AT-32
A/T CONTROL SYSTEM
Revision: 2006 July 2007 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-35
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Revision: 2006 July 2007 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 ControlNCS001B3
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
A/T CONTROL SYSTEM
Revision: 2006 July 2007 FX35/FX45
Engine Brake ControlNCS001B5
The forward one-way clutch transmits the drive force from the engine to the rear wheels. But the reverse
drive from the rear wheels is not transmitted to the engine because the one-way clutch is idling.
Therefore, the low coast brake solenoid is operated to prevent the forward one-way clutch from idling and
the engine brake is operated in the same manner as conventionally.
The operation of the low coast brake solenoid switches the low coast brake switching valve and controls
the coupling and releasing of the low coast brake.
The low coast brake reducing valve controls the low coast brake coupling force.
Control ValveNCS001B6
FUNCTION OF CONTROL VALVE
SCIA1520E
Name Function
Torque converter regulator valve In order to prevent the pressure supplied to the torque converter from being excessive,
the line pressure is adjusted to the optimum pressure (torque converter operating pres-
sure).
Pressure regulator valve
Pressure regulator plug
Pressure regulator sleeve Adjusts the oil discharged from the oil pump to the optimum pressure (line pressure) for
the driving state.
Front brake control valve When the front brake is coupled, adjusts the line pressure to the optimum pressure
(front brake pressure) and supplies it to the front brake. (In 1st, 2nd, 3rd, and 5th gears,
adjusts the clutch pressure.)
Accumulator control valve Adjusts the pressure (accumulator control pressure) acting on the accumulator piston
and low coast reducing valve to the pressure appropriate to the driving state.
Pilot valve A Adjusts the line pressure and produces the constant pressure (pilot pressure) required
for line pressure control, shift change control, and lock-up control.
Pilot valve B Adjusts the line pressure and produces the constant pressure (pilot pressure) required
for shift change control.
Low coast brake switching valve During engine braking, supplies the line pressure to the low coast brake reducing valve.
Low coast brake reducing valve When the low coast brake is coupled, adjusts the line pressure to the optimum pressure
(low coast brake pressure) and supplies it to the low coast brake.
N-R accumulator Produces the stabilizing pressure for when N-R is selected.
Direct clutch piston switching valve Operates in 4th gear and switches the direct clutch coupling capacity.
High and low reverse clutch control valve When the high and low reverse clutch is coupled, adjusts the line pressure to the opti-
mum pressure (high and low reverse clutch pressure) and supplies it to the high and low
reverse clutch. (In 1st, 3rd, 4th and 5th gears, adjusts the clutch pressure.)
A/T CONTROL SYSTEM AT-39
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Revision: 2006 July 2007 FX35/FX45
FUNCTION OF ATF PRESSURE SWITCH
Input clutch control valve When the input clutch is coupled, adjusts the line pressure to the optimum pressure
(input clutch pressure) and supplies it to the input clutch. (In 4th and 5th gears, adjusts
the clutch pressure.)
Direct clutch control valve When the direct clutch is coupled, adjusts the line pressure to the optimum pressure
(direct clutch pressure) and supplies it to the direct clutch. (In 2nd, 3rd, and 4th gears,
adjusts the clutch pressure.)
TCC control valve
TCC control plug
TCC control sleeve Switches the lock-up to operating or released. Also, by performing the lock-up operation
transiently, lock-up smoothly.
Torque converter lubrication valve Operates during lock-up to switch the torque converter, cooling, and lubrication system
oil passage.
Cool bypass valve Allows excess oil to bypass cooler circuit without being fed into it.
Line pressure relief valve Discharges excess oil from line pressure circuit.
N-D accumulator Produces the stabilizing pressure for when N-D is selected.
Manual valve Sends line pressure to each circuit according to the select position. The circuits to which
the line pressure is not sent drain.
Name Function
Name Function
ATF pressure switch 1 (FR/B) Detects any malfunction in the front brake hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
ATF pressure switch 2 (LC/B) Detects any malfunction in the low coast brake hydraulic pressure. When it detects any
malfunction, it puts the system into fail-safe mode.
ATF pressure switch 3 (I/C) Detects any malfunction in the input clutch hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
ATF pressure switch 5 (D/C) Detects any malfunction in the direct clutch hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
ATF pressure switch 6 (HLR/C) Detects any malfunction in the high and low reverse clutch hydraulic pressure. When it
detects any malfunction, it puts the system into fail-safe mode.
AT-40
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Revision: 2006 July 2007 FX35/FX45
ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
IntroductionNCS001B7
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 2 , "
Display Items List" .
OBD-II Function for A/T SystemNCS001B8
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 rela-
tion to A/T system parts.
One or Two Trip Detection Logic of OBD-IINCS001B9
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. — 1st trip
If the same malfunction as that experienced during the first test drive is sensed during the second test drive,
the MIL will illuminate. — 2nd 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)NCS001BA
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.
BCIA0030E
AT-112
DTC P0705 PARK/NEUTRAL POSITION SWITCH
Revision: 2006 July 2007 FX35/FX45
DTC P0705 PARK/NEUTRAL POSITION SWITCHPFP:32006
DescriptionNCS001CB
The PNP switch includes a transmission range switch.
The transmission range switch detects the selector lever position and sends a signal to the TCM.
CONSULT-II Reference ValueNCS001CC
On Board Diagnosis LogicNCS001CD
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “P0705 PNP SW/CIRC” with CONSULT-II or 9th judgement flicker without CON-
SULT-II is detected under the following conditions.
–When TCM does not receive the correct voltage signal from the PNP switches 1, 2, 3 and 4 based on the
gear position.
–When no other position but “P” position is detected from “N” position.
Possible CauseNCS001CE
Harness or connectors
(PNP switches 1, 2, 3 and 4 and TCM circuit is open or shorted.)
PNP switches 1, 2, 3 and 4
DTC Confirmation ProcedureNCS001CF
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “ECU INPUT SIGNALS” or “MAIN SIGNALS” in “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Touch “START”.
4. Start engine.
5. Drive vehicle and maintain the following conditions for at least 2 consecutive seconds.
ACCELE POSI: More than 1.0/8
6. If DTC is detected, go to AT- 11 4 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II”.
Item name Condition Display value
SLCT LVR POSI Selector lever in “N” and “P” positions. N/P
Selector lever in “R” position. R
Selector lever in “D” position. D
BCIA0031E
AT-166
DTC P1815 MANUAL MODE SWITCH
Revision: 2006 July 2007 FX35/FX45
DTC P1815 MANUAL MODE SWITCHPFP:34901
DescriptionNCS001GD
Manual mode switch is installed in A/T device. It sends manual mode switch, shift up and shift down switch
signals to TCM.
TCM sends the switch signals to unified meter and A/C amp. By CAN communication line. Then manual mode
switch position is indicated on the A/T indicator. For inspection, refer to AT- 1 8 5 , "
A/T INDICATOR CIRCUIT" .
CONSULT-II Reference Value in Data Monitor ModeNCS001GE
On Board Diagnosis LogicNCS001GF
This is not an OBD-II self-diagnostic item.
Diagnostic trouble code “P1815 MANU MODE SW/CIR” with CONSULT-II is detected when TCM moni-
tors Manual mode, Non manual mode, Up or Down switch signal, and detects as irregular when impossi-
ble input pattern occurs 1 second or more.
Possible CauseNCS001GG
Harness or connectors
(These switches circuit is open or shorted.)
Manual mode select switch (Into control device)
Manual mode position select switch (Into control device)
DTC Confirmation ProcedureNCS001GH
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 2 consecutive seconds.
MANU MODE SW: ON
5. If DTC is detected, go to AT- 1 6 9 , "
Diagnostic Procedure" .
Item name Condition Display Value
MANU MODE SW Manual shift gate position (neutral) ON
Other than the above OFF
NON M-MODE SW Manual shift gate position OFF
Other than the above ON
UP SW LEVER selector lever: + side ON
Other than the above OFF
DOWN SW LEVER selector lever: - side ON
Other than the above OFF
BCIA0031E
ATC-2Revision: 2006 July 2007 FX35/FX45
A/C SWITCH ....................................................
... 35
MODE SWITCH ................................................ ... 35
FAN SWITCH ................................................... ... 35
DUAL SWITCH ................................................. ... 35
Fail-safe Function ................................................ ... 36
Discharge Air Flow .............................................. ... 37
System Description .............................................. ... 38
SWITCHES AND THEIR CONTROL FUNCTION ... 38
CAN Communication System Description ........... ... 39
TROUBLE DIAGNOSIS ......................................... ... 40
CONSULT-II Function (BCM) ............................... ... 40
CONSULT-II BASIC OPERATION .................... ... 40
DATA MONITOR ............................................... ... 40
How to Perform Trouble Diagnosis for Quick and
Accurate Repair ................................................... ... 40
WORK FLOW ................................................... ... 40
SYMPTOM TABLE ........................................... ... 41
Component Parts and Harness Connector Location ... 42
ENGINE COMPARTMENT ............................... ... 42
PASSENGER COMPARTMENT ....................... ... 43
Schematic ............................................................ ... 44
Wiring Diagram — A/C — .................................... ... 45
Auto Amp. Terminals and Reference Value ......... ... 50
PIN CONNECTOR TERMINAL LAYOUT ......... ... 50
TERMINALS AND REFERENCE VALUE FOR
UNIFIED METER AND A/C AMP. ..................... ... 50
Self-diagnosis Function ....................................... ... 52
DESCRIPTION ................................................. ... 52
FUNCTION CONFIRMATION PROCEDURE ... ... 53
AUXILIARY MECHANISM: TEMPERATURE
SETTING TRIMMER ........................................ ... 58
AUXILIARY MECHANISM: FOOT POSITION
SETTING TRIMMER ........................................ ... 59
AUXILIARY MECHANISM: INLET PORT MEM-
ORY FUNCTION .............................................. ... 59
Operational Check ............................................... ... 60
CHECKING MEMORY FUNCTION .................. ... 60
CHECKING BLOWER ...................................... ... 60
CHECKING DISCHARGE AIR ......................... ... 60
CHECKING INTAKE AIR .................................. ... 60
CHECKING TEMPERATURE DECREASE ...... ... 60
CHECKING TEMPERATURE INCREASE ....... ... 60
CHECKING A/C SWITCH ................................ ... 61
CHECKING AUTO MODE ................................ ... 61
Power Supply and Ground Circuit for Auto Amp. ... 62 INSPECTION FLOW ........................................ ... 62
COMPONENT DESCRIPTION ......................... ... 62
DIAGNOSIS PROCEDURE FOR A/C SYSTEM ... 63
LAN System Circuit ............................................. ... 64
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT ... 64
Mode Door Motor Circuit ..................................... ... 68
INSPECTION FLOW ........................................ ... 68
SYSTEM DESCRIPTION ................................. ... 69
COMPONENT DESCRIPTION ......................... ... 70
DIAGNOSIS PROCEDURE FOR MODE DOOR
MOTOR ............................................................ ... 70
Air Mix Door Motor Circuit ................................... ... 71
INSPECTION FLOW ........................................ ... 71 SYSTEM DESCRIPTION ..................................
... 72
COMPONENT DESCRIPTION ......................... ... 73
DIAGNOSIS PROCEDURE FOR AIR MIX DOOR
MOTOR ............................................................. ... 73
Air Mix Door Motor PBR Circuit ........................... ... 73
DIAGNOSIS PROCEDURE FOR AIR MIX DOOR
MOTOR PBR .................................................... ... 73
Intake Door Motor Circuit ..................................... ... 74
INSPECTION FLOW ......................................... ... 74
SYSTEM DESCRIPTION .................................. ... 75
COMPONENT DESCRIPTION ......................... ... 76
DIAGNOSIS PROCEDURE FOR INTAKE DOOR
MOTOR ............................................................. ... 76
Blower Motor Circuit ............................................. ... 77
INSPECTION FLOW ......................................... ... 77
SYSTEM DESCRIPTION .................................. ... 78
COMPONENT DESCRIPTION ......................... ... 79
DIAGNOSIS PROCEDURE FOR BLOWER
MOTOR ............................................................. ... 79
COMPONENT INSPECTION ............................ ... 81
Magnet Clutch Circuit ........................................... ... 82
INSPECTION FLOW ......................................... ... 82
SYSTEM DESCRIPTION .................................. ... 83
DIAGNOSIS PROCEDURE FOR MAGNET
CLUTCH ........................................................... ... 83
COMPONENT INSPECTION ............................ ... 89
Insufficient Cooling ............................................... ... 90
INSPECTION FLOW ......................................... ... 90
PERFORMANCE TEST DIAGNOSIS ............... ... 92
PERFORMANCE CHART ................................. ... 94
TROUBLE DIAGNOSIS FOR UNUSUAL PRES-
SURE ................................................................ ... 95
DIAGNOSIS PROCEDURE FOR INSUFFI-
CIENT COOLING .............................................. ... 97
Insufficient Heating .............................................. ... 99
INSPECTION FLOW ......................................... ... 99
Noise .................................................................... .100
INSPECTION FLOW ......................................... .100
Self-diagnosis ...................................................... .101
INSPECTION FLOW ......................................... .101
Memory Function ................................................. .102
INSPECTION FLOW ......................................... .102
Ambient Sensor Circuit ........................................ .103
COMPONENT DESCRIPTION ......................... .103
AMBIENT TEMPERATURE INPUT PROCESS .103
DIAGNOSIS PROCEDURE FOR AMBIENT
SENSOR ........................................................... .103
COMPONENT INSPECTION ............................ .105
In-vehicle Sensor Circuit ...................................... .106
COMPONENT DESCRIPTION ......................... .106
DIAGNOSIS PROCEDURE FOR IN-VEHICLE
SENSOR ........................................................... .107
COMPONENT INSPECTION ............................ .108
Sunload Sensor Circuit ........................................ .109
COMPONENT DESCRIPTION ......................... .109
SUNLOAD INPUT PROCESS .......................... .109
DIAGNOSIS PROCEDURE FOR SUNLOAD
SENSOR ........................................................... .109