traction control INFINITI FX35 2007 Service Manual

BRC-8
[VDC/TCS/ABS]
SYSTEM DESCRIPTION
Revision: 2006 July 2007 FX35/FX45
SYSTEM DESCRIPTIONPFP:00000
System DiagramNFS000N3
FunctionsNFS000N4
VDC

In addition to the TCS/ABS function, the driver steering amount and brake operation amount are detected
from steering angle sensor and pressure sensor, and the vehicle's driving status (amount of under steer-
ing / over steering) is determined from information from G sensor, wheel sensor, etc., and this information
is used to improve vehicle stability by controlling the braking and engine power to all four wheels.

SLIP indicator lamp flashes to inform the driver of VDC operation.

During VDC operation, body and brake pedal lightly vibrate and mechanical noises may be heard. This is
normal.

ABS warning lamp, VDC OFF indicator lamp, and SLIP indicator lamp might turn on when vehicle is sub-
ject to strong shaking or large vibration, such as when vehicle is on a turn table, a ship or a steep slope
such as bank while engine is running. In this case, restart engine on a normal road, and if ABS warning
lamp, VDC OFF indicator lamp, and SLIP indicator lamp turn off, there is no malfunction.
TCS

The wheel spin of the drive wheels is detected by ABS actuator and electric unit (control unit) from the
wheel speed signals from four wheels, so if wheel spin occurs, drive wheel right and left brake fluid pres-
sure control and engine fuel cut are performed while throttle value is restricted to reduce the engine
torque and decrease the amount of wheel spin. In addition, the degree throttle is opened is controlled to
achieve the optimum engine torque.

Depending on road circumstances, the driver may have a sluggish feel. This is normal, because the opti-
mum traction has the highest priority under TCS operation.

TCS may be activated any time vehicle suddenly accelerates, suddenly down/upshifts, or is driven on a
road with a varying surface friction coefficient.

During TCS operation, it informs a driver of system operation by flashing SLIP indicator lamp.
SFIA1160E

TROUBLE DIAGNOSIS BRC-33
[VDC/TCS/ABS]
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BRC
Revision: 2006 July 2007 FX35/FX45
For Fast and Accurate DiagnosisNFS000NH
PRECAUTIONS FOR DIAGNOSIS

Before performing diagnosis, always read precautions. Refer to BRC-11, "How to Proceed with Diagnosis"
.

If ABS actuator and electric unit (control unit), steering angle sensor, steering system parts or suspension
system parts have been replaced, or if alignment has been adjusted, be sure to adjust neutral position of
steering angle sensor before driving. Refer to BRC-6, "
Adjustment of Steering Angle Sensor Neutral Posi-
tion" .

After diagnosis is finished, be sure to erase memory. Refer to BRC-25, "Self-Diagnosis" .

When checking continuity and voltage between units, be sure to check for disconnection, looseness,
bend, or collapse of connector terminals. If any malfunction is found, repair or replace connector termi-
nals.

For intermittent symptoms, possible cause is malfunction in harness, harness connector, or terminals.
Move harness, harness connector, and terminals to check for poor connections.

If a circuit tester is used for the check, be careful not to forcibly extend any connector terminal.

To use CONSULT-II to perform self-diagnosis of ABS actuator and electric unit (control unit), active tests,
or work support, first stop work, then connect CONSULT-II and select “ABS”.

While self-diagnostic results of CONSULT-II shows malfunction, if CONSULT-II active test is performed,
an engine system error may be indicated. In this case, start engine to resume the normal screen.

VDC/TCS/ABS system electronically controls brake operation and engine output. The following symptoms
may be caused by normal operations:
Symptom Symptom description Result
Motor operation noise This is noise of motor inside ABS actuator and electric unit (control unit).
Slight noise may occur during VDC, TCS, and ABS operation.
Normal
When the vehicle speed goes over 20 km/h (12.5 MPH), motor and valves
operating noise may be heard. It happens only once after ignition switch is
ON. This is a normal status of the system operation check.
System operation check noise When engine starts, slight “click” noise may be heard from engine room.
This is normal and is part of system operation check. Normal
VDC/TCS operation
(SLIP indicator lamp blinking) TCS may activate momentarily if wheel speed changes when driving over
location where friction coefficient varies, when up/downshifting, or when
fully depressing accelerator pedal.
Normal
Cancel the VDC/TCS
function for the inspec-
tion on a chassis dyna-
mometer.
For inspection of speedometer or other instruments, press VDC OFF
switch to turn VDC/TCS function off.
When accelerator pedal is depressed on a chassis dynamometer (fixed
front-wheel type), vehicle speed will not increase. This is not normal. It is
result of TCS being activated by stationary front wheels. Warning lamp may
also illuminate to indicate “sensor system error”. This is also normal, and is
the result of the stationary front wheels being detected. To be certain,
restart engine, and drive vehicle at 30 km/h (19 MPH) or more. Make sure
warning lamp does not illuminate.
ABS operation
(Longer stopping distance) On roads with low friction coefficients, such as snowy roads or gravel
roads, vehicles with ABS may require a longer stopping distance. There-
fore, when driving on such roads, avoid overconfidence and keep speed
sufficiently low. Normal
Insufficient feeling of acceler-
ation Depending on road conditions, driver may feel that feeling of acceleration
is insufficient. This is because traction control, which controls engine and
brakes to achieve optimal traction, has the highest priority (for safety). As a
result, there may be times when acceleration is slightly less than usual for
the same accelerator pedal operation. Normal

IDX-7
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ALPHABETICAL INDEX
Refrigeration cycle ...........................................
ATC-21
Removal and installation (A/T) ........... AT-266, AT-269
Removal and installation (Transfer) .................... TF-44
Revolution sensor (A/T) ...................... AT-118, AT-259
Rocker cover(VK45DE) ................................... EM-200
Rocker cover(VQ35DE) ..................................... EM-51
RP/SEN - Wiring diagram ................ EC-664, EC-1346
S
SAE J1979 - Service $01 - 09 ........... EC-129
, EC-715
Seal - See Exterior .............................................. EI-27
Seat belt inspection ............................................. SB-7
Seat belt, front ..................................................... SB-4
Seat, rear ......................................................... SE-104
Self-diagnosis (Transfer) .................................... TF-22
Self-diagnostic results ....................................... EC-70
SEN/PW - Wiring diagram ............... EC-484, EC-1152
SHIFT - Wiring diagram ................................... AT-233
Shift lock system .............................................. AT-232
Shift schedule .................................................. AT-359
Shock absorber (rear) ....................................... RSU-9
Side air bag (satellite) sensor .......................... SRS-51
Side curtain air bag .......................................... SRS-48
Side trim .............................................................. EI-38
SMJ (super multiple junction) ............................ PG-76
SNOW MODE SW ........................... EC-668, EC-1350
SNOWSW - Wiring diagram ............ EC-669, EC-1351
Spark plug replacement ..................................... MA-27
Spark plug replacement(VQ35DE) .................... MA-20
Spark plug(VK45DE) ....................................... EM-192
Spark plug(VQ35DE) ......................................... EM-43
Specification value ............................. EC-137, EC-802
Speedometer ........................................................ DI-5
Spiral cable ...................................................... SRS-44
SROOF - Wiring diagram ..................... BL-166, RF-13
SRS - See Supplemental Restraint System ...... SRS-5
SRS - Wiring diagram ...................................... SRS-12
SRS Trouble diagnoses ..................................... SRS-8
Stabilizer bar (rear) ......................................... RSU-16
Stall test (A/T) .................................................... AT-53
Standardized relay ............................................. PG-78
START - Wiring diagram ................................... SC-12
Starter ................................................................ SC-11
Starting system .................................................. SC-11
Steering gear and linkage inspection ................ MA-36
Steering linkage ................................................. PS-18
Steering wheel and column ................... PS-10, PS-13
Stop lamp switch ............................. EC-552, EC-1233
STSIG - Wiring diagram .................................. AT-108
Sun roof, electric ................................................ RF-10
Sunload sensor ............................. ATC-109, ATC-118
Sunroof .................................................. RF-10, RF-23
Supplemental Restraint System ........................ SRS-5
Supplemental restraint system - Wiring diagram ..........
SRS-12
Suspension ........................................................ MA-37
Symbols and abbreviations ..................... GI-11, GI-24
Symptom matrix chart ........................................ EC-96
System readiness test (SRT) code ...... EC-59, EC-721
T
Tachometer ........................................................... DI-5
TCM circuit diagram ........................................... AT-52
TCM inspection table ......................................... AT-89
Thermostat(VK45DE) ....................................... CO-53
Thermostat(VQ35DE) ....................................... CO-27
Three way catalyst function (Bank 1) EC-376, EC-1045
Three way catalyst function (Bank 2) EC-376, EC-1045
Three way catalyst precautions ............................ GI-6
Three way catalyst(VK45DE) .......................... EM-183
Three way catalyst(VQ35DE) ........................... EM-26
Throttle control motor ....................... EC-569, EC-1251
Throttle control motor relay .............. EC-557, EC-1238
Throttle position sensor (TPS) .......... EC-214, EC-338,
EC-509
, EC-511, EC-590, EC-886, EC-1009, EC-1185,
EC-1187
, EC-1272
Throttle valve closed position learning . EC-83, EC-745
Tie-rod ............................................................... PS-18
Timing chain(VK45DE) ................................... EM-203
Timing chain(VQ35DE) ..................................... EM-64
Tire rotation ....................................................... MA-35
Top tether strap child restraint ........................... SB-11
Torque converter installation AT-267, AT-268, AT-272
Torque convertor clutch solenoid valve AT-125, AT-127
TPS1 - Wiring diagram .................... EC-340, EC-1011
TPS2 - Wiring diagram ...................... EC-216, EC-888
TPS3 - Wiring diagram .................... EC-592, EC-1274
Traction control system circuit (engine) .......... EC-494,
EC-495
Transfer control unit inspection table ................. TF-21
Transverse link (front) ...................................... FSU-14
TRNSCV - Wiring diagram ............................... BL-226
Trouble diagnoses .............................................. GI-12
Two trip detection logic ........................ EC-53, EC-715
Tyre pressure monitoring system - trouble diagnoses ..
WT-15
Tyre pressure monitoring system - wiring diagram .......
WT-16
U
Unified meter and A/C amp. ............................... DI-28
V
Vacuum hose (brake system) ............................ BR-17
Vacuum hose drawing (Engine control) ........... EC-106
Valve clearance(VK45DE) .............................. EM-222
Valve clearance(VQ35DE) ................................ EM-93
Valve guide ..................................................... EM-108
Valve guide(VK45DE) ..................................... EM-239
Valve lifter ......................................................... EM-87
Valve seat(VK45DE) ....................................... EM-241
Valve seat(VQ35DE) ...................................... EM-110
Valve spring(VK45DE) .................................... EM-242
Valve spring(VQ35DE) ................................... EM-111