AT-38
A/T CONTROL SYSTEM
Revision: 2007 April2007 M35/M45
Engine Brake ControlNCS001JV
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 ValveNCS001JW
FUNCTION OF CONTROL VALVE
SCIA1520E
Name Function
Torque converter regulator valveIn 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 sleeveAdjusts the oil discharged from the oil pump to the optimum pressure (line pressure) for
the driving state.
Front brake control valveWhen 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 valveAdjusts 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 AAdjusts the line pressure and produces the constant pressure (pilot pressure) required
for line pressure control, shift change control, and lock-up control.
Pilot valve BAdjusts 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 valveWhen 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 valveWhen 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
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Revision: 2007 April2007 M35/M45
FUNCTION OF PRESSURE SWITCH
Input clutch control valveWhen 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 valveWhen 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 sleeveSwitches the lock-up to operating or released. Also, by performing the lock-up operation
transiently, lock-up smoothly.
Torque converter lubrication valveOperates 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 valveSends 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-44
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
TROUBLE DIAGNOSISPFP:00004
DTC Inspection Priority ChartNCS001K2
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 DTC, first perform the trouble diagnosis for “DTC U1000 CAN
COMMUNICATION LINE”. Refer to AT- 1 0 5
.
Fail-safeNCS001K3
The TCM has an electrical fail-safe mode. This mode makes it possible to operate even if there is 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 A/T is fixed in 2nd, 4th and 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 A/T 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 A/
T 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 accord-
ing 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 accord-
ing 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 indicating 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
TROUBLE DIAGNOSIS
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Revision: 2007 April2007 M35/M45
A/T Interlock
If there is an A/T interlock judgment malfunction, the A/T is fixed in 2nd gear to make driving possible.
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 per-
formed.
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 A/T is held in 2nd gear. If the solenoid is OFF, the A/T 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 A/T 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 A/T 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, the A/T is 4th gear.
High and Low Reverse Clutch Solenoid
If a (electrical or functional) malfunction occurs with the solenoid either ON or OFF, the A/T 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-48
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
DIAGNOSTIC WORKSHEET
Information from Customer
KEY POINTS
WHAT..... Vehicle and A/T model
WHEN..... Date, Frequencies
WHERE..... Road conditions
HOW..... Operating conditions, Symptoms
Diagnostic Worksheet Chart
Customer name MR/MS Model and Year VIN
Trans. Model Engine Mileage
Malfunction Date Manuf. Date In Service Date
Frequency❏ Continuous❏ Intermittent ( times a day)
Symptoms❏ Vehicle does not move. (❏ Any position❏ Particular position)
❏ No up-shift (❏ 1st → 2nd❏ 2nd → 3rd❏ 3rd → 4th ❏ 4th → 5th)
❏ No down-shift (❏ 5th → 4th ❏ 4th → 3rd❏ 3rd → 2nd❏ 2nd → 1st)
❏ Lock-up malfunction
❏ Shift point too high or too low.
❏ Shift shock or slip (❏ N → D❏ N → R❏ Lock-up❏ Any drive position)
❏ Noise or vibration
❏ No kick down
❏ No pattern select
❏ Others
()
A/T CHECK indicator lamp❏ Continuously lit❏ Not lit
Malfunction indicator lamp (MIL)❏ Continuously lit❏ Not lit
1❏ Read the item on cautions concerning fail-safe and understand the customer's complaint.AT- 4 4
2❏ A/T fluid inspectionAT- 5 3❏ Leak (Repair leak location.)
❏ State
❏ Amount
3❏ Stall test and line pressure testAT- 5 3
, AT-
55❏ Stall test
❏ Torque converter one-way clutch
❏ Front brake
❏ High and low reverse clutch
❏ Low coast brake
❏ Forward brake
❏ Reverse brake
❏ Forward one-way clutch❏ 1st one-way clutch
❏ 3rd one-way clutch
❏ Engine
❏ Line pressure low
❏ Except for input clutch and direct
clutch, clutches and brakes OK
❏ Line pressure inspection - Suspected part:
TROUBLE DIAGNOSIS
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4❏ Perform all road tests and enter checks in required inspection items.AT- 5 7
4-1.Check before engine is started AT- 5 7
❏ AT- 1 9 0 , "A/T CHECK Indicator Lamp Does Not Come On"
❏ Perform self-diagnostics. Enter checks for detected items. AT- 9 2 ,AT-103
❏ AT-105, "DTC U1000 CAN COMMUNICATION LINE"
❏ AT-108, "DTC P0615 START SIGNAL CIRCUIT"
❏ AT-112, "DTC P0700 TCM"
❏ AT-113, "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT-117, "DTC P0717 TURBINE REVOLUTION SENSOR"
❏ AT-119, "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT-124, "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT-126, "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT-128, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT-130, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT-132, "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT-135, "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT-140, "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT-142, "DTC P1730 A/T INTERLOCK"
❏ AT-145, "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT-147, "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT-149, "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-151, "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT-153, "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT-155, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT-157, "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-159, "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT-161, "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT-163, "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT-165, "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT-167, "DTC P1815 MANUAL MODE SWITCH"
❏ AT-172, "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT-174, "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT-176, "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT-178, "DTC P1846 ATF PRESSURE SWITCH 6"
4-2.Check at IdleAT- 5 7
❏ AT- 1 9 0 , "Engine Cannot Be Started in “P” or “N” Position"
❏ AT- 1 9 1 , "In “P” Position, Vehicle Moves When Pushed"
❏ AT- 1 9 2 , "In “N” Position, Vehicle Moves"
❏ AT- 1 9 3 , "Large Shock (“N” to “D” Position)"
❏ AT- 1 9 5 , "Vehicle Does Not Creep Backward in “R” Position"
❏ AT- 1 9 7 , "Vehicle Does Not Creep Forward in “D” Position"
4-3.Cruise TestAT- 5 9
Part 1
❏ AT- 1 9 9 , "
Vehicle Cannot Be Started from D1"
❏ AT- 2 0 1 , "A/T Does Not Shift: D1 → D2"
❏ AT- 2 0 3 , "A/T Does Not Shift: D2 → D3"
❏ AT- 2 0 5 , "A/T Does Not Shift: D3 → D4"
❏ AT- 2 0 7 , "A/T Does Not Shift: D4 → D5"
❏ AT- 2 0 9 , "A/T Does Not Lock-up"
❏ AT- 2 1 0 , "A/T Does Not Hold Lock-up Condition"
❏ AT- 2 1 2 , "Lock-up Is Not Released"
❏ AT- 2 1 2 , "Engine Speed Does Not Return to Idle"
AT-50
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
44-3Part 2AT- 6 1
❏ AT-199, "Vehicle Cannot Be Started from D1"
❏ AT-201, "A/T Does Not Shift: D1 → D2"
❏ AT-203, "A/T Does Not Shift: D2 → D3"
❏ AT-205, "A/T Does Not Shift: D3 → D4"
Part 3AT- 6 1
❏ AT-213, "Cannot Be Changed to Manual Mode"
❏ AT-214, "A/T Does Not Shift: 5th Gear → 4th Gear"
❏ AT-215, "A/T Does Not Shift: 4th Gear → 3rd Gear"
❏ AT-217, "A/T Does Not Shift: 3rd Gear → 2nd Gear"
❏ AT-218, "A/T Does Not Shift: 2nd Gear → 1st Gear"
❏ AT-220, "Vehicle Does Not Decelerate by Engine Brake"
❏ Perform self-diagnostics. Enter checks for detected items. AT- 9 2 , AT-103
❏ AT-105, "DTC U1000 CAN COMMUNICATION LINE"
❏ AT-108, "DTC P0615 START SIGNAL CIRCUIT"
❏ AT- 11 2 , "DTC P0700 TCM"
❏ AT- 11 3 , "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT- 11 7 , "DTC P0717 TURBINE REVOLUTION SENSOR"
❏ AT- 11 9 , "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT-124, "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT-126, "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT-128, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT-130, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT-132, "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT-135, "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT-140, "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT-142, "DTC P1730 A/T INTERLOCK"
❏ AT-145, "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT-147, "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT-149, "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-151, "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT-153, "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT-155, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT-157, "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-159, "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT-161, "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT-163, "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT-165, "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT-167, "DTC P1815 MANUAL MODE SWITCH"
❏ AT-172, "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT-174, "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT-176, "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT-178, "DTC P1846 ATF PRESSURE SWITCH 6"
5❏ Inspect each system for items found to be NG in the self-diagnostics and repair or replace the malfunctioning parts.
6❏ Perform all road tests and enter the checks again for the required items.AT- 5 7
7❏ For any remaining NG items, perform the “Diagnostics Procedure” and repair or replace the malfunctioning
parts. See the chart for diagnostics by symptoms. (This chart also contains other symptoms and inspection pro-
cedures.)AT- 6 4
8❏ Erase the results of the self-diagnostics from the TCM.AT- 9 6, AT-
104
TROUBLE DIAGNOSIS
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Revision: 2007 April2007 M35/M45
Inspections before Trouble DiagnosisNCS001K7
A/T FLUID CHECK
A/T Fluid Leakage and A/T Fluid Level Check
Inspect for A/T fluid leakage and check the A/T fluid level. Refer to AT- 1 3 , "Checking A/T Fluid" .
A/T Fluid Condition Check
Inspect the A/T fluid condition.
STALL TEST
Stall Test Procedure
1. Inspect the amount of engine oil. Replenish the engine oil if necessary.
2. Drive for about 10 minutes to warm up the vehicle so that the A/
T fluid temperature is 50 to 80°C (122 to 176°F). Inspect the
amount of ATF. Replenish if necessary.
3. Securely engage the parking brake so that the tires do not turn.
4. Engine start, apply foot brake, and place selector lever in “D”
position.
Fluid condition Conceivable Cause Required Operation
Varnished (viscous
varnish state)Clutch, brake
scorchedReplace the ATF and check the A/T
main unit and the vehicle for mal-
functions (wire harnesses, cooler
pipes, etc.)
Milky white or cloudy Water in the fluidReplace the ATF and check for
places where water is getting in.
Large amount of metal
powder mixed inUnusual wear of
sliding parts within
A/TReplace the ATF and check for
improper operation of the A/T.
SAT638A
SAT647B
SCIA7463E
SCIA6787E