]
TROUBLE DIAGNOSIS
ACTIVE TEST MODE
Test Item
*1:Leaving cooling fan OFF with CONSULT-II while engine is running may cause the engine to overheat.
DTC & SRT CONFIRMATION MODE
SRT STATUS Mode
For details, refer to EC-55, "SYSTEM READINESS TEST (SRT) CODE" .
SRT WORK SUPPORT Mode
This mode enables a technician to drive a vehicle to set the SRT while monitoring the SRT status.
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION
Engine: Return to the original
trouble condition
Change the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
Harness and connectors
Fuel injector
Heated oxygen sensor 1
IGNITION TIM-
ING
Engine: Return to the original
trouble condition
Timing light: Set
Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
Perform Idle Air Volume Learning.
POWER BAL-
ANCE
Engine: After warming up, idle
the engine.
Air conditioner switch: OFF
Shift lever: N (A/T), Neutral (M/T)
Cut off each injector signal one at
a time using CONSULT-II.Engine runs rough or dies.
Harness and connectors
Compression
Fuel injector
Power transistor
Spark plug
Ignition coil
COOLING FAN*
1
Ignition switch: ON
Turn the cooling fan LOW, HI,
OFF with CONSULT-II.Cooling fan moves and stops.
Harness and connectors
Cooling fan relay
Cooling fan motor
ENG COOLANT
TEMP
Engine: Return to the original
trouble condition
Change the engine coolant tem-
perature using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
Harness and connectors
Engine coolant temperature sen-
sor
Fuel injector
FUEL PUMP
RELAY
Ignition switch: ON (Engine
stopped)
Turn the fuel pump relay ON and
OFF using CONSULT-II and lis-
ten to operating sound.Fuel pump relay makes the operat-
ing sound.Harness and connectors
Fuel pump relay
VIAS SOL VALVE
Ignition switch: ON
Turn solenoid valve ON and OFF
with CONSULT-II and listen for
operating sound.Solenoid valve makes an operating
sound.Harness and connectors
Solenoid valve
PURG VOL
CONT/V
Engine: After warming up, run
engine at 1,500 rpm.
Change the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT-II.Engine speed changes according to
the opening percent.Harness and connectors
Solenoid valve
V/T ASSIGN
ANGLE
Engine: Return to the original
trouble condition
Change intake valve timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
Harness and connectors
Intake valve timing control sole-
noid valve