2008 INFINITI FX35 ignition

EC-586
< SERVICE INFORMATION >[VQ35DE]
SNOW MODE SWITCH
SNOW MODE SWITCH
DescriptionINFOID:0000000001326464
The snow mode switch signal is sent to the “unifi
ed meter and A/C amp.” from the snow mode switch. The
“unified meter and A/C amp.” then sends the signal to the ECM by CAN communication line.
The snow mode is used for driving or starting the vehicle on snowy roads or slippery areas. If the snow mode
is activated, the vehicle speed will not be accelerated i mmediately than your original pedal in due to avoid the
vehicle slip. In other words, ECM controls the rapi d engine torque change by controlling the electric throttle
control actuator operating speed.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326465
MONITOR ITEM CONDITION SPECIFICATION
SNOW MODE SW  Ignition switch: ON Snow mode switch: ON ON
Snow mode switch: OFF OFF
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SNOW MODE SWITCHEC-587
< SERVICE INFORMATION > [VQ35DE]
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Wiring DiagramINFOID:0000000001326466
Diagnosis ProcedureINFOID:0000000001326467
1.CHECK SNOW MODE SWIT
ICH OVERALL FUNCTION-I
1. Turn ignition switch ON.
2. Select “SNOW MODE SW” in “DAT A MONITOR” mode with CONSULT-III.
3. Check “SNOW MODE SW” indication under the following conditions.
TBWM1415E
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EC-588
< SERVICE INFORMATION >[VQ35DE]
SNOW MODE SWITCH
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2.CHECK SNOW MODE SWIT
ICH OVERALL FUNCTION-II
1. Turn ignition switch ON.
2. Start engine.
3. Check the snow mode indicator in the snow mode switch under the following condition.
OK or NG
OK >> INSPECTION END
NG >> GO TO 7.
3.CHECK DTC WITH “UNIFIED METER AND A/C AMP.”
Refer to DI-27, "
CONSULT-III Function (METER/M&A)".
OK or NG
OK >> GO TO 4.
NG >> Go to DI-26
.
4.CHECK SNOW MODE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect snow mode switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between snow mode switch terminal 1 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
 Fuse block (J/B) M1
 10A fuse
 Harness for open or short between snow mode switch and fuse.
>> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK SNOW MODE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “unified meter and A/C amp.” harness connector.
3. Check harness continuity between snow mode switch terminal 4 and “unified meter and A/C amp.” termi-
nal 12. Refer to Wiring Diagram.
CONDITION INDICATION
Snow mode switch: ON ON
Snow mode switch: OFF OFF
CONDITION INDICATOR
Snow mode switch: ON Illuminated
Snow mode switch: OFF Not illuminated
Voltage: Battery voltage.
PBIB2562E
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SNOW MODE SWITCHEC-589
< SERVICE INFORMATION > [VQ35DE]
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4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-723, "
Ground Inspection".
OK or NG
OK >> GO TO 8.
NG >> Repair or replace ground connections.
8.CHECK SNOW MODE INDICATOR LAMP GROUND CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between snow mode switch terminal 2 and ground. Refer to Wiring Diagram.
2. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to power in harness or connectors.
9.CHECK SNOW MODE SWITCH
Refer to EC-1185, "
Component Inspection".
OK or NG
OK >> GO TO 10.
NG >> Replace snow mode switch.
10.CHECK INTERMITTENT INCIDENT
Refer to EC-717
.
>> INSPECTION END
Component InspectionINFOID:0000000001326468
SNOW MODE SWITCH
Continuity should exist.
PBIB2625E
Continuity should exist.
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SERVICE DATA AND SPECIFICATIONS (SDS)
EC-593
< SERVICE INFORMATION > [VQ35DE]
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SERVICE DATA AND SPECIFICATIONS (SDS)
Fuel PressureINFOID:0000000001326470
Idle Speed and Ignition TimingINFOID:0000000001326471
*1: Under the following conditions:
 Air conditioner switch: OFF
 Electric load: OFF (Lights, heater fan & rear window defogger)
 Steering wheel: Kept in straight-ahead position
Calculated Load ValueINFOID:0000000001326472
Mass Air Flow SensorINFOID:0000000001326473
*: Engine is warmed up to normal operating temperature and running under no load.
Intake Air Temperature SensorINFOID:0000000001326474
Engine Coolant Temperature SensorINFOID:0000000001326475
Air Fuel Ratio (A/F) Sensor 1 HeaterINFOID:0000000001326476
Heated Oxygen sensor 2 HeaterINFOID:0000000001326477
Fuel pressure at idling kPa (kg/cm2, psi)
Approximately 350 (3.57, 51)
Target idle speed
No load*1 (in P or N position) 650
±50 rpm
Air conditioner: ON In P or N position 700 rpm or more
Ignition timing In P or N position 15 ° ± 5 ° BTDC
Calculated load value% (Using CONSULT-III or GST)
At idle 5 - 35
At 2,500 rpm 5 - 35
Supply voltageBattery voltage (11 - 14V)
Output voltage at idle 1.0 - 1.2V*
Mass air flow (Using CONSULT-III or GST) 2.0 - 6.0 g·m/sec at idle*
7.0 - 20.0 g·m/sec at 2,500 rpm*
Temperature °C ( °F) Resistance k Ω
25 (77) 1.800 - 2.200
Temperature °C ( °F) Resistance k Ω
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
Resistance [at 25°C (77 °F)] 2.3 - 4.3 Ω
Resistance [at 25°C (77 °F)] 3.4 - 4.4 Ω
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PRECAUTIONSEC-603
< SERVICE INFORMATION > [VK45DE]
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PRECAUTIONS
Precaution for Supplemental
Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000001612919
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SUPPLEMENTAL RESTRAINT SYS-
TEM” and “SEAT BELTS” of this Service Manual.
WARNING:
 To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SUPPLEMEN TAL RESTRAINT SYSTEM”.
 Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
Precaution for Procedur e without Cowl Top CoverINFOID:0000000001612941
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.
On Board Diagnosis (OBD) System of Engine and A/TINFOID:0000000001326487
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
 Be sure to turn the ignition switch OFF and di sconnect the negative battery cable before any repair
or inspection work. The op en/short circuit of related switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
 Be sure to connect and lock the connectors secure ly after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
 Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For descripti on and how to disconnect, refer to PG-68
.
 Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to li ght up due to the short circuit.
 Be sure to connect rubber tubes properly afte r work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfuncti on of the EVAP system or fuel injection system,
etc.
 Be sure to erase the unnecessary ma lfunction information (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
PIIB3706J
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EC-604
< SERVICE INFORMATION >[VK45DE]
PRECAUTIONS
Precaution
INFOID:0000000001326488
 Always use a 12 volt battery as power source.
 Do not attempt to disconnect battery cables while engine is
running.
 Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
 Before removing parts, turn ig nition switch OFF and then dis-
connect battery ground cable.
 Do not disassemble ECM.
 If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-c ontrol at its initial value.
Engine operation can vary slight ly when the terminal is dis-
connected. However, this is no t an indication of a malfunc-
tion. Do not replace parts b ecause of a slight variation.
 If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
 When connecting ECM harness connector, fasten (B) it
securely with a lever (2) as far as it will go as shown in the fig-
ure.
- ECM (1)
- Loosen (A)
 When connecting or disconnect ing pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM pin
terminal, when connecting pin connectors.
 Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge) volt-
age to develop in coil and co ndenser, thus resulting in dam-
age to ICs.
 Keep engine control system harn ess at least 10 cm (4 in) away
from adjacent harness, to preven t engine control system mal-
functions due to receiving exter nal noise, degraded operation
of ICs, etc.
 Keep engine control system parts and harness dry.
SEF289H
PBIB1164E
PBIB3223E
PBIB0090E
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EC-612
< SERVICE INFORMATION >[VK45DE]
ENGINE CONTROL SYSTEM
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration,
operation of the engine at excessively high speeds or oper-
ation of the vehicle at excessively high speeds.
Electronic Ignition (EI) SystemINFOID:0000000001326493
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
Firing order: 1 - 8 - 7 - 3 - 6 - 5 - 4 - 2
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition si gnals are transmitted to the power transistor.
During the following conditions, the ignition timing is re vised by the ECM according to the other data stored in
the ECM.
 At starting
 During warm-up
 At idle
 At low battery voltage
 During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Fuel Cut Control (at No Load and High Engine Speed)INFOID:0000000001326494
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
2
Piston position
Ignition timing
controlPower transistor
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Battery
Battery voltage*
2
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Wheel sensor
Vehicle speed*
1
Sensor Input Signal to ECM ECM function Actuator
Park/neutral position (P NP) switch Neutral position
Fuel cut control Fuel injector
Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
Engine speed
Wheel sensor Vehicle speed*
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