2004 INFINITI FX35 control

PRECAUTIONS
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Revision: 2004 November 2004 FX35/FX45
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
ADS000RH
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity 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 SRS and SB section of this Service Man-
ual.
WARNING:

To avoid rendering the SRS inoperative, 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 per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
PrecautionsADS000RI

Before connecting or disconnecting the AWD control unit
harness connector, turn ignition switch “OFF” and discon-
nect negative battery cable. Because battery voltage is
applied to AWD control unit even if ignition switch is turned
“OFF”.

When connecting or disconnecting pin connectors into or
from AWD control unit, take care not to damage pin termi-
nals (bend or break).
When connecting pin connectors, make sure that there are
no bends or breaks on AWD control unit pin terminal.

Before replacing AWD control unit, perform AWD control
unit input/output signal inspection and make sure whether
AWD control unit functions properly or not. Refer to TF-19,
"AWD Control Unit Input/Output Signal Reference Values" .
SEF289H
SEF291H
SDIA1848E

AWD SYSTEM
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Revision: 2004 November 2004 FX35/FX45
AWD SYSTEMPFP:41650
Power Transfer DiagramADS000RV
System DescriptionADS000RW
DESCRIPTION

Electronic control allows optimal distribution of torque to front/rear wheels to match road conditions.

Makes possible stable driving, with no wheel spin, on snowy roads or other slippery surfaces.

On roads which do not require AWD, it contributes to improved fuel economy by driving in conditions close
to rear-wheel drive.

Sensor inputs determine the vehicle's turning condition, and in response tight cornering/braking are con-
trolled by distributing optimum torque to front wheels.
NOTE:

When driving, if there is a large difference between front and rear wheel speed which continues for a long
time, fluid temperature of drive system parts becomes too high and AWD warning lamp flashes rapidly.
(When AWD warning lamp flashes, vehicle changes to rear-wheel drive conditions.) Also, optional distri-
bution of torque sometimes becomes rigid before lamp flashes rapidly, but it is not malfunction.

If AWD warning lamp is flashing rapidly, stop vehicle and allow it to idle for some time. Flashing will stop
and AWD system will be restored.

When driving, AWD warning lamp may flash slowly if there is a significant difference in diameter of the
tires. At this time, vehicle performance is not fully available and cautious driving is required. (Continues
until engine is turned OFF.)

If the warning lamp flashes slowly during driving but remains OFF after engine is restarted, the system is
normal. If it again flashes slowly after driving for some time, vehicle must be inspected.

When the difference of revolution speed between the front and rear wheel with AUTO mode the shift occa-
sionally changes to direct 4-wheel driving conditions automatically. This is not malfunction.
SDIA1611E

TF-10
AWD SYSTEM
Revision: 2004 November 2004 FX35/FX45
ELECTRIC CONTROLLED COUPLING
Operation principle
1. AWD control unit supplies command current to electric controlled coupling (AWD solenoid).
2. Control clutch is engaged by electromagnet and torque is detected in control clutch.
3. The cam operates in response to control clutch torque and applies pressure to main clutch.
4. Main clutch transmits torque to front wheels according to pressing power.

Transmission torque to front wheels is determined according
to command current.
AWD CONTROL UNIT

Controls distribution of drive power between rear-wheel drive
(0:100) and AWD (50:50) conditions according to signals from
sensors.

Self-diagnosis can be done with CONSULT-II.
SDIA2270E
SDIA1844E
SDIA2273E

TF-12
AWD SYSTEM
Revision: 2004 November 2004 FX35/FX45
COMPONENTS FUNCTION DESCRIPTION
CAN CommunicationADS000RY
SYSTEM DESCRIPTION
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.
For details, refer to LAN-6, "
CAN Communication Unit" .
Component parts Function
AWD control unit

Controls driving force distribution by signals from each sensor and switch from rear wheel driving
mode (0:100) to AWD mode (50:50).

2WD mode is available by fail-safe function if malfunction is detected in AWD system.
Wheel sensors Detects wheel speed.
AWD solenoid Controls electric controlled coupling by command current from AWD control unit.
Electric controlled coupling Transmits driving force to front final drive.
AWD warning lamp

Illuminates if malfunction is detected in electrical system of AWD system.

There is 1 blink in 2 seconds if rotation difference of front wheels and rear wheels is large.

There are 2 blinks in 1 second if load is still applied to driving parts.
ABS actuator and electric unit
(control unit)Transmits the following signals via CAN communication to AWD control unit.

Vehicle speed signal

Stop lamp switch signal (brake signal)
ECMTransmits the following signals via CAN communication to AWD control unit.

Accelerator pedal position signal

Engine speed signal
Unified meter and A/C amp. Transmits conditions of parking brake switch via CAN communication to AWD control unit.

TROUBLE DIAGNOSIS
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Revision: 2004 November 2004 FX35/FX45
TROUBLE DIAGNOSISPFP:00004
Fail-Safe FunctionADS000S1

If any malfunction occurs in AWD electrical system, and control unit detects the malfunction, AWD warn-
ing lamp on combination meter turns ON to indicate system malfunction.

When AWD warning lamp is ON, vehicle changes to rear-wheel drive or shifting driving force-AWD (Front-
wheels still have some driving torque).
How to Perform Trouble DiagnosisADS000S2
BASIC CONCEPT

To perform trouble diagnosis, it is the most important to have understanding about vehicle systems (con-
trol and mechanism) thoroughly.

It is also important to clarify customer complaints before inspec-
tion.
First of all, reproduce symptoms, and understand them fully.
Ask customer about his/her complaints carefully. In some cases,
it will be necessary to check symptoms by driving vehicle with
customer.
CAUTION:
Customers are not professional. It is dangerous to make an
easy guess like "maybe the customer means that...," or
"maybe the customer mentions this symptom".

It is essential to check symptoms right from the beginning in
order to repair malfunctions completely.
For intermittent malfunctions, reproduce symptoms based on
interview with customer and past examples. Do not perform
inspection on ad hoc basis. Most intermittent malfunctions are
caused by poor contacts. In this case, it will be effective to shake
suspected harness or connector by hand. When repairing with-
out any symptom diagnosis, you cannot judge if malfunctions
have actually been eliminated.

After completing diagnosis, always erase diagnostic memory.
Refer to TF-22, "
How to Erase Self-diagnostic Results" .

For intermittent malfunctions, move harness or harness connec-
tor by hand. Then check for poor contact or reproduced open circuit.
SEF233G
SEF234G

TROUBLE DIAGNOSIS
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Revision: 2004 November 2004 FX35/FX45
Trouble Diagnosis Chart for SymptomsADS000S3
If AWD warning lamp turns ON, perform self-diagnosis. Refer to TF-21, "SELF-DIAG RESULT MODE" .
NOTE:
Light tight-corner braking symptom may occur depending on driving conditions. This is not malfunction.
AWD Control Unit Input/Output Signal Reference ValuesADS000S4
AWD CONTROL UNIT INSPECTION TABLE
Specifications with CONSULT-II
Symptom Condition Check items Reference page
AWD warning lamp does not turn ON when
the ignition switch is turned to ON.
(AWD warning lamp check)Ignition switch: ONCAN communication line
TF-32
Unified meter and A/C amp.
Unified meter control unit
AWD warning lamp does not turn OFF sev-
eral seconds after engine started.Engine runningCAN communication line
TF-32
Power supply and ground for AWD con-
trol unit
Unified meter and A/C amp.
Unified meter control unit
AWD solenoid
AWD actuator relay (integrated in AWD
control unit)
Wheel sensor
Heavy tight-corner braking symptom occurs
when the vehicle is driven and the steering
wheel is turned fully to either side after the
engine is started. (See NOTE.)

While driving

Steering wheel is
turned fully to either
sidesCAN communication line
TF-34Accelerator pedal position signal
AWD solenoid
Mechanical malfunction of electric con-
trolled coupling (clutch sticking etc.)
Vehicle does not enter AWD mode even
though AWD warning lamp turned to OFF.While drivingAWD solenoid
TF-35
Mechanical malfunction of electric con-
trolled coupling (Mechanical engage-
ment of clutch is not possible.)
While driving, AWD warning lamp flashes
rapidly. (When flashing in approx. 1 minute
and then turning OFF.)
Rapid flashing: 2 times/secondWhile drivingProtection function is activated due to
heavy load to electric controlled cou-
pling. (AWD system is not malfunction-
ing. Also, optional distribution of torque
sometimes becomes rigid before lamp
flashes rapidly, but it is not malfunction.)TF-36
While driving, AWD warning lamp flashes
slowly. (When continuing to flash until turn-
ing ignition switch OFF)
Slow flashing: 1 time/2 seconds
While driving

Vehicle speed: 20 km/h
(12 MPH) or moreTire size is different between front and
rear of vehicle.TF-36
Monitored item [Unit] Content Condition Display value
FR RH SENSOR [km/h] or [mph]Wheel speed (Front wheel
right)Vehicle stopped 0.00 km/h (0.00 mph)
Vehicle running
CAUTION:
Check air pressure of tire under
standard condition.Approximately equal to
the indication on speed-
ometer (Inside of ±10%)
FR LH SENSOR [km/h] or [mph]Wheel speed (Front wheel
left)Vehicle stopped 0.00 km/h (0.00 mph)
Vehicle running
CAUTION:
Check air pressure of tire under
standard condition.Approximately equal to
the indication on speed-
ometer (Inside of ±10%)

TF-20
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
*: The values are changed by throttle opening and engine speed.RR RH SENSOR [km/h] or [mph]Wheel speed (Rear wheel
right)Vehicle stopped 0.00 km/h (0.00 mph)
Vehicle running
CAUTION:
Check air pressure of tire under
standard condition.Approximately equal to
the indication on speed-
ometer (Inside of ±10%)
RR LH SENSOR [km/h] or [mph]Wheel speed (Rear wheel
left)Vehicle stopped 0.00 km/h (0.00 mph)
Vehicle running
CAUTION:
Check air pressure of tire under
standard condition.Approximately equal to
the indication on speed-
ometer (Inside of ±10%)
BATTERY VOLT [V]Power supply voltage for
AWD control unitIgnition switch: ON Battery voltage
THRTL POS SEN [%] Throttle opening conditionWhen depressing accelerator pedal
(Value rises gradually in response to
throttle position.)0 - 100%
ETS SOLENOID [A]Monitored value of current at
AWD solenoidEngine running

At idle speedApprox. 0.000A
Engine running

When depressing accelerator
pedalApprox. 0.000 - 2.400A*
STOP LAMP SW [ON/OFF]Condition of brake pedal
operationBrake pedal: Depressed ON
Brake pedal: Released OFF
ENG SPEED SIG [RUN/STOP] Condition of engine runningEngine stopped
(Engine speed: Less than 400 rpm)STOP
Engine running
(Engine speed: 400 rpm or more)RUN
ETS ACTUATOR [ON/OFF]Operating condition of AWD
actuator relay (integrated in
AWD control unit)Engine stopped (Ignition
switch: ON)OFF
Engine running ON
4WD WARN LAMP [ON/OFF] AWD warning lamp conditionAWD warning lamp: ON ON
AWD warning lamp: OFF OFF
4WD MODE MON [AUTO] Control status of AWD Engine running AUTO
DIS-TIRE MONI [mm]Improper size tire installed
conditionVehicle running with normal size tire
installed0-4 mm
Vehicle running with improper size
tire installed (Front/rear tire size dif-
ference, wear condition)4-8 mm, 8- mm
P BRAKE SW [ON/OFF] Condition of parking brakeParking brake operated ON
Parking brake not operated OFF Monitored item [Unit] Content Condition Display value

TROUBLE DIAGNOSIS
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Revision: 2004 November 2004 FX35/FX45
CONSULT-II Function (ALL MODE AWD/4WD)ADS000S5
FUNCTION
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
CONSULT-II SETTING PROCEDURE
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carry out CAN communication.

For details, refer to the separate “CONSULT-II Operations Man-
ual”.
1. Turn ignition switch “OFF”.
2. Connect CONSULT-II and CONSULT-II CONVERTER to data
link connector on vehicle.
3. Turn ignition switch “ON”.
4. Touch “START (NISSAN BASED VHCL)”.
5. Touch “ALL MODE AWD/4WD”.
If “ALL MODE AWD/4WD” is not indicated, go to GI-40, "
CON-
SULT-II Data Link Connector (DLC) Circuit" .
6. Perform each diagnostic test mode according to each service
procedure.
SELF-DIAG RESULT MODE
Operation Procedure
1. Perform “CONSULT-II SETTING PROCEDURE”. Refer to TF-21, "CONSULT-II SETTING PROCEDURE"
.
2. Start engine and drive at 30 km/h (19 MPH) or more for approx. 1 minute.
Diagnostic test mode FunctionReference
page
Self-diagnostic results

Self-diagnostic results can be read and erased quickly.TF-21
Data monitor
Input/Output data in the AWD control unit can be read.TF-23
CAN diagnostic support monitor
The results of transmit/receive diagnosis of CAN communication can be read. —
Active test

Diagnostic Test Mode in which CONSULT-II drives some actuators apart from
the AWD control unit and also shifts some parameters in a specified range.TF-24
ECU part number
AWD control unit part number can be read.TF-24
PBIB1503E
SAIA0450E
SDIA2216E