ACS-6
[ICC]
DESCRIPTION
Revision: 2004 November 2004 FX35/FX45
DESCRIPTIONPFP:00000
OutlineAKS006YB
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
Vehicle-to-vehicle distance control mode, the same speed as other vehicles can be maintained without the
constant need to adjust the operating speed as with a normal cruise control system.
The system is intended to enhance the operation of the vehicle when following another vehicle 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 390 ft (120 m) 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.
System DiagramAKS006YC
SKIA5972E
PRECAUTIONS
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Revision: 2004 November 2004 FX35/FX45
Service Notice or PrecautionsACS002L7
ATF COOLER SERVICE
If A/T fluid contains frictional material (clutches, bands, etc.), or if an A/T is repaired, overhauled, or replaced,
inspect and clean the A/T fluid cooler mounted in the radiator or replace the radiator. Flush cooler lines using
cleaning solvent and compressed air after repair. For A/T fluid cooler cleaning procedure, refer to AT- 1 4 , "
A/T
Fluid Cooler Cleaning" . For radiator replacement, refer to CO-14, "RADIATOR" (for VQ35DE) or CO-39,
"RADIATOR" (for VK45DE).
OBD-II SELF-DIAGNOSIS
A/T self-diagnosis is performed by the TCM in combination with the ECM. The results can be read through
the blinking pattern of the A/T CHECK indicator or the malfunction indicator lamp (MIL). Refer to the table
on AT- 9 4 , "
SELF-DIAGNOSTIC RESULT MODE" for the indicator used to display each self-diagnostic
result.
The self-diagnostic results indicated by the MIL are automatically stored in both the ECM and TCM mem-
ories.
Always perform the procedure on AT- 3 9 , "
HOW TO ERASE DTC" to complete the repair and avoid
unnecessary blinking of the MIL.
For details of OBD-II, refer to EC-53, "
ON BOARD DIAGNOSTIC (OBD) SYSTEM" (for VQ35DE) or EC-703,
"ON BOARD DIAGNOSTIC (OBD) SYSTEM" (for VK45DE).
Certain systems and components, especially those related to OBD, may use the new style slide-
locking type harness connector. For description and how to disconnect, refer to PG-74, "
HAR-
NESS CONNECTOR" .
Wiring Diagrams and Trouble DiagnosisACS002L8
When you read wiring diagrams, refer to the following:
GI-15, "How to Read Wiring Diagrams".
PG-3, "POWER SUPPLY ROUTING CIRCUIT" for power distribution circuit.
When you perform trouble diagnosis, refer to the following:
GI-11, "How to Follow Trouble Diagnoses".
GI-27, "How to Perform Efficient Diagnosis for an Electrical Incident".
AT-30
A/T CONTROL SYSTEM
Revision: 2004 November 2004 FX35/FX45
TCM FunctionACS002LF
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 sensor
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 switchShift 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 systemInput 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: 2004 November 2004 FX35/FX45
During Shift Change
The necessary and adequate line pressure for shift change is set.
For this reason, line pressure pattern setting corresponds to input
torque and gearshift selection. Also, line pressure characteristic is
set according to engine speed, during engine brake operation.
At Low Fluid Temperature
When the A/T fluid temperature drops below the prescribed tempera-
ture, in order to speed up the action of each friction element, the line
pressure is set higher than the normal line pressure characteristic.
Shift ControlACS002LJ
The clutch pressure control solenoid is controlled by the signals from the switches and sensors. Thus, the
clutch pressure is adjusted to be appropriate to the engine load state and vehicle driving state. It becomes
possible to finely control the clutch hydraulic pressure with high precision and a smoother shift change charac-
teristic is attained.
SHIFT CHANGE
The clutch is controlled with the optimum timing and oil pressure by the engine speed, engine torque informa-
tion, etc.
PCIA0010E
PCIA0011E
PCIA0012E
AT-38
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Revision: 2004 November 2004 FX35/FX45
ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
IntroductionACS002LN
The A/T system has two self-diagnostic systems.
The first is the emission-related on board diagnostic system (OBD-II) performed by the TCM in combination
with the ECM. The malfunction is indicated by the MIL (malfunction indicator lamp) and is stored as a DTC in
the ECM memory but not the TCM memory.
The second is the TCM original self-diagnosis indicated by the A/T CHECK indicator lamp. The malfunction is
stored in the TCM memory. The detected items are overlapped with OBD-II self-diagnostic items. For detail,
refer to AT- 9 4 , "
Display Items List" .
OBD-II Function for A/T SystemACS002LO
The ECM provides emission-related on board diagnostic (OBD-II) functions for the A/T system. One function
is to receive a signal from the TCM used with OBD-related parts of the A/T system. The signal is sent to the
ECM when a malfunction occurs in the corresponding OBD-related part. The other function is to indicate a
diagnostic result by means of the MIL (malfunction indicator lamp) on the instrument panel. Sensors, switches
and solenoid valves are used as sensing elements.
The MIL automatically illuminates in One or Two Trip Detection Logic when a malfunction is sensed in relation
to A/T system parts.
One or Two Trip Detection Logic of OBD-IIACS002LP
ONE TRIP DETECTION LOGIC
If a malfunction is sensed during the first test drive, the MIL will illuminate and the malfunction will be stored in
the ECM memory as a DTC. The TCM is not provided with such a memory function.
TWO TRIP DETECTION LOGIC
When a malfunction is sensed during the first test drive, it is stored in the ECM memory as a 1st trip DTC
(diagnostic trouble code) or 1st trip freeze frame data. At this point, the MIL will not illuminate. — First Trip
If the same malfunction as that experienced during the first test drive is sensed during the second test drive,
the MIL will illuminate. — Second Trip
The “Trip” in the “One or Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation.
OBD-II Diagnostic Trouble Code (DTC)ACS002LQ
HOW TO READ DTC AND 1ST TRIP DTC
DTC and 1st trip DTC can be read by the following methods.
( with CONSULT-II or GST) CONSULT-II or GST (Generic Scan Tool) Examples: P0705, P0720 etc.
These DTC are prescribed by SAE J2012.
(CONSULT-II also displays the malfunctioning component or system.)
1st trip DTC No. is the same as DTC No.
Output of the diagnostic trouble code indicates that the indicated circuit has a malfunction. How-
ever, in case of the Mode II and GST, they do not indicate whether the malfunction is still occurring
or occurred in the past and returned to normal.
CONSULT-II can identify them as shown below, therefore, CONSULT-II (if available) is recom-
mended.
A sample of CONSULT-II display for DTC and 1st trip DTC is shown
on the next page. DTC or 1st trip DTC of a malfunction is displayed
in SELF-DIAGNOSTIC RESULTS mode for “ENGINE” with CON-
SULT-II. Time data indicates how many times the vehicle was driven
after the last detection of a DTC.
SAT014K
TROUBLE DIAGNOSIS
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A/T Interlock
If there is an A/T interlock judgment malfunction, the transmission is fixed in 2nd gear to make driving pos-
sible.
NOTE:
When the vehicle is driven fixed in 2nd gear a turbine revolution sensor malfunction is displayed,
but this is not a turbine revolution sensor malfunction.
When the coupling pattern below is detected, the fail-safe action corresponding to the pattern is executed.
A/T INTERLOCK COUPLING PATTERN TABLE
: NG X: OK
A/T 1st Engine Braking
When there is an A/T first gear engine brake judgment malfunction, the low coast brake solenoid is
switched “OFF” to avoid the engine brake operation.
Line Pressure Solenoid
The solenoid is switched “OFF” and the line pressure is set to the maximum hydraulic pressure to make
driving possible.
Torque Converter Clutch Solenoid
The solenoid is switched “OFF” to release the lock-up.
Low Coast Brake Solenoid
When a malfunction (electrical or functional) occurs, in order to make driving possible, if the solenoid is
“ON”, the transmission is held in 2nd gear; if the solenoid is “OFF”, the transmission is held in 4th gear.
(engine brake is not applied in 1st and 2nd gear.)
Input Clutch Solenoid
If a malfunction (electrical or functional) occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4th gear to make driving possible.
Direct Clutch Solenoid
If a malfunction (electrical or functional) occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4th gear to make driving possible.
Front Brake Solenoid
If a malfunction (electrical or functional) occurs with the solenoid “ON”, in order to make driving possible,
the A/T is held in 5th gear; if the solenoid is OFF, 4th gear.
High and Low Reverse Clutch Solenoid
If a malfunction (electrical or functional) occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4th gear to make driving possible.
Turbine Revolution Sensor 1 or 2
The control is the same as if there were no turbine revolution sensors, 5th gear and manual mode are pro-
hibited.
Gear positionATF pressure switch output
Fail-safe
functionClutch pressure output pattern after fail-safe func-
tion
SW3
(I/C)SW6
(HLR/
C)SW5
(D/C)SW1
(FR/B)SW2
(LC/B)I/C HLR/C D/C FR/B LC/B L/U
A/T inter-
lock cou-
pling pattern3rd – X X –Held in
2nd gearOFF OFF ON OFF OFF OFF
4th – X X –Held in
2nd gearOFF OFF ON OFF OFF OFF
5th X X – XHeld in
2nd gearOFF OFF ON OFF OFF OFF
AT-44
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
How To Perform Trouble Diagnosis For Quick and Accurate RepairACS007A4
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 5 , "
WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a drive ability 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 6
) should be used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot drive ability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
SAT631IB
SAT632I
SEF234G
TROUBLE DIAGNOSIS
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Revision: 2004 November 2004 FX35/FX45
Cruise Test - Part 3ACS007AC
1. MANUAL MODE FUNCTION
Move to manual mode from D position.
Does it switch to manual mode?
YES >> GO TO 2.
NO >> Continue road test and add checkmark to “Cannot Be Changed To Manual Mode” on diagnostics
worksheet AT- 4 6
.
2. CHECK SHIFT DOWN
During manual mode driving, is downshift from M5 → M4 → M3 → M2 → M1 performed?
With CONSULT-II
Read the gear position. Refer to AT- 9 7 , "
DATA MONITOR MODE" .
Is downshifting correctly performed?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle Does Not Shift” at the corresponding position (5th → 4th, 4th →
3rd, 3rd → 2nd, 2nd → 1st) on the diagnostics worksheet AT- 4 6
, then continue the road test.
3. CHECK ENGINE BRAKE
Check engine brake.
Does engine braking effectively reduce speed in M1 position?
YES >> 1. Stop the vehicle.
2. Carry out the self-diagnostics. Refer to AT- 9 4 , "
SELF-DIAGNOSTIC RESULT MODE" , AT- 1 0 3 ,
"Diagnostic Procedure Without CONSULT-II" .
NO >> Enter a check mark at “Vehicle Does Not Decelerate By Engine Brake” on the diagnostics work-
sheet AT- 4 6
, then continue trouble diagnosis.