2007 INFINITI M35 Mass air flow

TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-855
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
25. CHECK INTAKE SYSTEM
Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system
OK or NG
OK >> GO TO 27.
NG >> Repair or replace malfunctioning part, and then GO TO 26.
26. CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and make sure that the indication is within the
SP value.
OK or NG
OK >>INSPECTION END
NG (Less than the SP value)>>GO TO 27.
27. CHECK “MAS A/F SE-B1”
Select “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” mode, and
make sure that the indication is within the SP value.
OK or NG
OK >> GO TO 28.
NG (Less than the SP value)>>Replace mass air flow sensor, and
then GO TO 30.
28. CHECK INTAKE SYSTEM
Check for the cause of air leak after the mass air flow sensor. Refer to the following.

Disconnection, looseness, and cracks in air duct

Looseness of oil filler cap

Disconnection of oil level gauge

Open stuck, breakage, hose disconnection, or cracks of PCV valve

Disconnection or cracks of EVAP purge hose, open stuck of EVAP canister purge volume control solenoid
valve

Malfunctioning seal of rocker cover gasket

Disconnection, looseness, or cracks of hoses, such as vacuum hose, connecting to intake air system
parts

Malfunctioning seal of intake air system, etc.
>> GO TO 30.
29. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”, AND “B/FUEL SCHDL”
Select “A/F ALPHA-B1”, “A/F ALPHA-B2”, and “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and
make sure that the each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> Detect malfunctioning part according to EC-801, "
Symptom Matrix Chart" .
PBIB2370E

DTC P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER
EC-883
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
DTC P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATERPFP:22693
DescriptionNBS005BH
SYSTEM DESCRIPTION
The ECM performs ON/OFF duty control of the A/F sensor 1 heater corresponding to the engine operating
condition to keep the temperature of A/F sensor 1 element at the specified range.
CONSULT-II Reference Value in Data Monitor ModeNBS005BI
Specification data are reference values.
On Board Diagnosis LogicNBS005BJ
DTC Confirmation ProcedureNBS005BK
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 11V and 16V at
idle.
WITH CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Wait at least 5 seconds.
3. If 1st trip DTC is detected, go to EC-887, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Sensor Input Signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Air fuel ratio (A/F) sensor 1
heater controlAir fuel ratio (A/F) sensor 1
heater
Mass air flow sensor Amount of intake air
MONITOR ITEM CONDITION SPECIFICATION
A/F S1 HTR (B1)
A/F S1 HTR (B2)

Engine: After warming up, idle the engine 0 - 100%
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0031
0031
(Bank 1)
Air fuel ratio (A/F) sensor 1
heater control circuit lowThe current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the A/F sensor 1 heater.)

Harness or connectors
(The A/F sensor 1 heater circuit is
open or shorted.)

A/F sensor 1 heater P0051
0051
(Bank 2)
P0032
0032
(Bank 1)
Air fuel ratio (A/F) sensor 1
heater control circuit highThe current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the A/F sensor 1 heater.)

Harness or connectors
(The A/F sensor 1 heater circuit is
shorted.)

A/F sensor 1 heater P0052
0052
(Bank 2)
SEF058Y

EC-890
[VK45DE]
DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
Revision: 2007 April2007 M35/M45
DTC P0037, P0038, P0057, P0058 HO2S2 HEATERPFP:226A0
DescriptionNBS005BP
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
OPERATION
CONSULT-II Reference Value in Data Monitor ModeNBS005BQ
Specification data are reference values.
On Board Diagnosis LogicNBS005BR
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Heated oxygen sensor 2
heater controlHeated oxygen sensor 2 heater
Engine coolant temperature sensor Engine coolant temperature
Mass air flow sensor Amount of intake air
Engine speed rpm Heated oxygen sensor 2 heater
Above 3,600OFF
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
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)
HO2S2 HTR (B2)

Engine speed: 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
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0037
0037
(Bank 1)
Heated oxygen sensor 2
heater control circuit lowThe current amperage in the heated oxygen
sensor 2 heater circuit is out of the normal
range.
(An excessively low voltage signal is sent to
ECM through the heated oxygen sensor 2
heater.)

Harness or connectors
(The heated oxygen sensor 2 heater circuit
is open or shorted.)

Heated oxygen sensor 2 heater P0057
0057
(Bank 2)
P0038
0038
(Bank 1)
Heated oxygen sensor 2
heater control circuit highThe current amperage in the heated oxygen
sensor 2 heater circuit is out of the normal
range.
(An excessively high voltage signal is sent
to ECM through the heated oxygen sensor 2
heater.)

Harness or connectors
(The heated oxygen sensor 2 heater circuit
is shorted.)

Heated oxygen sensor 2 heater P0058
0058
(Bank 2)

EC-906
[VK45DE]
DTC P0101 MAF SENSOR
Revision: 2007 April2007 M35/M45
DTC P0101 MAF SENSORPFP:22680
Component DescriptionNBS005C5
The mass air flow sensor (1) is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. The mass air flow sensor controls the temperature of the
hot wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor ModeNBS005C6
Specification data are reference values.
On Board Diagnosis LogicNBS005C7
PBIA9559J
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-847, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

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

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

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 circuit
range/performanceA)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

EVAP control system pressure
sensor

Intake air temperature 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

EVAP control system pressure
sensor

Intake air temperature sensor

EC-908
[VK45DE]
DTC P0101 MAF SENSOR
Revision: 2007 April2007 M35/M45
7. Maintain the following conditions for at least 10 consecutive sec-
onds.
8. If 1st trip DTC is detected, go to EC-910, "
Diagnostic Procedure"
.
Overall Function CheckNBS005C9
PROCEDURE FOR MALFUNCTION B
Use this procedure to check the overall function of the mass air flow sensor circuit. During this check, a DTC
might not be confirmed.
With GST
1. Start engine and warm it up to normal operating temperature.
2. Select Service $01 with GST.
3. Check the mass air flow sensor signal with Service $01.
4. Check for linear mass air flow sensor signal value rise in
response to increases to about 4,000 rpm in engine speed.
5. If NG, go to EC-910, "
Diagnostic Procedure" .
ENG SPEED More than 2,000 rpm
THRTL SEN 1 More than 3V
THRTL SEN 2 More than 3V
Selector lever Suitable position
Driving locationDriving vehicle uphill (Increased engine load) will help
maintain the driving conditions required for this test.
PBIB0199E
SEF534P

EC-910
[VK45DE]
DTC P0101 MAF SENSOR
Revision: 2007 April2007 M35/M45
Specification 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.
Diagnostic ProcedureNBS005CB
1. INSPECTION START
Which malfunction (A or B) is duplicated?
A or B
A >> GO TO 3.
B >> GO TO 2.
2. CHECK INTAKE SYSTEM
Check the following for connection.

Air duct

Va c u u m h o s e s

Intake air passage between air duct and intake manifold
OK or NG
OK >> GO TO 3.
NG >> Reconnect the parts.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
51 W Mass air flow sensor[Engine is running]

Warm-up condition

Idle speed0.9 - 1.2V
[Engine is running]

Warm-up condition

Engine speed: 2,500 rpm1.6 - 1.9V
67 B/WSensor ground
(MAF sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
111 S BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120R
RPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)

DTC P0101 MAF SENSOR
EC-911
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
3. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body.
Refer to EC-864, "
Ground Inspection" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace ground connections.
4. CHECK MAF SENSOR POWER SUPPLY CIRCUIT
1. Disconnect mass air flow (MAF) sensor (1) harness connector.
2. Turn ignition switch ON.
3. Check voltage between MAF sensor terminal 2 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E108, M15

Harness connectors M72, F102

Harness for open or short between mass air flow sensor and ECM

Harness for open or short between mass air flow sensor and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
1. Body ground M70 2. Body ground M16
PBIB2782E
PBIB2682E
Voltage: Battery voltage
PBIB1168E

EC-912
[VK45DE]
DTC P0101 MAF SENSOR
Revision: 2007 April2007 M35/M45
6. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between MAF sensor terminal 3 and ECM terminal 67.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between MAF sensor terminal 4 and ECM terminal 51.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK INTAKE AIR TEMPERATURE SENSOR
Refer to EC-925, "
Component Inspection" .
OK or NG
OK >> GO TO 9.
NG >> Replace intake air temperature sensor.
9. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-1138, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> Replace EVAP control system pressure sensor.
10. CHECK MASS AIR FLOW SENSOR
Refer to EC-913, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> Replace mass air flow sensor.
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-857, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.
Continuity should exist.