Throttle INFINITI FX35 2006 Service Manual

ACS-6
[ICC]
DESCRIPTION
Revision: 2006 December 2006 FX35/FX45
DESCRIPTIONPFP:00000
OutlineNKS003EJ
The Intelligent Cruise Control (ICC) system automatically maintains a selected distance from the vehicle
ahead according to that vehicle's speed, or at the set speed, if the road ahead is clear.
The ICC function has two cruise control modes and brake assist (with preview function).
VEHICLE-TO-VEHICLE DISTANCE CONTROL MODE
With vehicle-to-vehicle distance control mode, the driver can maintain the same speed as other vehicles with-
out the constant need to adjust the set speed as the driver would with a normal cruise control system.
The system is intended to enhance the operation of the vehicle when following the vehicle traveling in the
same lane and direction.
If the distance sensor detects a slower moving vehicle ahead, the system will reduce speed so that the vehicle
ahead can be followed at the selected distance.
The system automatically controls the throttle and applies the brakes (up to 25% of vehicle braking power) if
necessary.
The detection range of the sensor is approximately 120 m (390 ft) ahead.
Refer to Owner's Manual for Intelligent Cruise Control System operating instructions.
CONVENTIONAL (FIXED SPEED) CRUISE CONTROL MODE
Conventional (fixed speed) cruise control mode is cruising at preset speeds.
Refer to Owner's Manual for Intelligent Cruise Control System operating instructions.
BRAKE ASSIST (WITH PREVIEW FUNCTION)
When the force applied to brake pedal exceeds a certain level, the Brake Assist is activated and generates a
greater braking force than that of a conventional brake booster even with light pedal force.
When the Preview Function identifies the need to apply the sudden brake by sensing the vehicle ahead in the
same lane and the distance and relative speed from it, it applies the brake pre-pressure before driver depress
the brake pedal and improves brake response by reducing its free play.
Refer to Owner's Manual for BRAKE ASSIST (WITH PREVIEW FUNCTION) operating instructions.

DESCRIPTION ACS-7
[ICC]
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Revision: 2006 December 2006 FX35/FX45
Functional DiagramNKS003ID
Items of input/output signal to be checked with CONSULT-II
PKIC8700E
Input Data monitored
Item [unit] CAN Description
ECM THRTL OPENING
[%] ×Indicates throttle angle read by ICC unit through CAN communication (ECM transmits
throttle angle through CAN communication).
ENGINE RPM
[rpm] ×
Indicates engine speed read by ICC unit through CAN communication (ECM transmits
engine speed through CAN communication).
MAIN SW
[ON/OFF] × Indicates [ON/OFF] status as judged from steering switch signal (ECM transmits steer-
ing switch signal through CAN communication).
SET/COAST SW
[ON/OFF] ×Indicates [ON/OFF] status as judged from steering switch signal (ECM transmits steer-
ing switch signal through CAN communication).
CANCEL SW
[ON/OFF] ×
Indicates [ON/OFF] status as judged from steering switch signal (ECM transmits steer-
ing switch signal through CAN communication).
RESUME/ACC SW
[ON/OFF] × Indicates [ON/OFF] status as judged from steering switch signal (ECM transmits steer-
ing switch signal through CAN communication).
IDLE SW
[ON/OFF] ×Indicates [ON/OFF] status of idle switch read by ICC unit through CAN communication
(ECM transmits ON/OFF status through CAN communication).
TCM VHCL SPD AT
[km/h] or [mph] × Indicates vehicle speed calculated from AT vehicle speed sensor by ICC unit through
CAN communication (TCM transmits AT vehicle speed sensor signal through CAN com-
munication).
GEAR
[1, 2, 3, 4, 5] ×
Indicates AT gear position read by ICC unit through CAN communication (TCM trans-
mits gear position through CAN communication).
D RANGE SW
[ON/OFF] × Indicates [ON/OFF] status of “D” position read by ICC unit through CAN communication
(TCM transmits ON/OFF condition of “D” position through CAN communication).
NP RANGE SW
[ON/OFF] ×Indicates PNP switch signal read by ICC unit through CAN communication (TCM trans-
mits PNP switch signal through CAN communication).

DESCRIPTION ACS-9
[ICC]
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Revision: 2006 December 2006 FX35/FX45
Components DescriptionNKS003EL
CAN CommunicationNKS003EM
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-
tric 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.
CAN COMMUNICATION UNIT
Refer to LAN-32, "CAN Communication Unit" .
Component Vehicle-to-
vehicle
distance
control mode Conventional
(fixed speed) cruise
control mode Brake assist
(with pre-
view func- tion) Description
ICC unit ××× Operates electric throttle control actuator and brake
booster based on that sensor signals and CAN commu-
nication data, then controls vehicle distance.
ICC sensor ×× Irradiates laser beam, and receives reflected laser
beam to measure distance from preceding vehicle.
ECM ××× Transmits throttle position signal and ICC steering
switch signal to ICC unit through CAN communication.
ABS actuator and electric
unit (control unit) ×××
Transmits wheel speed sensor signal to ICC unit
through CAN communication.
Brake pressure sensor ×× Detects fluid pressure in master cylinder.
Brake booster ×× Adjusts brake fluid pressure, based on command from
ICC unit.
BCM × Transmit front wiper request signal to ICC unit through
CAN communication.
TCM ×× Transmits gear position signal and output shaft revolu-
tion signal to ICC unit through CAN communication.
Unified meter and A/C amp. ××× Receives ICC system display signal, ICC warning lamp
signal and buzzer output signal from ICC unit through
CAN communication.
ICC brake switch, stop
lamp switch ××× Transmit operating signal to ICC unit when touching
brake pedal. ICC unit cancels cruise system at driver's
brake operation.
ICC brake hold relay × Receives stop lamp driving signal from ICC unit, and
turns stop lamp ON.
Parking brake switch ×× The cruise system is cancelled when applied.

TROUBLE DIAGNOSIS — GENERAL DESCRIPTION ACS-33
[ICC]
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Revision: 2006 December 2006 FX35/FX45
DATA MONITOR
Operation Procedure
1. Touch “DATA MONITOR” on “SELECT DIAG MODE” screen. Refer to GI-38, "
CONSULT-II Start Procedure" .
2. Touch any of “ECU INPUT SIGNALS”, “MAIN SIGNALS” and “SELECTION FROM MENU” on selection screen.
3. Touch “START”.
4. Display the data monitor.
5. If necessary, touch “COPY” in turn, and print data.
Monitored Item
× : Applicable
PKIB0112E
Monitored Item
[unit] ECU INPUT
SIGNALS MAIN
SIGNALS SELEC-
TION FROM MENU Description
VHCL SPEED SE
[km/h] or [mph] ××× Indicates vehicle speed calculated from ICC unit through CAN
communication [ABS actuator and electric unit (control unit)
transmits wheel speed sensor signal through CAN communica-
tion].
SET VHCL SPD
[km/h] or [mph] ××Indicates set vehicle speed memorized in ICC unit.
THRTL OPENING
[%] ××× Indicates throttle angle read from ICC unit through CAN commu-
nication (ECM transmits throttle angle through CAN communi-
cation).
ENGINE RPM
[rpm] ×× Indicates engine speed read from ICC unit through CAN com-
munication (ECM transmits engine speed through CAN commu-
nication).
DISTANCE ADJ
[SHOR/MID/LONG] ××× Indicates set distance memorized in ICC unit.
WIPER SW
[OFF/LOW/HIGH] ×× Indicates wiper [OFF/LOW/HIGH] status (BCM transmits front
wiper request signal through CAN communication).
MAIN SW
[ON/OFF] ××× Indicates [ON/OFF] status as judged from ICC steering switch
signal (ECM transmits ICC steering switch signal through CAN
communication).
SET/COAST SW
[ON/OFF] ××× Indicates [ON/OFF] status as judged from ICC steering switch
signal (ECM transmits ICC steering switch signal through CAN
communication).
CANCEL SW
[ON/OFF] ××× Indicates [ON/OFF] status as judged from ICC steering switch
signal (ECM transmits ICC steering switch signal through CAN
communication).
RESUME/ACC SW
[ON/OFF] ××× Indicates [ON/OFF] status as judged from ICC steering switch
signal (ECM transmits ICC steering switch signal through CAN
communication).
CRUISE OPE
[ON/OFF] ××
Indicates whether controlling or not (ON means “controlling”).
BRAKE SW
[ON/OFF] ××× Indicates [ON/OFF] status as judged from ICC brake switch sig-
nal.
STOP LAMP SW
[ON/OFF] ××× Indicates [ON/OFF] status as judged from stop lamp switch sig-
nal.
RELEASE SW NO
[ON/OFF] ×× Indicates [ON/OFF] status as judged from release switch signal.
ON when brake is depressed.
OFF when brake is not depressed.

AT-2Revision: 2006 December 2006 FX35/FX45 On Board Diagnosis Logic ...................................
.112
Possible Cause .................................................... .112
DTC Confirmation Procedure .............................. .112
Wiring Diagram — AT — PNP/SW ...................... .113
Diagnostic Procedure .......................................... .114
DTC P0717 TURBINE REVOLUTION SENSOR ... .116
Description ........................................................... .116
CONSULT-II Reference Value ............................. .116
On Board Diagnosis Logic ................................... .116
Possible Cause .................................................... .116
DTC Confirmation Procedure .............................. .116
Diagnostic Procedure .......................................... .117
DTC P0720 VEHICLE SPEED SENSOR A/T (REV-
OLUTION SENSOR) .............................................. .118
Description ........................................................... .118
CONSULT-II Reference Value ............................. .118
On Board Diagnosis Logic ................................... .118
Possible Cause .................................................... .118
DTC Confirmation Procedure .............................. .118
Wiring Diagram — AT — VSSA/T ........................ .120
Diagnostic Procedure .......................................... .121
DTC P0725 ENGINE SPEED SIGNAL .................. .123
Description ........................................................... .123
CONSULT-II Reference Value ............................. .123
On Board Diagnosis Logic ................................... .123
Possible Cause .................................................... .123
DTC Confirmation Procedure .............................. .123
Diagnostic Procedure .......................................... .124
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE ................................................ .125
Description ........................................................... .125
CONSULT-II Reference Value ............................. .125
On Board Diagnosis Logic ................................... .125
Possible Cause .................................................... .125
DTC Confirmation Procedure .............................. .125
Diagnostic Procedure .......................................... .126
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP) .127
Description ........................................................... .127
CONSULT-II Reference Value ............................. .127
On Board Diagnosis Logic ................................... .127
Possible Cause .................................................... .127
DTC Confirmation Procedure .............................. .127
Diagnostic Procedure .......................................... .128
DTC P0745 LINE PRESSURE SOLENOID VALVE .129
Description ........................................................... .129
CONSULT-II Reference Value ............................. .129
On Board Diagnosis Logic ................................... .129
Possible Cause .................................................... .129
DTC Confirmation Procedure .............................. .129
Diagnostic Procedure .......................................... .130
DTC P1705 THROTTLE POSITION SENSOR ...... .131
Description ........................................................... .131
CONSULT-II Reference Value ............................. .131
On Board Diagnosis Logic ................................... .131
Possible Cause .................................................... .131
DTC Confirmation Procedure .............................. .131
Diagnostic Procedure .......................................... .132
DTC P1710 A/T FLUID TEMPERATURE SENSOR
CIRCUIT ................................................................. .134 Description ...........................................................
.134
CONSULT-II Reference Value .............................. .134
On Board Diagnosis Logic ................................... .134
Possible Cause .................................................... .134
DTC Confirmation Procedure ............................... .134
Wiring Diagram — AT — FTS .............................. .135
Diagnostic Procedure ........................................... .136
Component Inspection ......................................... .138
DTC P1721 VEHICLE SPEED SENSOR MTR ...... .139
Description ........................................................... .139
CONSULT-II Reference Value .............................. .139
On Board Diagnosis Logic ................................... .139
Possible Cause .................................................... .139
DTC Confirmation Procedure ............................... .139
Diagnostic Procedure ........................................... .140
DTC P1730 A/T INTERLOCK ................................ .141
Description ........................................................... .141
On Board Diagnosis Logic ................................... .141
Possible Cause .................................................... .141
DTC Confirmation Procedure ............................... .141
Judgement of A/T Interlock .................................. .141
Diagnostic Procedure ........................................... .142
DTC P1731 A/T 1ST ENGINE BRAKING .............. .144
Description ........................................................... .144
CONSULT-II Reference Value .............................. .144
On Board Diagnosis Logic ................................... .144
Possible Cause .................................................... .144
DTC Confirmation Procedure ............................... .144
Diagnostic Procedure ........................................... .145
DTC P1752 INPUT CLUTCH SOLENOID VALVE . .146
Description ........................................................... .146
CONSULT-II Reference Value .............................. .146
On Board Diagnosis Logic ................................... .146
Possible Cause .................................................... .146
DTC Confirmation Procedure ............................... .146
Diagnostic Procedure ........................................... .147
DTC P1754 INPUT CLUTCH SOLENOID VALVE
FUNCTION ............................................................. .148
Description ........................................................... .148
CONSULT-II Reference Value .............................. .148
On Board Diagnosis Logic ................................... .148
Possible Cause .................................................... .148
DTC Confirmation Procedure ............................... .148
Diagnostic Procedure ........................................... .149
DTC P1757 FRONT BRAKE SOLENOID VALVE .. .150
Description ........................................................... .150
CONSULT-II Reference Value .............................. .150
On Board Diagnosis Logic ................................... .150
Possible Cause .................................................... .150
DTC Confirmation Procedure ............................... .150
Diagnostic Procedure ........................................... .151
DTC P1759 FRONT BRAKE SOLENOID VALVE
FUNCTION ............................................................. .152
Description ........................................................... .152
CONSULT-II Reference Value .............................. .152
On Board Diagnosis Logic ................................... .152
Possible Cause .................................................... .152
DTC Confirmation Procedure ............................... .152
Diagnostic Procedure ........................................... .153

AT-3
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Revision: 2006 December 2006 FX35/FX45 DTC P1762 DIRECT CLUTCH SOLENOID VALVE
. 154
Description .......................................................... . 154
CONSULT-II Reference Value ............................. . 154
On Board Diagnosis Logic .................................. . 154
Possible Cause ................................................... . 154
DTC Confirmation Procedure .............................. . 154
Diagnostic Procedure .......................................... . 155
DTC P1764 DIRECT CLUTCH SOLENOID VALVE
FUNCTION ............................................................. . 156
Description .......................................................... . 156
CONSULT-II Reference Value ............................. . 156
On Board Diagnosis Logic .................................. . 156
Possible Cause ................................................... . 156
DTC Confirmation Procedure .............................. . 156
Diagnostic Procedure .......................................... . 157
DTC P1767 HIGH AND LOW REVERSE CLUTCH
SOLENOID VALVE ................................................ . 158
Description .......................................................... . 158
CONSULT-II Reference Value ............................. . 158
On Board Diagnosis Logic .................................. . 158
Possible Cause ................................................... . 158
DTC Confirmation Procedure .............................. . 158
Diagnostic Procedure .......................................... . 159
DTC P1769 HIGH AND LOW REVERSE CLUTCH
SOLENOID VALVE FUNCTION ............................ . 160
Description .......................................................... . 160
CONSULT-II Reference Value ............................. . 160
On Board Diagnosis Logic .................................. . 160
Possible Cause ................................................... . 160
DTC Confirmation Procedure .............................. . 160
Diagnostic Procedure .......................................... . 161
DTC P1772 LOW COAST BRAKE SOLENOID
VALVE .................................................................... . 162
Description .......................................................... . 162
CONSULT-II Reference Value ............................. . 162
On Board Diagnosis Logic .................................. . 162
Possible Cause ................................................... . 162
DTC Confirmation Procedure .............................. . 162
Diagnostic Procedure .......................................... . 163
DTC P1774 LOW COAST BRAKE SOLENOID
VALVE FUNCTION ................................................ . 164
Description .......................................................... . 164
CONSULT-II Reference Value ............................. . 164
On Board Diagnosis Logic .................................. . 164
Possible Cause ................................................... . 164
DTC Confirmation Procedure .............................. . 164
Diagnostic Procedure .......................................... . 165
DTC P1815 MANUAL MODE SWITCH ................. . 166
Description .......................................................... . 166
CONSULT-II Reference Value in Data Monitor Mode . 166
On Board Diagnosis Logic .................................. . 166
Possible Cause ................................................... . 166
DTC Confirmation Procedure .............................. . 166
Wiring Diagram — AT — MMSW ........................ . 167
Diagnostic Procedure .......................................... . 169
Component Inspection ........................................ . 170
DTC P1841 ATF PRESSURE SWITCH 1 .............. . 171
Description .......................................................... . 171 CONSULT-II Reference Value .............................
.171
On Board Diagnosis Logic ................................... .171
Possible Cause .................................................... .171
DTC Confirmation Procedure .............................. .171
Diagnostic Procedure .......................................... .172
DTC P1843 ATF PRESSURE SWITCH 3 .............. .173
Description ........................................................... .173
CONSULT-II Reference Value ............................. .173
On Board Diagnosis Logic ................................... .173
Possible Cause .................................................... .173
DTC Confirmation Procedure .............................. .173
Diagnostic Procedure .......................................... .174
DTC P1845 ATF PRESSURE SWITCH 5 .............. .175
Description ........................................................... .175
CONSULT-II Reference Value ............................. .175
On Board Diagnosis Logic ................................... .175
Possible Cause .................................................... .175
DTC Confirmation Procedure .............................. .175
Diagnostic Procedure .......................................... .176
DTC P1846 ATF PRESSURE SWITCH 6 .............. .177
Description ........................................................... .177
CONSULT-II Reference Value ............................. .177
On Board Diagnosis Logic ................................... .177
Possible Cause .................................................... .177
DTC Confirmation Procedure .............................. .177
Diagnostic Procedure .......................................... .178
MAIN POWER SUPPLY AND GROUND CIRCUIT .179
Wiring Diagram — AT — MAIN ........................... .179
Diagnostic Procedure .......................................... .180
CLOSED THROTTLE POSITION AND WIDE OPEN
THROTTLE POSITION CIRCUIT ........................... .183
CONSULT-II Reference Value ............................. .183
Diagnostic Procedure .......................................... .183
BRAKE SIGNAL CIRCUIT ..................................... .184
CONSULT-II Reference Value ............................. .184
Diagnostic Procedure .......................................... .184
A/T INDICATOR CIRCUIT ...................................... .185
Description ........................................................... .185
CONSULT-II Reference Value ............................. .185
Diagnostic Procedure .......................................... .185
TROUBLE DIAGNOSIS FOR SYMPTOMS ........... .186
Wiring Diagram — AT — NONDTC ..................... .186
A/T CHECK Indicator Lamp Does Not Come On . 189
Engine Cannot Be Started in “P” or “N” Position . .190
In “P” Position, Vehicle Moves When Pushed ..... .191
In “N” Position, Vehicle Moves ............................. .192
Large Shock (“N” to “D” Position) ........................ .193
Vehicle Does Not Creep Backward in “R” Position .196
Vehicle Does Not Creep Forward in “D” Position . 199
Vehicle Cannot Be Started From D
1 .................... .201
A/T Does Not Shift: D
1 → D2 ............................... .204
A/T Does Not Shift: D
2 → D3 ............................... .206
A/T Does Not Shift: D
3 → D4 ............................... .208
A/T Does Not Shift: D
4 → D5 ............................... .211
A/T Does Not Lock-up ......................................... .213
A/T Does Not Hold Lock-up Condition ................. .215
Lock-up Is Not Released ..................................... .217
Engine Speed Does Not Return to Idle ............... .217
Cannot Be Changed to Manual Mode ................. .219

AT-32
A/T CONTROL SYSTEM
Revision: 2006 December 2006 FX35/FX45
TCM FunctionNCS001AZ
The function of the TCM is to:

Receive input signals sent from various switches and sensors.

Determine required line pressure, shifting point, lock-up operation, and engine brake operation.

Send required output signals to the respective solenoids.
CONTROL SYSTEM OUTLINE
The automatic transmission senses vehicle operating conditions through various sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
CONTROL SYSTEM DIAGRAM
SENSORS (or SIGNALS)

TCM

ACTUATORS
PNP switch
Accelerator pedal position signal
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Vehicle speed signal
Manual mode switch signal
Stop lamp switch signal
Turbine revolution sensor
ATF pressure switch Shift control
Line pressure control
Lock-up control
Engine brake control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
Duet-EA control
CAN system Input clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch
solenoid valve
Low coast brake solenoid valve
Torque converter clutch solenoid
valve
Line pressure solenoid valve
A/T CHECK indicator lamp
Starter relay
Back-up lamp relay
SCIA5325E

A/T CONTROL SYSTEM AT-33
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Revision: 2006 December 2006 FX35/FX45
CAN CommunicationNCS001B0
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-32,
"CAN Communication Unit" .
Input/Output Signal of TCMNCS001B1
*1: Spare for vehicle speed sensor·A/T (revolution sensor)
*2: Spare for accelerator pedal position signal
*3: If these input and output signals are different, the TCM triggers the fail-safe function.
*4: Used as a condition for starting self-diagnostics; if self-diagnostics are not started, it is judged that there is some kin d of error.
*5: Input by CAN communications
*6: Output by CAN communications Control item
Line
pressure control Vehicle
speed
control Shift
control Lock-up
control Engine
brake
control Fail-safe
function (*3) Self-diag-
nostics
function
Input Accelerator pedal position signal
(*5)XXXXXXX
Vehicle speed sensor A/T
(revolution sensor) XXXXXXX
Vehicle speed sensor MTR
(*1) (*5)X
Closed throttle position signal
(*5)X (*2) X X X X (*4)
Wide open throttle position signal
(*5)XX (*4)
Turbine revolution sensor 1 X X X X X
Turbine revolution sensor 2
(for 4th speed only) X XXXX
Engine speed signals
(*5)XXXXXXX
Stop lamp switch signal
(*5)XXX X (*4)
A/T fluid temperature sensors 1, 2XXXX XX
ASCD or
ICC Operation signal
(*5)XXX
Overdrive cancel
signal
(*5)X
Out-
put Direct clutch solenoid (ATF pres-
sure switch 5) XX XX
Input clutch solenoid (ATF pressure
switch 3) XX XX
High and low reverse clutch sole-
noid (ATF pressure switch 6) XX XX
Front brake solenoid (ATF pressure
switch 1) XX XX
Low coast brake solenoid (ATF
pressure switch 2) XX XXX
Line pressure solenoid XXXXXXX
TCC solenoid X X X
Self-diagnostics table
(*6)X
Sta rter rela y XX

AT-44
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
TROUBLE DIAGNOSISPFP:00004
DTC Inspection Priority ChartNCS001BC
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
If DTC U1000 is displayed with other DTCs, first perform the trouble diagnosis for DTC U1000 CAN
COMMUNICATION. Refer to AT- 1 0 4
.
Fail-safeNCS001BD
The TCM has an electrical fail-safe mode. This mode makes it possible to operate even if there is a an error in
a main electronic control input/output signal circuit.
In fail-safe mode, even if the selector lever is “D” or “M” mode, the transmission is fixed in 2nd, 4th or 5th
(depending on the breakdown position), so the customer should feel “slipping” or “poor acceleration”.
Even when the electronic circuits are normal, under special conditions (for example, when slamming on the
brake with the wheels spinning drastically and stopping the tire rotation), the transmission can go into fail-safe
mode. If this happens, switch OFF the ignition switch for 10 seconds, then switch it ON again to return to the
normal shift pattern. Therefore, the customer's vehicle has returned to normal, so handle according to the
“WORK FLOW” (Refer to AT- 4 7
).
FAIL-SAFE FUNCTION
If any malfunction occurs in a sensor or solenoid, this function controls the A/T to mark driving possible.
Vehicle Speed Sensor
Signals are input from two systems - from vehicle speed sensor A/T (revolution sensor) installed on the trans-
mission and from combination meter so normal driving is possible even if there is a malfunction in one of the
systems. And if vehicle speed sensor A/T (revolution sensor) has unusual cases, 5th gear and manual mode
are prohibited.
Accelerator Pedal Position Sensor
If there is a malfunction in one of the systems, the accelerator opening angle is controlled by ECM according
to a pre-determined accelerator angle to make driving possible. And if there are malfunctions in tow systems,
the engine speed is fixed by ECM to a pre-determined engine speed to make driving possible.
Throttle Position Sensor
If there is a malfunction in one of the systems, the accelerator opening angle is controlled by ECM according
to a pre-determined accelerator angle to make driving possible. And if there are malfunctions in tow systems,
the accelerator opening angle is controlled by the idle signal sent from the ECM which is based on input indi-
cating either idle condition or off-idle condition (pre-determined accelerator opening) in order to make driving
possible.
PNP Switch
In the unlikely event that a malfunction signal enters the TCM, the position indicator is switched OFF, the
starter relay is switched OFF (starter starting is disabled), the back-up lamp relay switched OFF (back-up lamp
is OFF) and the position is fixed to the “D” position to make driving possible.
Starter Relay
The starter relay is switched OFF. (Starter starting is disabled.)
Priority Detected items (DTC)
1 U1000 CAN communication line
2 Except above

AT-46
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
How to Perform Trouble Diagnosis for Quick and Accurate RepairNCS001BE
INTRODUCTION
The TCM receives a signal from the vehicle speed sensor, accelerator pedal position sensor (throttle position
sensor) or PNP switch and provides shift control or lock-up control via A/T solenoid valves.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used with the OBD-related parts of the
A/T system for malfunction-diagnostic purposes. The TCM is capa-
ble of diagnosing malfunctioning parts while the ECM can store mal-
functions in its memory.
Input and output signals must always be correct and stable in the
operation of the A/T system. The A/T system must be in good oper-
ating condition and be free of valve seizure, solenoid valve malfunc-
tion, etc.
It is much more difficult to diagnose a error that occurs intermittently
rather than continuously. Most intermittent errors are caused by poor
electric connections or improper wiring. In this case, careful check-
ing of suspected circuits may help prevent the replacement of good
parts.
A visual check only may not find the cause of the errors. A road test
with CONSULT-II (or GST) or a circuit tester connected should be
performed. Follow the AT- 4 7 , "
WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such errors, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “DIAGNOSTIC WORKSHEET” as
shown on the example (Refer to AT- 4 8
) should be used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot driveability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
SAT631IB
SAT632I
SEF234G