speed signal SUZUKI SWIFT 2005 2.G Service Repair Manual

Downloaded from www.Manualslib.com manuals search engine Electronic Stability Program: 4F-5
Yaw rate / G sensor
The yaw rate / G sensor consists of the yaw rate (angular velocity in the vehicle turning direction) sensor and right-left
G (acceleration in right-left direction) sensor and is mounted to the P/S controller B/K at the lower part of the center
console. It detects the angular velocity in the vehicle turn ing direction and movement in the right-left direction, and
then it sends that information to ESP ® control module.
Wheel speed sensor
The vehicle speed is detected by the hall IC type wheel speed sensor (1) and encoder (4). The wheel speed sensor is
fixed to the knuckle and includes a hall IC (3) having 2 hall elements (2).
The encoder consisting of a permanent ma gnet which has S/N electrodes turns inside of the wheel hub along with the
wheel. The wheel speed sensor outputs alternate current.
As the cycle of the alternate current is in proportion to the revolution speed of the encoder, this AC signal (5) is
converted into the voltage signal in the ESP ® control module (6) for detection of the wheel speed.
ESP ® Hydraulic Unit / Control Module
Assembly Description
S7RS0B4601002
ESP ® control module is a component of ESP ® hydraulic
unit / control module assembly and has the following
functions.
Self-Diagnosis Function
ESP ® control module monitors each input and output
signals. When ESP ® control module detects any
malfunction, some of ABS warning lamp (1), EBD
warning lamp (brake warning lamp) (2), ESP ® warning
lamp (3), SLIP indicator lamp (4), ESP ® OFF lamp (5)
are turned ON and indicate the abnormality to driver.
• When ignition switch is turned ON, ABS warning lamp, EBD warning lamp, ESP ® warning lamp, SLIP
indicator lamp and ESP ® OFF lamp light for 2
seconds to check its circuit.
• When no abnormality is detected (the system is in good condition), ABS warning lamp, EBD warning
lamp, ESP ® warning lamp, SLIP indicator lamp and
ESP ® OFF lamp turn OFF after 2 seconds.
• When an abnormality in the system is detected, some of ABS warning lamp, EBD warning lamp (brake
warning lamp), ESP ® warning lamp, SLIP indicator
lamp and/or ESP ® OFF lamp are turned ON and the
area where that abnormality lies is stored in the
memory in ESP ® control module. Fail-Safe Mode
When ESP
® control module detects abnormality, the
system goes into fail-safe mode. And some of functions
of ABS, TCS, stability control system are shut down. For
details of fail safe mode, re fer to “Fail-Safe Table”.
S
N
S
N
S
N
N
S
N
S
12V
2
3
1
5
4
6I7RS0B460003-01
3245
1
I6RS0B460001-01

Downloaded from www.Manualslib.com manuals search engine 4F-6 Electronic Stability Program:
Warning Lamp, Indicator Lamp DescriptionS7RS0B4601003
There are five types of warning lamp and indicator lamp in instrument cluster, which are controlled by ESP ® control
module. They give warning / indication to driver by changing the modes light ON / blinking / light OFF.
The followings are the condition and operation of warning lamps and indicator lamps.
CAN Communication System DescriptionS7RS0B4601004
Refer to “CAN Communication System Description in Section 1A” for CAN communication system description. ESP ®
control module communicates control data with each control module as follows.
ESP ® Control Module Transmission Data
1
245
3
I6RS0B460002-01
1. ESP ® warning lamp 3. ABS warning lamp 5. ESP ® OFF lamp
2. EBD warning lamp (brake warning lamp) 4. SLIP indicator lamp
Warning lamp / Indicator lamp Condition and operation
ABS warning lamp If ABS has abnor mality, the lamp turns “ON”.
EBD warning lamp (brake warning
lamp) • If EBD system has abnormality, the lamp turns “ON”.
• If bake fluid level in reservoir is lower
than minimum level, the lamp turns “ON”.
• Parking brake switch is ON, the lamp turns “ON”.
ESP ® warning lamp If ESP ® systems has abnormality, the lamp turns “ON”.
SLIP indicator lamp • If stability cont rol system and traction control system is active, the lamp blinks
at 5 Hz.
• If Steering angle sensor calibration is incompleted, the lamp blinks at 1 Hz.
ESP ® OFF lamp • If ESP ® OFF switch is turned “ON”, the ESP ® OFF lamp light up. When it is
“ON”, TCS and stability control system functions are controlled not to work.
• ESP® OFF lamp light up to indicate th at brake control of traction control
function is controlled not to act if brake pad temperature is over 320 °C (608 °F)
and any of wheel is in wheel spin condition.
Combination
meter
Transmit DATA
ESP® control
moduleECMSteering angle sensor
Torque request signal
Wheel speed signal (front right)
Wheel speed signal (front left)
ESP® status signal
ABS active signal
ABS indication signal
EBD indication signal
Steering angle neutral position
I7RS0B460004-01

Downloaded from www.Manualslib.com manuals search engine Electronic Stability Program: 4F-7
ESP® Control Module Reception Data
CAN Communication System For Electronic Stability Program DescriptionS7RS0B4601005
There is CAN communication system only for ESP ® control module (1) and yaw rate / G sensor assembly (2).
This CAN communication system is independent from other control modules.
ESP ® communicates control data with yaw rate / G sensor assembly as follows.
ESP ® Transmission Data to Yaw Rate / G Sensor Assembly
• Longitudinal G neutral position
• Lateral G neutral position
ESP ® Reception Data from Yaw Rate / G Sensor Assembly
• Vehicle yaw rate signal
• Vehicle longitudinal G signal
• Vehicle lateral G signal
• Yaw rate / G sensor assembly related malfunction
BCM
Receive DATA
ESP® control
moduleECMSteering angle sensor
Engine torque signal
Accelerator pedal position signal
Engine speed signal
Brake pedal switch signal
Brake fluid level switch signal
Parking brake switch signal
Steering angle signal
Steering angle sensor related malfunction
I7RS0B460005-01
2 1
I6JB01460006-01

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EBD Warning Lamp (Brake Warning Lamp)
Check
S7RS0B4604047
NOTE
Perform this check on a level place.

1) Turn ignition switch ON with parking brake applied.
2) Check that EBD warning lamp (brake warning lamp)
(1) is turned ON.
3) Release parking brake with ignition switch ON and check that EBD warning lamp (brake warning lamp)
goes off.
If it doesn't go off, go to “EBD Warning Lamp (Brake
Warning Lamp) Comes ON Steady”.
DTC CheckS7RS0B4604004
1) Turn ignition switch to OFF position.
2) Connect SUZUKI scan tool to data link connector (1).
Special tool
(A): SUZUKI scan tool
3) Turn ignition switch to ON position.
4) Read DTC according to instructions displayed on
SUZUKI scan tool and print it or write it down. Refer
to SUZUKI scan tool operator’s manual for further
details.
NOTE
If SUZUKI scan tool can not communicate
ESP® control module, perform “Serial Data
Link Circuit Check”.

5) After completing the check, turn ignition switch off and disconnect SUZUKI scan tool from DLC.
DTC TableS7RS0B4604005
CAUTION!
Be sure to perform “Electronic Stability Program System Check” before starting diagnosis.

BRAKE
1
I4RS0A450008-01
(A)
1
I4RS0B450003-01
DTC (displayed
on SUZUKI scan tool) Diagnostic Items
Detecting condition (DTC will
beset when detecting) ABS
warning lamp EBD
warning lamp ESP
®
warning lamp
NO DTC Normal — — — —
) C1016 Stop lamp switch failure Vehicle behavior and stop lamp
switch signal is disagreed for
specified time.———
) C1017 Lateral G sensor range /
performance Lateral G sensor signal is out of
specified range.
——
{
) C1018 Brake fluid level switch
failure • Brake fluid level is too low.
• Input signal of brake fluid level
switch to BCM is low level. ——
{
) C1020 Master cylinder pressure
sensor power supply failure Power supply volt
age to master
cylinder pressure sensor in ESP ®
hydraulic unit / control module
assembly is out of specification. ——
{
) C1021 Right-front wheel speed
sensor circuit failure Wheel sensor signal is out of
specified range.
{
*1 {

Downloaded from www.Manualslib.com manuals search engine 4F-16 Electronic Stability Program:
) C1022 Right-front wheel speed
sensor or encoder failure Abnormal wheel speed sensor
signal is detected.
{
*1 {
) C1023 Yaw rate sensor failure • Yaw rate sensor signal is out of
range.
• Vehicle behavior and yaw rate signal is disagreed. ——
{
) C1024 Steering angle sensor circuit
failure • Steering angle sensor internal
defect is detected by CPU in
steering angle sensor.
• Steering angle sensor signal is out of specified range. ——
{
) C1025 Left-front wheel speed
sensor circuit failure Wheel sensor signal is out of
specified range.
{
*1 {
) C1026 Left-front wheel speed
sensor or encoder failure Abnormal wheel speed sensor
signal is detected.
{
*1 {
) C1027 ESP
® OFF switch circuit
failure Mechanical switch failure, failure in
switch wiring is shorted to ground.
———
) C1028 Master cylinder pressure
sensor circuit failure Input signal voltage from master
cylinder pressure sensor in ESP
®
control module is too high or low. ——
{
) C1031 Right-rear wheel speed
sensor circuit failure Wheel sensor signal is out of
specified range.
{
*1 {
) C1032 Right-rear wheel speed
sensor or encoder failure Abnormal wheel speed sensor
signal is detected.
{
*1 {
) C1034 Yaw rate / G sensor
assembly power supply
failure Power supply voltage of yaw rate /
G sensor assembly is too high when
ignition switch OFF.
——{
Power supply voltage of yaw rate /
G sensor assembly is too low when
ignition switch ON.
) C1035 Left-rear wheel speed
sensor circuit failure Wheel sensor signal is out of
specified range.
{
*1 {
) C1036 Lef

t-rear wheel speed
sensor or encoder failure Abnormal wheel speed sensor
signal is detected.
{
*1 {
) C1037 Steering angle sensor power
supply failure Power supply voltage to steering
angle sensor is too low.
——
{
) C1038 Steering angle sensor detect
rolling counter failure from
ESP
® control module ESP
® control module rolling
counter failure is detected by
steering angle sensor. ——
{
) C1039 Yaw rate / G sensor
assembly internal failure Yaw rate / G sensor assembly
internal failure is detected.
——
{
) C1040 Stability control system
function failure Stability control is active for more
than specified time
without yaw rate
change. ——
{
DTC (displayed
on SUZUKI scan tool) Diagnostic Items
Detecting condition (DTC will
beset when detecting) ABS
warning lamp EBD
warning lamp ESP
®
warning lamp

Downloaded from www.Manualslib.com manuals search engine 4F-20 Electronic Stability Program:
NOTE
•{: Activated
• X: Deactivated
• *1: If two or more wheel speed sensor are defective, ABS warning lamp, EBD warning lamp and ESP ® warning lamp are lit and all the control functions are deactivated. If one wheel speed sensor is
defective, ABS warning lamp and ESP ® warning lamp are lit and ABS and TCS / stability control are
deactivated.
• *2: ESP ® OFF mode is cancelled and all control functions are activated.
• *3: EBD control function is activated only if po wer supply circuit is little low voltage malfunction.

Scan Tool DataS7RS0B4604024
The parameter data below are values measured with the scan tool when the normally operating vehicle is under the
following conditions. When taking measurements for comparis on by using the scan tool, be sure to check that the
vehicle is under the following conditions.
• Apply parking brake and block wheels.
• Ignition switch ON.
• Turn OFF air conditioning (if equipped).
• Set the wheel in straight-ahead position and hands off steering wheel.
• Turn OFF all electric loads (except ignition).
• Check that there is no DTC.
Scan Tool Data Definition
Battery Volt (V): Battery Voltage is an analog input
signal read by the ESP ® control module. Certain
ESP ® control module functions will be modified if the
battery voltage falls below or rises above
programmed thresholds.
Pump Motor Driver (V): This parameter indicates the
operational condition of the pump motor driver
(transistor).
RF Wheel Speed, LF Wheel Speed, RR Wheel Speed and LR Wheel Speed (km/h, MPH): Wheel speed
is ESP ® control module internal parameter. It is
computed by reference puls es from the wheel speed
sensor. Brake Switch (ON, OFF):
This switch signal informs
the ESP ® control module whether the brake is active
or not.
Master Cyl Press (MPa): Brake fluid pressure from
brake master cylinder.
G Sensor (lateral) (G): Lateral acceleration is
measured by yaw rate / G sensor assembly and
output to ESP ® control module by pulse signal.
Yaw rate sensor (Deg/s): Yaw rate sensor is measured
by yaw rate / G sensor assembly and output to
ESP® control module by pulse signal.
Steering angle Sen ( °): Steering wheel rotation angle
is measured by steering angle sensor and output to
ESP® control module by pulse signal.
Scan Tool Data Standards Condition
Battery Voltage 10.0 – 16.0 V —
Pump Motor Driver 0.0 V —
RF Wheel Speed 0 km/h, 0.0 MPH Veh icle is in stationary condition.
LF Wheel Speed 0 km/h, 0.0 MPH Veh icle is in stationary condition.
RR Wheel Speed 0 km/h, 0.0 MPH Vehic le is in stationary condition.
LR Wheel Speed 0 km/h, 0.0 MPH Veh icle is in stationary condition.
Brake Switch ON Brake pedal is depressed
OFF Brake pedal is released
Master Cyl Press 0 ± 0.8 MPa Brake pedal is released
G Sensor (lateral) 0 ± 0.1 G Vehicle is on the level
Yaw rate sensor 0 ± 4 deg/s Vehicle is on the level
Steering angle Sen 0 ± 3 ° Front wheels are in straight-ahead
position
Stability control INACTIVE Stability control system is not working
TCS control (brake) INACTIVE Brake function by TCS is not working
TCS control (engine) INACTIVE Torque control by TCS is not working
ESP ® off state (cont) ESP®
ON ESP
® OF
F switch is OFF condition
ESP® OFF ESP ® OFF switch is ON condition
Steering angle Sen Neutral Front wheels are in straight-ahead
position

Downloaded from www.Manualslib.com manuals search engine 4F-32 Electronic Stability Program:
DTC C1021, C1022 / C1025, C1026 / C1031, C1032 / C1035, C1036: Wheel Speed Sensor Circuit or
Encoder Failure
S7RS0B4604051
DTC C1021 / C1025 / C1031 / C1035: Right-Front / Left-Front / Right-Rear / Left-Rear Wheel Speed
Sensor Circuit Failure
DTC C1022 / C1026 / C1032 / C1036: Right-Front / Left-Front / Right-Rear / Left-Rear Wheel Speed
Sensor or Encoder Failure
Wiring Diagram
DTC Detecting Condition and Trouble Area
NOTE
When the vehicle was operated in any of the following ways, one of these DTCs may be set even when
the sensor is in good condition. If such possibility is suspected, clear DTC once referring to “DTC
Clearance” and then performing the driving test as described in Step 2 of “Electronic Stability Program
System Check”, check whether or not any abnormality exists.
• The vehicle was driven with parking brake pulled.
• Wheel spin occurred while driving.
• Wheel(s) was turned while the vehicle was jacked up.
• The vehicle was stuck.

DTC Troubleshooting
[A]E85
161
15
2
3
4
5
6
7
8
9
10
11
12
13
14
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
3233
34
35
36
37
38
39
40
41
42
43
44
45
46
47
RED/BLKRED E85-15 E85-14
12V
BLKWHT
1
WHT/BLKWHTE85-2 E85-3
12V
BLKWHT
2
BLKWHTLT GRN/BLKLT GRNE85-6 E85-5
12V
3
BLKWHTBRNE85-11 E85-12
12V
4YEL 5
I6RS0B460016-01
[A]: ESP
® control module connector (viewed from
terminal side) 2. Right- front wheel speed sensor 4. Right-rear wheel speed sensor
1. Left-front wheel speed sensor 3. Left-rear wheel speed sensor 5. ESP ® hydraulic unit / control module assembly
DTC Detecting Condition Trouble Area
DTC C1021, C1025, C1031, C1035:
Wheel sensor signal is out of specified range.
DTC C1022, C1026, C1032, C1036:
Abnormal wheel speed sensor signal is detected. • Wheel speed sensor
• Wheel speed sensor circuit
• Wheel encoder
• ESP
® control module
Step Action YesNo
1 Was “Electronic Stability Pr ogram Check” performed? Go to Step 2.Go to “Electronic
Stability Program
System Check”.

Downloaded from www.Manualslib.com manuals search engine 4F-34 Electronic Stability Program:
DTC C1024: Steering Angle Sensor Circuit FailureS7RS0B4604029
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC C1027: ESP® OFF Switch Circuit FailureS7RS0B4604030
Wiring Diagram 6
Check wheel speed sensor
1) Refer to “Front / Rear Wheel Speed Sensor On-Vehicle
Inspection”, check output voltage or waveform.
Is specified voltage and/or waveform obtained? Substitute a known-
good ESP
® hydraulic
unit / control module
assembly and recheck. Replace wheel speed
sensor and recheck.
Step
Action YesNo
DTC Detecting Condition Trouble Area
• Steering angle sensor internal defect is detected by CPU in steering angle sensor.
• Steering angle sensor signal is out of specified range. • Steering angle sensor
• ESP
® control module
Step Action YesNo
1 Was “Electronic Stability Pr ogram Check” performed? Go to Step 2.Go to “Electronic
Stability Program
System Check”.
2 DTC check for ESP®
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ignition switch ON and check DTC for ESP ®.
Are DTC U1073 and/or U1126 detected? Go to applicable DTC
diag. flow.
Go to Step 3.
3 Check sensor calibration
1) Calibrate steering angle sensor referring to “Sensor
Calibration”.
2) Clear all DTC(s) and check DTC for ESP ®.
Is DTC C1024 still detected? Go to Step 4.
Steering angle sensor
calibration was
incompleted.
4 Check steering angle sensor
1) Check steering angle sensor referring to “Steering Angle
Sensor On-Vehicle Inspection”.
Is it good condition? Substitute a known-
good ESP
® hydraulic
unit / control module
assembly and recheck. Replace steering angle
sensor.
[A]
E85
161
15
2
3
4
5
6
7
8
9
10
11
12
13
14
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
3233
34
35
36
37
38
39
40
41
42
43
44
45
46
47
LT GRN/REDBLK/ORN
12V
E85-7
1 2
I6RS0B460018-01
[A]: ESP
® control module connector (viewed from terminal side) 1. ESP ® OFF Switch 2. ESP ® hydraulic unit control module assembly

Downloaded from www.Manualslib.com manuals search engine Table of Contents 5- i
5
Section 5
CONTENTS
Transmission / Transaxle
Precautions ................................................. 5-1
Precautions............................................................. 5-1
Precautions on Transmission / Transaxle ............. 5-1
Automatic Transmission/Transaxle ....... 5A-1
Precautions........................................................... 5A-1Precautions in Diagnosing Trouble ..................... 5A-1
Precautions for Disassembly and Reassembly ...................................................... 5A-1
General Description ............................................. 5A-3 A/T Description ................................................... 5A-3
Clutch / Brake / Planetary Gear Function of Automatic Transaxle ......................................... 5A-6
Table of Component Operation ........................... 5A-7
Brake Interlock System Construction .................. 5A-8
A/T Diagnosis General Description ..................... 5A-8
On-Board Diagnostic System Description ........... 5A-8
CAN Communication System Description........... 5A-9
Schematic and Routing Diagram ...................... 5A-10 Transmission Control Module (TCM) Wiring
Diagram .......................................................... 5A-10
Automatic Gear Shift Table ............................... 5A-12
Component Locatio n ......................................... 5A-13
Electronic Shift Cont rol System Components
Location .......................................................... 5A-13
Diagnostic Information and Procedures .......... 5A-15 A/T System Check ............................................ 5A-15
Visual Inspection ............................................... 5A-18
Malfunction Indicator Lamp (MIL) Check .......... 5A-18
Transmission Warning Ligh t Check .................. 5A-18
DTC Table ......................................................... 5A-19
DTC Check ....................................................... 5A-20
DTC Clearance ................................................. 5A-20
Fail-Safe Table ................ .................................. 5A-21
Scan Tool Data ................................................. 5A-23
A/T Basic Check ............................................... 5A-26
Road Test ......................................................... 5A-27
Manual Road Test ........... .................................. 5A-29
Engine Brake Test ............................................ 5A-30
Stall Test ........................................................... 5A-30
Time Lag Test ................................................... 5A-31
Line Pressure Test .......... .................................. 5A-32
“P” Range Test.................................................. 5A-33
A/T Symptom Diagnosis ..... .............................. 5A-34 No Gear Shift to 4th gear .................................. 5A-41
No Lock-Up Occurs ........................................... 5A-42
Transmission Warning Light Circuit Check –
Light Does Not Come “ON” at Ignition Switch
ON ................................................................... 5A-43
Transmission Warning Light Circuit Check – Light Remains “ON” at Ignition Switch ON ...... 5A-43
DTC P0602: Control Module Programming Error ................................................................ 5A-44
DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL input) .................. 5A-44
DTC P0707: Transmission Range Sensor Circuit Low ...................................................... 5A-46
DTC P0712: Transmission Fluid Temperature Sensor “A” Circuit Low ... ................................. 5A-48
DTC P0713: Transmission Fluid Temperature Sensor “A” Circuit High .. ................................. 5A-49
DTC P0717: Input / Turbine Speed Sensor “A” Circuit Malfunction........................................... 5A-51
DTC P0722: Output Speed Sensor Circuit No Signal .............................................................. 5A-52
DTC P0787: Shift / Timing Solenoid Low .......... 5A-54
DTC P0788: Shift / Timing Solenoid High ......... 5A-56
DTC P0961: Pressure Control Solenoid “A”
Control Circuit Range / Performance .............. 5A-58
DTC P0962: Pressure Control Solenoid “A”
Control Circuit Low .......................................... 5A-60
DTC P0963: Pressure Control Solenoid “A”
Control Circuit High ......................................... 5A-62
DTC P0973 / P0976: Shift Solenoid “A” Control Circuit Low / Shift Solenoid “B”
Control Circuit Low .......................................... 5A-64
DTC P0974 / P0977: Shift Solenoid “A” / Shift Solenoid “B” Control Circuit High .................... 5A-66
DTC P1702: Internal Co ntrol Module Memory
Check Sum Error............................................. 5A-68
DTC P1703: Can Invalid Data - TCM ................ 5A-68
DTC P1723: Range Select Switch Malfunction ...................................................... 5A-69
DTC P1774: CAN Communication Bus Off ....... 5A-71
DTC P1777: TCM Lost Communication with ECM (Reception Error).................................... 5A-73
DTC P1778: TCM Lost Communication with BCM (Reception Error).................................... 5A-74

Downloaded from www.Manualslib.com manuals search engine Automatic Transmission/Transaxle: 5A-3
General Description
A/T DescriptionS7RS0B5101001
This automatic transaxle is electronic control full automatic transaxle with forward 4-speed and reverse 1-speed.
The torque converter is a 3-element, 1-step and 2-phase type and is equipped with an automatically controlled lock-up
mechanism.
The gear change device consists of a ravigneau type planet ary gear unit, 3 multiple disc type clutches, 3 multiple disc
type brakes and 2 one-way clutches.
The hydraulic pressure control device consists of a valve body assembly, pressure control solenoid valve (linear
solenoid), 2 shift solenoid va lves, TCC pressure control solenoid valve (lin ear solenoid) and a timing solenoid valve.
Optimum line pressure complying with engine torque is produced by the pressure control solenoid valve in
dependence upon control signal from transmission control module (TCM). This makes it possible to control the line
pressure with high accuracy in accordance with the engine power and running conditions to achieve smooth shifting
characteristics and high efficiency.
A clutch-to-clutch control system is prov ided for shifting between 3rd gear and 4th gear. This clutch-to-clutch control
system is made to function optimally , so that hydraulic pressure controls such as shown below are conducted.
• When upshifting from 3rd gear to 4th gear, to adjust the drain hydraulic pressure at releasing the forward clutch, a
timing solenoid valve is used to switch a hydraulic passage with an orifice to another during shifting.
• When downshifting from 4th gear to 3rd gear, to adjust the line pressure applied to the forward clutch at engaging the forward clutch, a timing solenoid valve is used to s witch a hydraulic passage with an orifice to another during
shifting.
• When upshifting from 3rd gear to 4th gear with engine throttle opened, to optimize the line pressure applied to the forward clutch at releasing the forward clutch, the learning control is processed to compensate the switching timing
of the timing solenoid at every shifting.
• When downshifting from 4th gear to 3rd gear with engine throttle opened, to optimize the line pressure applied to
the forward clutch at engaging the forw ard clutch, the learning control is processed to compensate the line pressure
at every shifting.
Employing the ravigneau type planetary gear unit and this clutch-to-clutch control system greatly simplifies the
construction to make possible a lightweight and compact transaxle.
A line pressure learning control is conducted to provide opti mum shifting time at every upshifting with engine throttle
opened. If long upshifting time is detected, the subsequent line pressure applied during upshifting is intensified. On the
contrary, if short upshifting time is detected, the subs equent line pressure applied during upshifting is weakened.
Slip controlled lock-up function
Even at a lower speed than when the TCC gets engaged completely, control over the TCC pressure control solenoid
works to cause the TCC to slip (be engaged slightly), ther eby improving the transmission efficiency. While such slip
control is being executed, the oil pressure applied to the TCC is controlled by the TCC pressure control solenoid so
that the difference between the engine speed and the input shaft speed becomes close to the specified value.
Also, during deceleration, the TCC is made to slip (be enga ged slightly) to raise the engine speed and enlarge the fuel
cut operation range so that better fuel consumption is achieved.
Due to this reason, it is absolutely necessary for the automati c transmission to use ATF suitable for slip control. Use of
any fluid other than the specified ATF may cause j uddering or some other faulty condition to occur.