Automatic Transaxle
1.
Introduction
2.
A5SR2
3.
Overhaul
Copyright by Hyundai Motor Company.
All rights reserved.
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To know the automatic transaxle systems of TQ
Objective
Understand the function of A5SR2.
To be able to do a proper maintenance on this system
.
The automatic transaxle for TQ car is a newly developed 5-speed FR automatic
transmission which is applied in Hyundai for the first time. It will be equipped in A-2.5
VGT engine only for General area. In this training manual, the overall system features,
electronic control system and diagnosis will be handled.
For more detail information or
specifications, please refer to the relevant workshop manual and electrical
troubleshooting manual.
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1. Introduction
1.1 T/M Variation
TQ has newly developed FR (front engine rear driving) automatic transmission but it is applied only
for general market.
Only three countries Australia (right hand drive, RHD), Taiwan (LHD) and
Philippine (LHD) will have this new A/T. Originally this model is being applied in KIA SORENTO
from 2004MY and it was imported from JATCO and highly focused because it was the first launch of
5-speed rear driving A/T in Hyundai-Kia Automotive group. Hyundai Powertec is producing the
transmission for TQ and KIA SORENTO.
‘RXC’ is an another name of this model used in
JATCO (it can be found in some other document) and is being applied in Nissan Infinity.
But be
sure that it’s official model name is ‘A5SR2’.
‘A’: it means automatic transmission
‘5’: 5 speed
‘S’: it means the torque transmitting capacity. The maximum torque for this model is 45kgfm.
‘G’ and ‘H’ for A5GF1 or A5HF1 for TG or CM has lower torque capacity because it’s alphabet
position is earlier than ‘S’. S’ will stand for the maximum torque among all A/T model in
Hyundai at this moment.
‘2’: it means the 2nd variation in the same transmission model, surely we have ‘A5SR1’
applied with theta2.0 for BK. (Next model of GK)
The main reason to develop new A/T is to cope with high torque in A-2.5 engine. The existing
AISIN FR A/T (4-speed) has only 35kgfm of maximum torque. On the other hand, EU will have only
manual transmission. When starts TQ project, there was A/T option with A-2.5 for EU, but it was
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cancelled to develop to reduce the cost and launching time. For M5SR1 for A-2.5 is basically same
model applied in HP.
Dual mass flywheel and Self adjusting clutch will be applied for enhancing
driving performance and quality.
1.2 Manual Transmission
M5TR1-1:
The overall weight has been reduced and the gear ratio was modified to improve the climbing ability
comparing with the previous M5TR1.
From double brass mechanism, the single synchronizer cone
has been applied in 3rd-Rerverse gear for better shift feeling and durability.
M5TR1 profile
M5TR1-1
profile
Decreased weight due to the reduced volume : 47.9  44.5kg
Reduced oil quantity : 2.2  1.95ℓ
Advanced M5SR1:
The gear ratio was optimized for better fuel
consumption.
Dual mass flywheel applied for
lower noise in driving train and rattle noise.
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The triple synchronizer was applied in 1st –
2nd gear as shown in following picture.
1.3 AW30-40/43
Basically this model already applied in HP and old H-1. Just some shit lever and bracket has been
changed and the TCM has been recalibrated for corresponding to the different engine specification.
Refer to the followings for the warning lamp variations.
NO.
Warning lamps
Specification
TQ A5SR2
TQ AW30-40/43
A2.5 VGT
D4BH TCI
Θ-2.4
1
A/T TEMP
X
X
X
2
POWER
X
X
X
3
HOLD (SNOW)
X
X
X
4
O/D OFF
X
O
O
5
Lever type
Sports mode
7
6-positions (PRND2L)
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2. A5SR2
2.1 Main Features
Clutch to clutch control:
Every clutch and brake is controlled independently by electronic controlled solenoid valve like HIVEC
A/T.
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Sports mode:
H-MATIC lever was added for manually powerful driving which has been adopted in HIVEC A/T.
As soon as the sports mode is selected (even the ‘-‘ was not selected) from ‘D’range while driving
with 5th gear, the gear will be downshifted into 4th gear in order to adopt the driver’s intention
previously.
(Be sure that this is not a fault but a normal driving control)
The current gear position displays in sports mode only and the vehicle can start with 2nd gear at
sports mode. Also there is a DTC for Sports mode switch.
Two turbine speed sensor:
To detect the input turbine speed depending on the gear position, one more input/turbine speed sensor
was added.
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A/T Sub ROM unit:
The P-I value (P: Pressure, I: Current consumption) for each valve body will be recorded on the A/T
sub ROM unit on the valve body.
This information will be sent to main TCM to compensate the
hydraulic characteristics of each valve body while shift control.
Two ATF temperature sensors:
For the accurate control, totally two ATF sensors are installed in the oil pan and the outlet port of the
torque converter.
Multiple disc type lock-up clutch:
Type: 3Elements, 2Phases, 1stage
The multiple disc type lock-up clutch (damper clutch, torque converter clutch) is applied to improve the
durability and the responding time. It enables the overall operating area of lock-up to be enlarged.
The multiple disc type lock-up clutch has a merit that it can be applied the smaller lock-up clutch
diameter comparing with the conventional radial single plate type.
This enables the dynamic
resistance to be decreased and the overall efficiency of torque converter to be enhanced.
Also it
allows the more wide operating range of lock-up clutch.
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However, the multiple disc type lock-up clutch increases the overall height of torque converter so that
generally it is not applied in FF type A/T because it is very sensitive and important to reduce the overall
transaxle length in case of FF type.
Inhibitor switch:
The current range will be informed to TCM from the linear type inhibitor switch. The range signal is a
digital code so the start relay is directly controlled by TCM.
inhibitor switch but TCM through the reverse lamp relay.
The reverse lamp is controlled by not
It is not necessary to adjust the shift cable
clearance for the N range of rotary type inhibitor switch
Oil pressure switch:
Five oil pressure switches are installed on the valve body for the interlock prevention and fail safe
function. It will be handled in detail in the section of ‘Oil pressure switch’.
TCM:
KEFICO TCM is applied for TQ. It’s location is nearby ‘A’ pillar of driver side.
It has two
terminal connectors but only one side is used for TCM only because it is not a ‘PCM’.
And the
independent ‘K-line’ is applied for the communication with the scan tool.
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2.2 Comparison
Items
AISIN
Hyundai Powertec
AW30-40LEi
A5SR2
Applied vehicle
H-1, HP
TQ A-2.5VGT
Max. Gear
4th Gear
5th Gear
Max. Torque (kgfm)
35
45
Number of OWC
3
3
Stall speed (rpm)
2,420(DSL)
2,585
254
250
Model
T/Converter DIA. (mm)
Planetary gear
3 Simple (Number of pinion)
3 Simple (Number of pinion)
- O/D (4), Front (4), Rear (4)
- Front (5), Middle (5), Rear (5)
Friction element
3C4B3F
3C4B3F
Gear
1st
2.804
3.730
ratio
2nd
1.531
2.308
3rd
1.000
1.159
4th
0.705
1.000
5th
-
0.840
R
2.393
2.740
Items
AISIN
Hyundai Powertec
AW30-40LEi
A5SR2
VFS: 1EA, ON/OFF: 3EA
VFS: 6EA, ON/OFF: 1EA
Model
Solenoid valve
Line pressure control
Fully variable line pressure control
Clutch to Clutch control
Number of TCM
Number of Sensor
5 sensors
No
Yes
1 (Main)
2 (1-Main+1-Sub ROM)
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- Input speed sensor
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12 sensors
- Input (Turbine) speed Sensor X 2
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2.3 Operating element
This transmission consists of
3 Clutches: Input clutch, High & Low reverse clutch, Direct clutch
4 Brakes: Front brake, Reverse brake, Forward brake, Low coasting brake
3 OWC: 1st OWC, Forward OWC, 3rd OWC
Operates and affects power transmission.
H: Hydraulic pressure is supplied but does not affect power transmission.
VS1: As soon as the wheel rotates, the pressure is released (D range only). The pressure is
restored in case of sports (manual) mode.
VS2: As soon as the wheel rotates, the pressure is applied. (Sports mode only)
M: Operates only when manual mode is selected.
A: Operates during accelerating.
C: Operates while vehicle is coasting.
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Three units of OWC are applied to restrict the rotating direction in the stage of shift and these clutches
restricts the sun gears as shown on the illustration.
The 3rd OWC located in the most front side restricts
the rotating direction of the front sun gear, 1st OWC located in the middle area restricts the rotating
direction of the rear sun gear and finally the forward OWC located in the back side restricts the rotating
direction of the middle sun gear.
Note:
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2.4 Inputs & Outputs
Solenoid valve (7EA)
System power
Starter relay
Inhibitor switch
Reverse lamp relay
Hydraulic pressure switch (5EA)
Shift lamp
Sub ROM unit
ATF temperature sensor 1,2
K-line
TCM
CAN line
Turbine speed sensor 1,2
TPS
Output speed sensor
Vehicle speed
Engine speed
Brake lamp switch
Engine torque, load
Sports mode switch
Note:
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2.5 Inhibitor switch
The linear stroke type inhibitor switch is applied and it sends the digital combined on, off code to TCM.
The starter motor cannot be operated through the inhibitor switch as in the case of conventional rotary
type switch. Independent starter relay controlled by TCM is added. The high capacity of wiring and
terminals were removed in the inhibitor switch for starter motor circuit. This enables the inhibitor switch to
get higher durability and lower trouble such as the ‘impossible to start the engine problem’ due to
the poor contact or wrong adjustment of the rotary type inhibitor switch.
It consists of the fixed terminal block and the moving block. The fixed terminal block is a heatproof
material and is designed to resist against the ATF oil. There are 10 terminals in the connector for each
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code switches, ground line, ATF temperature sensor and output speed sensor wiring. The ground line is
connected to the A/T case through the valve body assembly for the remedy of emergency such as
opened or shorted ground condition.
The material of moving block is same one for fixed terminal block and it has an electrical pole, what is
called ‘slider’. A driving pin built in the moving block is equipped. The slider is normally contacted on
the grounding line and it moves to the particular position by the operating of manual lever. It generates
the ON or OFF signal depends on the location from S1 to S4. That is, the ON/OFF switching happens
when the slider’s contact point of the moving block climbs on the fixed terminal block.
5 units of slider are installed that has a curled shape as shown on the picture
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The combination table for inhibitor switch codes
● : Each switch becomes ON (Ground level)
- TCM will recognize as a failed circuit if the ‘other signals’ not included the above table is detected.
☞ : “Other signals”: Because of opened circuit or shorted circuit (including of multiple signals), another
signals that is not shown on the above table may be sent to TCM and then TCM will detect the fault,
displays the DTC of P0705. (OBD regulation: P0705  The DTC of Transaxle range switch including of
opened or shorted circuit both)
Since the conventional rotary type switch was not applied in this automatic transmission, it is not
available to make a direct circuit for the starter motor operating at P or N range.
As the TCM receives
the code combination from the inhibitor switch, and then the TCM will make ground the starter motor
relay control line to operate the starter motor at P or N range. Be sure that it is impossible to start the
engine at P or N range if the DTC of inhibitor switch is detected by TCM.
On the other hand, the reverse lamp circuit also is not connected directly through the inhibitor switch.
As the TCM receives the code combination from the inhibitor switch, and then the TCM will make ground
the reverse lamp relay control line to operate the reverse lamp at R range. The current range lamp on
the cluster also is controlled by TCM.
It is also not directly connected from the inhibitor switch so the
TCM will control the lamp on or off on the cluster.
Be sure that the current range lamp on the cluster
may be turned off in case of some situation to inform the particular procedure or malfunction. That is,
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Every current range lamp (P, R, N, D) will be turned off if the DTC of the inhibitor switch is detected by
TCM.
R range lamp will be turned off when the erasing data in Sub ROM is completed.
- INH3 monitoring line
*ON: Less than 1.3V
*OFF: More than 4.0V
*INH3 MON:
Monitoring terminal to detect the open circuit of INH3 (S3) terminal
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As shown on the above table for the ON/OFF schedule depending on the position of inhibitor switch, two
terminals such as ‘INH3’ and ‘INH3 (MON)’ are sent to TCM through the Sub ROM unit.
If we erase
the old hydraulic pressure data of each valve body in Sub ROM whenever install the used TCM on the
other vehicle or, replace the A/T assembly, the valve body assembly with new one, the reverse range
must be selected for erasing that by Hi-scan, so the Sub ROM also should know the current range to
ready the communication with TCM.
The service data shows the situation when INH1 terminal is shorted to ground.
Even if the shift lever is
positioned at R range, it is controlled by D range so that the forward driving is available but the reverse
driving is not available. (However, the hesitation will occur in forwarding driving)
If the inhibitor switch is failed, the DTC of P0705 is detected and then the range will be fixed by “D”
range.
At the same time, the current range lamp on the cluster will be turned off, the starter relay turned
off (That is, impossible to start engine) and the reverse lamp relay will not be energized.
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2.6 Oil pressure switch
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In the case of the conventional
automatic
transmission,
the
TCM
monitors the open or shorted circuit of
solenoid
valve
by
controlling
solenoid
valve
current
and
the
some
mechanical hydraulic spool valve stuck
(especially for the regulator valve or
Items
Detected by
hydraulic pressure
switch
Reducing valve stuck
(clutch outlet port)
★
Solenoid valve stuck
(clutch outlet port)
★
Detected by
solenoid valve
current
★
Harness open, short
damper clutch control valve) can be
detected by indirect calculation logic in TCM.
But it was very difficult and inaccurate to detect or
monitor the stuck of solenoid valve or valve body spool valve.
For this reason, totally 5 units of
hydraulic pressure switch are applied on the valve body in this automatic transmission. TCM can
know the engaging or disengaging of each clutch or brake directly through the pressure switch so the
interlock can be prohibited by starting the fail safe mode for the system safety.
Be sure that this is not
a sensor but a switch. This means it is not used as a line pressure control factor for smooth shift
feeling. That is, TCM just can detect the time of engaging or disengaging and then decide to control
with normal shift pattern or fail safe mode.
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Note:
The schedule table for the hydraulic pressure switch signal (normal operating condition)
Shift
I/C
H&LR/C
D/C
Frt/B
positions
P, N
ON
R
ON
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ON
ON
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VS: Becomes “ON” in appropriate vehicle speed range.
M: Becomes “ON” only when manual (sports) mode is selected.
ON: It is grounded to zero voltage
The slide shows the signal change of oil pressure switch depending on the gear shifting.
Refer to
above table to check the signal output corresponding to the each gear position.
Be sure that there is no DTC only for the oil pressure switch itself. That is, if the oil pressure switch
circuit is failed, it may be detected as a particular solenoid valve failure.
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2.7 A/T Sub ROM
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The control valve body assembly and the A/T UNIT (Sub ROM) were unified with one unit and built in
transmission.
TCM communicates with this sub ROM to compensate the specific hydraulic
characteristics value for more accurate shift control and enhanced A/T durability.
That is, each produced valve body and automatic transmission has a different dimension, hydraulic
pressure response under the actual operating condition on the vehicle.
When the valve body is assembled with the transmission in the factory, the unique information is written
into the sub ROM.
As the automatic transmission assembly is equipped on the particular vehicle, TCM
will automatically read the written data from the sub ROM.
The above-mentioned ‘hydraulic pressure mapping data’ is classified by several kinds (No.1∼No.38)
of specified mapping number that is designated by A/T maker.
Hydraulic pressure tester inspects the
pressure (kPa) and current (mA) response curve of each valve body unit and match the result with the
one what she has. The unique specific hydraulic pressure mapping number is decided by tester and
automatically written in the sub ROM.
Be sure that this process is done at the A/T maker factory.
On the other hand, this Sub ROM unit is used for intermediate wiring line of turbine speed sensor,
inhibitor switch, output speed sensor, ATF temperature sensor and so on. As shown in the below
diagram, the turbine speed sensor power is supplied from the Sub ROM unit and the sensor ground line
is ground to the valve body assembly.
This means faulty Sub ROM unit can affect the malfunction of
the turbine speed sensor.
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Sub ROM communication
* Data bit, SEL 1, 2, 3:
Communication line between Sub ROM unit and TCM
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Among seven operating elements, the hydraulic pressure switch is not applied in the forward brake
and reverse brake because it is possible to get a fail-safe mode by manual valve.
Referring the
operating elements table in each gear position, reverse brake is engaged only in reverse gear and the
forward brake is engaged in all forward driving gears.
Totally three wires are used as a communication line between TCM and sub ROM as follows.
Line SEL1: Check sum signal while communication (Low coast brake hydraulic pressure switch)
Line SEL2: System clock signal while communication (Direct clutch hydraulic pressure switch)
Line SEL3: Data input signal while communication (Input clutch hydraulic pressure switch)
1) When the TCM is replaced with new one:
Nothing to do! Just turn the ignition key ON position, and then TCM will read the data from the sub
ROM automatically.
At that moment, the shift range lamp on the cluster will be turned off for about 1sec.
(The shift range lamp should be turned on continuously under the ignition key ON depending on the shift
range what the driver selected while normal condition.) This is the only way to check the TCM status is
virgin or learnt. It means that A/S parts (TCM) have a virgin status.
Be sure that the shift range lamp
on the cluster is actuated by TCM (not by the direct wiring from the inhibitor switches)
2) When the A/T assembly is replaced with new one or used one:
The recorded data inside of sub ROM must be erased. (The shift quality will become harsh if you do
not perform this procedure because the TCM cannot compensate the hydraulic pressure of each valve
body)
Put the shift lever on the ‘R’ range
Press the accelerator pedal to keep about 50% of TPS ratio
Erase the recorded data inside of sub ROM under the ignition key ON position using Hi-scan Pro.
As the data is erased, the shift range lamp on the cluster will be turned off.
Ignition key off and on, and then the TCM will read the data from the replaced new valve body.
It is same as above when the valve body only is replaced with new one or used one.
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3) When the used TCM (vehicle “A”) is assembled on the vehicle “B”:
It is same as “2)” procedure.
You may have a question why it is available only in ‘R’ range when you erase the old sub ROM data
inside of TCM by Hi-scan. Generally the DTC can be erased in “P” or “N” range and it is required for
Hi-scan to identify the different mode. If the ‘R’ range is selected and the diagnostic communication is
started, then the Hi-scan will be ready to erase a sub ROM data inside of TCM; otherwise the other DTC
may be erased unintentionally.
The communication between TCM and sub ROM is done through three wires. These wires are for
hydraulic pressure switch.
Each wire has two functions.
When the ignition key is turned on for the
first time, this hydraulic pressure switch wire is used as a communication line between TCM and sub
ROM if the TCM status is a virgin. If the TCM status is not a virgin anymore, TCM will not send a
request signal to sub ROM and these wires will be functioned as a hydraulic pressure switch to detect
the gear interlock.
Regarding the function and purpose of hydraulic pressure switches, it will be
explained in other section of this manual.
2.8 TCM Learning
Whenever it is done to erase the recorded data in sub ROM by Hi-scan, it is requested to perform the
TCM learning by driving the vehicle.
As the data in sub ROM is erased, the learnt data of A/T operating
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element including of hydraulic pressure characteristics also may be erased together. Its procedure is as
below.
Keep the TPS ratio about 1/8
Shift the gear from 1st to 4th at D range
Repeat the above automatic shift more than 3times.
This TCM learning is called “Stand By Learning Control” for better shift feeling. TCM learns the
hydraulic pressure filling time in each operating elements by monitoring the change of turbine speed
whenever the gearshift is occurred. TCM refers this data to control the pressure while the next shifting.
2.9 ATF Temperature Sensor 1, 2
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One more ATF temperature sensor is added in this transmission for more accurate shift control. As
same as others, it is a NTC type temperature sensor.
- ATF temperature sensor 1:
It detects the ATF temperature inside of oil pan.
inhibitor switch as in the above picture.
It is soaked in ATF always and is built inside of
The purpose and function of this sensor is same as the
conventional thing that is adopted on the previous automatic transmission. That is for line pressure
control, shift pattern control and so on. If this sensor is failed, the DTC of P0712 is detected and then
the sports mode control and the 5th gear will not be available. Refer to the following specification for
the output voltage and the internal resistance depending on the temperature.
Temperature
Resistance (kΩ)
Output voltage (V)
0℃(32℉)
Approx. 15
3.3
20℃(32℉)
Approx. 6.5
2.7
80℃(32℉)
Approx. 0.9
0.9
- ATF temperature sensor 2:
It is installed on the valve body as shown on the above picture. It mainly detects the ATF temperature
that flows to torque converter. ATF temperature from the torque converter is most high because the
torque converter is the area that the highest friction is occurred at the automatic transmission. That is
for mainly the high ATF temperature shift pattern control.
This inhibition is restored if the normal temperature is sensed over 124counts. Refer to the following
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specification for the output voltage and the internal resistance depending on the temperature.
Temperature
Resistance (kΩ)
Output voltage (V)
0℃(32℉)
Approx. 10.5
3.3
20℃(32℉)
Approx. 4.3
2.5
80℃(32℉)
Approx. 0.5
0.7
Mostly the ATF sensor 2 has shows higher temperature because of the sensor location (torque
converter outlet port) as shown in the GDS data in the slide.
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The slide shows the service data and DTC when ATF sensor 1 is shorted to ground.
•
DTC : P0712,
80°C fixed, 5th speed inhibited (D & S, 1st speed ↔ 4th speed)
•
Sports mode inhibited
The slide shows the service data that the ATF sensor 2 is shorted to ground.
•
No DTC (Normal operation), ATF sensor 2 data is same as ATF sensor 1
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2.10 Turbine Speed Sensor 1, 2
This automatic transmission has two input/turbine speed sensors. This is one of the most noticeable
points in this system. Two speed sensors are Hall IC type with digital active signals that are being used
in other system and A/T models.
1) Turbine speed sensor 2: It detects the turbine speed at 1st, 2nd, 3rd, 5th gear
2) Turbine speed sensor 1: It detects the turbine speed at 4th gear only.
Two sensors are built in one unit like a picture of right side and it is installed on the transmission case
to detect each different positions. Why there are two units of speed sensor?
You should understand the
operating element chart in each gear to know the reason.
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It is required to understand the previous AISIN automatic transmission (AW30-40LE model) that was
adopted on HP or old H-1. The input shaft rotation is as below in AW30-40LE model:
-
From 1st gear to 3rd gear: A certain RPM depend on the engine speed. The tone wheel speed
(overdrive sun gear and overdrive clutch drum speed) is same as input (turbine) speed.
-
At 4th gear: It becomes zero RPM because overdrive brake is engaged and it results the holding
of tone wheel for turbine speed sensor.
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In AW30-40LE model, as soon as the turbine speed is lower than 600rpm, the TCM detects the starts
of 3rd to 4th gear up-shift and controls the hydraulic pressure for the smooth shift feeling. Oppositely, as
the turbine speed is higher than 600rpm while driving with 4th gear, TCM starts to control the downshift
(4th to 3rd) hydraulic pressure for lower shift shock. It means TCM does not need to know the current
turbine speed while driving with 4th gear. If we have 5th gear in AW30-40LE model, TCM must know the
current turbine speed at 4th gear, but the 4th gear is a final maximum gear in AW30-40LE model.
That is why it is possible to control the overall gear shifting even though the turbine speed sensor value
becomes zero at the 4th gear.
Turbine speed sensor 1: It detects the rotating speed of the front brake drum
Turbine speed sensor 2: It detects the rotating speed of the rear planetary annulus gear
On the other hand, TCM must know the current turbine speed while driving with the 4th gear in this 5speed A5SR2 automatic transmission.
th
Because it must be controlled while up-shifting and downshifting
th
between 4 gear and 5 gear by TCM.
“Turbine speed sensor 1” value becomes zero rpm except 4th gear because of front brake engagement.
In 4th gear, whole rotating members become one unit and the gear ratio will be 1:1 so the turbine
speed sensor 1 and 2 value will be same in 4th gear only.
Also the turbine speed sensor 2 value from
1st to 5th gear is not an actual turbine speed except 4th gear because the rotating member that has a
tone wheel is different from the input shaft. It means that the TCM will calculate the sensed value into
the actual turbine speed by internal coefficient.
Here we can conclude that why there are two turbine speed sensors in this model.
As you can see in
the following illustration, two speeds are different from the real input/turbine speed, as two sensors do
not detect the input shaft directly.
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Turbine
speed
“A”
sensor 2
Turbin
e
speed
Turbine speed sensor
1
1st
2nd
3rd
4th
5th
Anyhow, the sensed speed value from 1st to 5th gear except 4th gear must be converted or calculated
by TCM to be the really actual turbine speed. But it should not be like that in case of 4th gear, because
the sensed value is same as the actual turbine speed. (Whole elements are rotating together with the
gear ratio of 1:1) That is why it is necessary to install one more turbine speed sensor for the 4 th gear
only, that is ‘turbine speed sensor 1’.
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The detecting point of
“Turbine speed sensor 1”
(It rotates at 4th gear only
due to the front brake)
The detecting point of “Turbine speed sensor
2”
(It rotates at every gear (1st, 2nd, 3rd, 4th, 5th)
Input shaft (actual turbine speed must be detected at this point)
The turbine speed will be recognized as 600rpm by TCM, the gear ratio will be decided with the next
gear position before malfunction.
The stand-by learning, 5th gear and the sports mode will be
prohibited.
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Pay attention to the fact that the input speed value has been fixed by 600rpm and the 5th gear is
prohibited in the slide if the turbine speed 1 terminal is shorted to ground.
Pay attention to the fact that the input speed value has been fixed by 600rpm in the slide if the turbine
speed 2 terminal is shorted to ground.
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Pay attention to the fact that the gear is fixed by 4th, if the incorrect gear ratio DTC is set as shown in
the slide. The shown slide is for when the turbine speed sensor 2 was faked (or sensor simulation).
Note:
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2.11 Output Speed Sensor
The Hall IC type digital speed sensor is used to detect the speed of output shaft as shown in the
picture. The output shaft speed is a main factor for the automatic gearshift together with the TPS ratio.
If this sensor is failed, the vehicle speed sensor (‘speedometer’ located in the A/T, see below picture))
will be utilized.
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When this output speed sensor failed, TCM will control the A/T as below.
Stand By Learning control for more smooth shift feeling is inhibited so the severe shift shock can be felt.
5th gear is prohibited.
Sports mode control is prohibited.
However, those two-vehicle speed sensors are failed together (not likely scenario can be occurred), the
gear will be fixed by 4th gear. (Cannot change the gear by sports mode lever operation because the
sports mode control is already being inhibited.)
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2.12 Solenoid valves
Totally seven units of solenoid valves are applied in this automatic transmission.
Every solenoid
valves are linear duty control solenoid valves except low coast brake solenoid valve, which is an ON,
OFF type.
Basically low coast brake is only for engine brake function in 1st or 2nd gear so it is not
necessary to adopt the duty controlled solenoid valve in this brake.
As mentioned in the section of
hydraulic pressure switch, the electrical fault of solenoid valve (short to ground or +B, open circuit) is
detected monitoring the current by TCM.
There is some difference of method depends on the solenoid
valve type.
VFS type solenoid valves: Monitored by current
On/Off type solenoid valve: Monitored by voltage
As in the case of hydraulic pressure switches, there is no solenoid valve for the forward brake and the
reverse brake. The linear solenoid valve is a VFS (Variable force solenoid) valve with higher operating
frequency (about 800Hz) and more fast response, more accurate return stroke than the conventional
duty controlled solenoid valve (62Hz).
As shown on the picture, six units of linear solenoid valves can
be classified into two types. One is “normally high type” and the other one is “normally low type”.
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- Normally high type: Direct, I/C, H&LR clutch solenoid valve
(these have a plug on the cover as in the picture)
- In case of normally high type, the current flow of solenoid valve is high when the TCM does not
control it. That is, normally high current state at the normal condition. At this time, the control
pressure becomes low.
- Normally low type: Line pressure, Lock-up, front brake solenoid valve
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[Solenoid valve schedule depending on the gear position]
Range
P/L
L/U
D/C
Frt/B
P/N
★
H
H
R
★
★
★
D1
★
H
VS
D2
★
★
★
D3
★
★
★
D4
★
★
D5
★
★
★
★
I/C
H&LB/C
LC/B
VS, M
M
★
★
★
★
★
※ H : Hydraulic pressure only applied but not effect the power flow
VS: Operated depending on the vehicle speed.
M: Manual (Sports) mode only
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The ‘slip lock-up’ is not available in this model and the 4th and 5th gear is required for lock up
operation in D range or Sports mode position.
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The 4th gear can be available naturally even if all solenoid valves are off (normally high off or normally
low off) as you can find in the following table.
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2.13 CAN communication
Refer to the following picture for the interface with engine ECM and data link connector.
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2.14 Line pressure checking
Be sure that it is most easy to check the front brake pressure in order to inspect the line pressure,
because the front brake is engaged at all ranges including P, N, D and Reverse range except 4th gear.
[Line pressure]
As the line pressure is increased, the front brake pressure also proportionally rises as shown on the
graph; however it becomes constant value if the line pressure exceeds the value of 1,180kPa. Be sure
that this is not valid in case of 4th gear engagement condition.
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3. Overhaul
The oil pump is supported by ten pieces of bolt on the transmission case. It is composed of the cast
steel and aluminum material and its front portion of the transmission case cannot be separated into two
parts. That is why it is necessary to use an oil pump puller (sliding hammer) to remove the oil pump
from the transmission case. The proper slide hammer can be substituted as an oil pump.
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Accumulators:
Totally three accumulators are built in the valve body that is N-R accumulator (2pcs.) and N-D
accumulator (1pcs.)
There is no accumulator located in the transmission case.
Two pieces of N-R accumulator is installed on the lower valve body and its outlet port is connected to
reverse brake. One piece of N-D accumulator is installed on the upper valve body and its outlet port is
connected to the forward brake, because the forward brake is engaged as soon as the 1st gear is
selected from the neutral range. (N-D control) There are no accumulators for the particular clutch or
brake as in the case of the current AISIN model.
Refer the hydraulic pressure circuit diagram in the
section of appendix on this manual to understand the overall circuit connection.
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4.5
25.6M
10
1125K
2
20K
2M
1M
Increme
LIN
Fits
CAN-C
CAN-B
LIN
ntal
cost
in at
event
masterper
node
the
low
TRANSMISSION
triggered
slaveof
end
dual
fault
single
wire
in wire
car
tolerant
bus
multipl
dual
no
quartz
wire
exing,
making
a LIN
system
a cost
effectiv
e
solution
It is not necessary to remove all bolts for oil strainer in order to remove the valve body assembly from
the transmission case. Just remove 2 bolts (yellow colored ones in the slide)
on the oil strainer and
other 10bolts in the valve body.
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