light INFINITI FX35 2004 Service Manual

TROUBLE DIAGNOSIS
EC-737
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Revision: 2004 November 2004 FX35/FX45
15. CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light.
OK or NG
OK >>INSPECTION END
NG >> GO TO 16.
16. CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-196, "
TIMING CHAIN" .
OK or NG
OK >> GO TO 17.
NG >> 1. Repair the timing chain installation.
2. GO TO 4.
17. DETECT MALFUNCTIONING PART
Check the following.

Check camshaft position sensor (PHASE) and circuit. Refer to EC-966 .

Check crankshaft position sensor (POS) and circuit. Refer to EC-960 .
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 IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to
EC-717, "
IVIS (Infiniti Vehicle Immobilizer System — NATS)" .
>> GO TO 4. 12 ± 5° BTDC (in P or N position)
PBIB1487E

EC-766
[VK45DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
BATTERY VOLT [V]××
The power supply voltage of ECM is dis-
played.
ACCEL SEN 1 [V]××

The accelerator pedal position sensor sig-
nal voltage is displayed.
ACCEL SEN 2 signal is converted be
ECM internally. Thus, they differs
from ECM terminal voltage signal. ACCEL SEN 2 [V]×
THRTL SEN 1 [V]××

The throttle position sensor signal voltage
is displayed.
THRTL SEN 2 signal is converted by
ECM internally. Thus, they differs
from ECM terminal voltage signal. THRTL SEN 2 [V]×
FUEL T/TEMP SE
[°C] or [°F]×

The fuel temperature (determined by the
signal voltage of the fuel tank temperature
sensor) is displayed.
INT/A TEMP SE
[°C] or [°F]××

The intake air temperature (determined by
the signal voltage of the intake air tempera-
ture sensor) is indicated.
EVAP SYS PRES [V]×

The signal voltage of EVAP control system
pressure sensor is displayed.
FUEL LEVEL SE [V]×

The signal voltage of the fuel level sensor is
displayed.
START SIGNAL
[ON/OFF]××

Indicates start signal status [ON/OFF] com-
puted by the ECM according to the signals
of engine speed and battery voltage.
After starting the engine, [OFF] is dis-
played regardless of the starter sig-
nal.
CLSD THL POS
[ON/OFF]××

Indicates idle position [ON/OFF] computed
by ECM according to the accelerator pedal
position sensor signal.
AIR COND SIG
[ON/OFF]××

Indicates [ON/OFF] condition of the air con-
ditioner switch as determined by the air
conditioner signal.
P/N POSI SW
[ON/OFF]××

Indicates [ON/OFF] condition from the park/
neutral position (PNP) switch signal.
PW/ST SIGNAL
[ON/OFF]××

[ON/OFF] condition of the power steering
system (determined by the signal voltage of
the power steering pressure sensor signal)
is indicated.
LOAD SIGNAL
[ON/OFF]××

Indicates [ON/OFF] condition from the elec-
trical load signal.
ON: Rear window defogger switch is ON
and/or lighting switch is in 2nd position.
OFF: Both rear window defogger switch
and lighting switch are OFF.
SNOW MODE SW
[ON/OFF]

Indicates [ON/OFF] condition from the
snow mode switch signal.
IGNITION SW
[ON/OFF]×

Indicates [ON/OFF] condition from ignition
switch signal.
HEATER FAN SW
[ON/OFF]×

Indicates [ON/OFF] condition from the
heater fan switch signal.
BRAKE SW
[ON/OFF]

Indicates [ON/OFF] condition from the stop
lamp switch signal.
INJ PULSE-B1
[msec]×

Indicates the actual fuel injection pulse
width compensated by ECM according to
the input signals.
When the engine is stopped, a cer-
tain computed value is indicated.
INJ PULSE-B2
[msec]Monitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

TROUBLE DIAGNOSIS
EC-769
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Revision: 2004 November 2004 FX35/FX45
DATA MONITOR (SPEC) MODE
Monitored Item
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
ENG SPEED [rpm]××

Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS) and camshaft position
sensor (PHASE).
MAS A/F SE-B1 [V]××

The signal voltage of the mass air flow
sensor specification is displayed.
When engine is running specification
range is indicated.
B/FUEL SCHDL
[msec]×

“Base fuel schedule” indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.

When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]
A/F ALPHA-B2 [%]×

The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.
When engine is running specification
range is indicated.

This data also includes the data for the
air-fuel ratio learning control.
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.

A/C switch OFF

Shift lever: N

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*

Ignition switch: ON

Turn the cooling fan “HI” and
“OFF” using CONSULT-II.Cooling fan moves and stops.

Harness and connectors

Cooling fan motor

IPDM E/R
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

TROUBLE DIAGNOSIS
EC-775
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Revision: 2004 November 2004 FX35/FX45
CONSULT-II Reference Value in Data MonitorABS00BZZ
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.
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED

Run engine and compare the CONSULT-II value with tachometer indica-
tionAlmost the same speed as the
tachometer indication
MAS A/F SE-B1 See EC-780, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
B/FUEL SCHDL See EC-780, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
A/F ALPHA-B1
A/F ALPHA-B2See EC-780, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
COOLAN TEMP/S

Engine: After warming up More than 70°C (158°F)
HO2S1 (B1)
HO2S1 (B2)

Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 (B1)
HO2S2 (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no loadRevving engine from idle to 3,000 rpm
quickly0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S1 MNTR (B1)
HO2S1 MNTR (B2)

Engine: After warming upMaintaining engine speed at 2,000
rpmLEAN ←→ RICH
Changes more than 5 times
during 10 seconds
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no loadRevving engine from idle to 3,000 rpm
quicklyLEAN ←→ RICH
VEH SPEED SE

Turn drive wheels and compare the CONSULT-II value with speedometer
indicationAlmost the same speed as the
speedometer indication
BATTERY VOLT

Ignition switch: ON (Engine stopped) 11 - 14V
ACCEL SEN1

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.7V
ACCEL SEN2*

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.3 - 1.2V
Accelerator pedal: Fully depressed 3.9 - 4.8V
THRTL SEN1
THRTL SEN2*

Ignition switch: ON
(Engine stopped)

Shift lever: DAccelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
EVAP SYS PRES

Ignition switch: ON Approx. 1.8 - 4.8V
START SIGNAL

Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG

Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates)ON
P/N POSI SW

Ignition switch: ONShift lever: P or N ON
Shift lever: Except above OFF
PW/ST SIGNAL

Engine: After warming up, idle
the engineSteering wheel is in neutral position
(Forward direction)OFF
Steering wheel is turned ON

EC-776
[VK45DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
LOAD SIGNAL
Ignition switch: ONRear window defogger switch is ON
and/or lighting switch is in 2ndON
Rear window defogger switch is OFF
and lighting switch is OFFOFF
SNOW MODE SW

Ignition switch: ONSnow mode switch: ON ON
Snow mode switch: OFF OFF
IGNITION SW

Ignition switch: ON → OFF → ON ON → OFF → ON
HEATER FAN SW

Engine: After warming up, idle
the engineHeater fan is operating ON
Heater fan is not operating OFF
BRAKE SW

Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
INJ PULSE-B1
INJ PULSE-B2

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 2.0 - 3.0 msec
2,000 rpm 1.9 - 2.9 msec
IGN TIMING

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 10° - 14° BTDC
2,000 rpm 25° - 45° BTDC
CAL/LD VALUE

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
PURG VOL C/V

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 0%
2,000 rpm —
INT/V TIM (B1)
INT/V TIM (B2)

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle−5° - 5°CA
2,000 rpm Approx. 0° - 20°CA
INT/V SOL (B1)
INT/V SOL (B2)

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 0% - 2%
2,000 rpm Approx. 25% - 50%
VIAS S/V

Engine speed: IdleShift lever position: P or N ON
Except above OFF
AIR COND RLY

Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates)ON
FUEL PUMP RLY

For 1 second after turning ignition switch ON

Engine running or crankingON

Except above conditions OFF MONITOR ITEM CONDITION SPECIFICATION

TROUBLE DIAGNOSIS
EC-777
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Revision: 2004 November 2004 FX35/FX45
*: Accelerator pedal position sensor 2 signal and throttle position sensor 2 signal are converted by ECM internally. Thus, they differ from
ECM terminals voltage signal.VENT CONT/V

Ignition switch: ON OFF
THRTL RELAY

Ignition switch: ON ON
COOLING FAN

Engine: After warming up, idle
the engine

Air conditioner switch: OFFEngine coolant temperature is 94°C
(201°F) or lessOFF
Engine coolant temperature is 95°C
(203°F) or moreHI
HO2S1 HTR (B1)
HO2S1 HTR (B2)

Engine: After warming up

Engine speed: Below 3,000 rpmON

Engine speed: Above 3,000 rpm OFF
HO2S2 HTR (B1)
HO2S2 HTR (B2)

Engine speed is below 3,600 rpm after the following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no loadON

Engine speed: Above 3,600 rpm OFF
I/P PULLY SPD

Vehicle speed: More than 20 km/h (12 MPH)Almost the same speed as the
tachometer indication
VEHICLE SPEED

Turn drive wheels and compare the CONSULT-II value with speedometer
indicationAlmost the same speed as the
speedometer indication
TRVL AFTER MIL

Ignition switch: ONVehicle has traveled after MIL has
turned ON.0 - 65,535 km
(0 - 40,723 miles)
O2SEN HTR DTY

Engine coolant temperature when engine started: More than 80°C (176°F)

Engine speed: Below 3,000 rpmApprox. 40%
AC PRESS SEN

Engine: Idle

Both A/C switch and blower fan switch: ON (Compressor operates)1.0 - 4.0V
VEH SPEED SE

Turn drive wheels and compare the CONSULT-II value with speedometer
indicationAlmost the same speed as the
speedometer indication
SET VHCL SPD

Engine: Running ASCD: OperatingThe preset vehicle speed is
displayed
MAIN SW

Ignition switch: ONON/OFF (MAIN) switch: Pressed ON
ON/OFF (MAIN) switch: Released OFF
CANCEL SW

Ignition switch: ONCANCEL switch: Pressed ON
CANCEL switch: Released OFF
RESUME/ACC SW

Ignition switch: ONACCEL/RESUME switch: Pressed ON
ACCEL/RESUME switch: Released OFF
SET SW

Ignition switch: ONCOAST/SET switch: Pressed ON
COAST/SET switch: Released OFF
BRAKE SW1

Ignition switch: ONBrake pedal: Fully released ON
Brake pedal: Slightly depressed OFF
BRAKE SW2

Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DIST SW

Ignition switch: ONDISTANCE switch: Pressed ON
DISTANCE switch: Released OFF
CRUISE LAMP

Ignition switch: ONON/OFF (MAIN) switch: Pressed at
the 1st time → at the 2nd timeON → OFF
SET LAMP

Ignition switch: ONASCD is operating ON
ASCD is not operating OFF MONITOR ITEM CONDITION SPECIFICATION

EC-780
[VK45DE]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Revision: 2004 November 2004 FX35/FX45
TROUBLE DIAGNOSIS - SPECIFICATION VALUEPFP:00031
DescriptionABS00C01
The specification (SP) value indicates the tolerance of the value that is displayed in “DATA MONITOR (SPEC)”
mode of CONSULT-II during normal operation of the Engine Control System. When the value in “DATA MONI-
TOR (SPEC)” mode is within the SP value, the Engine Control System is confirmed OK. When the value in
“DATA MONITOR (SPEC)” 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/B2 (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 ConditionABS00C02

Vehicle driven distance: More than 5,000 km (3,017 miles)

Barometric pressure: 98.3 - 104.3 kPa (1.003 - 1.064 kg/cm2 , 14.25 - 15.12 psi)

Atmospheric temperature: 20 - 30°C (68 - 86°F)

Engine coolant temperature: 75 - 95°C (167 - 203°F)

Transmission: Warmed-up*1

Electrical load: Not applied*2

Engine speed: Idle
*1: After the engine is warmed up to normal operating temperature, drive vehicle until “FLUID TEMP SE” (A/T
fluid temperature sensor signal) indicates more than 60°C (140°F).
*2: Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.
Inspection ProcedureABS00C03
NOTE:
Perform “DATA MONITOR (SPEC)” mode in maximum scale display.
1. Perform EC-733, "
Basic Inspection" .
2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2”
and “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” mode with
CONSULT-II.
4. Make sure that monitor items are within the SP value.
5. If NG, go to EC-781, "
Diagnostic Procedure" .
SEF601Z

EC-792
[VK45DE]
DTC U1000, U1001 CAN COMMUNICATION LINE
Revision: 2004 November 2004 FX35/FX45
DTC U1000, U1001 CAN COMMUNICATION LINEPFP:23710
DescriptionABS00C0A
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.
On Board Diagnosis LogicABS00C0B
*1: This self-diagnosis has the one trip detection logic.
*2: The MIL will not light up for this diagnosis.
DTC Confirmation ProcedureABS00C0C
1. Turn ignition switch ON and wait at least 3 seconds.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. If 1st trip DTC is detected, go to EC-794, "
Diagnostic Procedure" .
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
U1000*
1
1000*1CAN communication
line

ECM cannot communicate to other control
units.

ECM cannot communicate for more than the
specified time.

Harness or connectors
(CAN communication line is open or
shorted) U1001*
2
1001*2

EC-822
[VK45DE]
DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC P0101 MAF SENSORPFP:22680
Component DescriptionABS00C13
The mass air flow sensor is placed in the stream of intake air. It mea-
sures the intake flow rate by measuring a part of the entire intake
flow. It consists of a hot film that is supplied with electric current from
the ECM. The temperature of the hot film is controlled by the ECM a
certain amount. The heat generated by the hot film is reduced as the
intake air flows around it. The more air, the greater the heat loss.
Therefore, the ECM must supply more electric current to maintain
the temperature of the hot film as air flow increases. The ECM
detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor ModeABS00C14
Specification data are reference values.
On Board Diagnosis LogicABS00C15
This self-diagnosis has the one trip detection logic.
NOTE:
If DTC P0101 is displayed with DTC P1229, first perform the trouble diagnosis for DTC P1229. Refer to
EC-1156
.
SEC266C
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-780, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0101
0101Mass air flow sensor cir-
cuit range/performance
problemA)A high voltage from the sensor is sent to ECM
under light load driving condition.

Harness or connectors
(The sensor circuit is open or
shorted.)

Mass air flow sensor
B)A low voltage from the sensor is sent to ECM
under heavy load driving condition.

Harness or connectors
(The sensor circuit is open or
shorted.)

Intake air leaks

Mass air flow sensor

EC-830
[VK45DE]
DTC P0102, P0103 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC P0102, P0103 MAF SENSORPFP:22680
Component DescriptionABS00C1C
The mass air flow sensor is placed in the stream of intake air. It mea-
sures the intake flow rate by measuring a part of the entire intake
flow. It consists of a hot film that is supplied with electric current from
the ECM. The temperature of the hot film is controlled by the ECM a
certain amount. The heat generated by the hot film is reduced as the
intake air flows around it. The more air, the greater the heat loss.
Therefore, the ECM must supply more electric current to maintain
the temperature of the hot film as air flow increases. The ECM
detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor ModeABS00C1D
Specification data are reference values.
On Board Diagnosis LogicABS00C1E
These self-diagnoses have the one trip detection logic.
NOTE:
If DTC P0102 or P0103 is displayed with DTC P1229, first perform the trouble diagnosis for DTC P1229.
Refer to EC-1156
.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
SEC266C
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-780, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0102
0102Mass air flow sensor
circuit low inputAn excessively low voltage from the sensor is
sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Intake air leaks

Mass air flow sensor
P0103
0103Mass air flow sensor
circuit high inputAn excessively high voltage from the sensor is
sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Mass air flow sensor
Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.