2000 SUZUKI SWIFT clutch

1. PCM
2. Instrument panel
TP sensor
Transmission range sensor
Output shaft speed sensor
(A / T VSS)
Shift solenoid-B
(2nd brake solenoid valve)
Shift solenoid-A
(Direct clutch solenoid valve)PCM
1. Throttle position sensor
2. Throttle body
A: Ground
3. Ground terminal
4. Reference voltage
terminal
5. Output voltage terminal
6. TP sensor
C: Output voltage
(opening angle signal)
D: Power supply from ECM
(reference voltage)
[G10 engine model]
[G13 engine model]
AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC) 7B-7
POWERTRAIN CONTROL MODULE (PCM)
The powertrain control module controls the shift solenoid B (2nd
brake solenoid valve) and the shift solenoid A (direct clutch sole-
noid valve) by sending electric signals to them so as to attain auto-
matic gear shift between the 1st and 2nd gears, and the 2nd and
3rd gears. Equipped as PCM sensed parameters are the throttle
position sensor, transmission range switch and vehicle speed sen-
sor. These switch and sensors sense the throttle valve opening, se-
lector lever’s position and vehicle speed, and send those signals to
the powertrain control module. Then, the powertrain control module
opens and closes valves of the above solenoids according to these
signals. The powertrain control module is installed to the underside
of the instrument panel at the driver’s seat side.
GEAR SHIFT CONTROL SYSTEM
THROTTLE POSITION SENSOR (TP sensor)
The throttle position sensor consisting of a potentiometer is con-
nected to the throttle valve shaft.
Throttle valve opening signal (output voltage) is transmitted from
throttle position sensor to PCM as voltage signal. PCM uses it as
one of the signals to control transmission gear shift.

1. Transmission range sensor
2. Select cable
1. Transmission
2. Shift solenoid-B
(No.2, 2nd brake solenoid valve)
3. Shift solenoid-A
(No.1, direct clutch solenoid valve)
4. Oil strainer
7B-8 AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC)
TRANSMISSION RANGE SENSOR (SHIFT SWITCH)
Being linked with the selector lever, this sensor changes selector
lever positions into electric signals and send them to the engine
control module. The contact points of this sensor for P and N ranges
are also connected with the starting motor circuit.
So when the selector lever is shifted to the P or N range position,
the contact points for P or N range are connected and cause the
starting motor to operate by turning the starter switch ON.
When the selector lever is in any other position than P and N
ranges, the sensor remains OFF and therefore the starting motor
cannot be operated, that is, the engine cannot be started.
Also, as its contact point for R range is connected with the backup
lamp circuit, only when the selector lever is shifted to R range, the
contact point contacts to light the backup lamp.
DIRECT CLUTCH AND 2ND BRAKE SOLENOID
VALVES
These solenoid valves are mounted on the valve body. They are
turned ON and OFF by the signals from the engine control module
and actuate each shift valve (1 – 2 and 2 – 3 valves) so as to control
transmission gear shift.
Shift solenoid-B (2nd brake solenoid valve) operates 1 – 2 shift
valve, and shift solenoid-A (direct clutch solenoid valve) does 2 –
3 shift valve.
OPERATION OF DIRECT CLUTCH AND 2ND BRAKE SOLENOIDS
RangeD2LP, N & R
Gear1st2nd3rd1st2nd1st(2nd)–
Shift solenoid-A (No.1)
(Direct clutch solenoid valve)





Shift solenoid-B (No.2)
(2nd brake solenoid valve)





: Operated (Solenoid Valve is Open)
: Unoperated (Solenoid Valve is Closed)

1. PCM
2. Shift solenoid-A (No.1, Direct clutch solenoid)
3. Shift solenoid-B (No.2, 2nd brake solenoid)
4. Terminal arrangement of PCM coupler
(Viewed from harness side)*1: For G10 engine model
*2: For G13 engine model
7B-26 AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC)
DTC P0753 SHIFT SOLENOID-A (NO.1) ELECTRICAL
DTC P0758 SHIFT SOLENOID-B (NO.2) ELECTRICAL
CIRCUIT DESCRIPTION – Refer to “GENERAL DESCRIPTION” of this section.
DTC DETECTING CONDITION
POSSIBLE CAUSE
Output command from PCM and output voltage do not
agree.DTC P0753:

“G/W” circuit open or short

Shift solenoid-A malfunction

PCM malfunction
DTC P0758:

“G/Or” circuit open or short

Shift solenoid-B malfunction

PCM malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON and warm up engine to normal operating temperature at “P” range.
3) Shift selector lever to “D” range for 1 sec. or longer.
4) Shift it to “P” range and check DTC.

7B-30 AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC)
TABLE A-1 NO STARTING OR SLIPPING IN ANY DRIVE RANGE
STEPACTIONYESNO
1Was “AUTOMATIC TRANSMISSION DIAGNOSTIC
FLOW TABLE” performed?Go to Step 2.Go to
“AUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLE”.
2Is engine rpm at stall test normal?Transmission
failure.Go to Step 3.
3Is engine rpm at stall test too low in any range?Poor engine power or
torque converter
defective.Go to Step 4.
4Is engine rpm at stall test too high only in “D” range?Go to Step 7.Go to Step 5.
5Is engine rpm at stall test too high only in “R” range?Go to Step 9.Go to Step 6.
6Is line pressure proper?Transmission failure.Oil pump defective,
Regulator valve
operation failure,
Throttle valve
operation failure or
Accelerator cable
and oil pressure
control cable
maladjusted.
7Does engine rpm at stall test become normal when
coupler of solenoid valve wire is disconnected?One-way clutch
operation failure.Go to Step 8.
8Is line pressure proper?Forward clutch worn.Oil leak in forward
clutch oil circuit or Oil
leak in “D” range oil
circuit.
9Does engine rpm at stall test become normal when
coupler of solenoid valve wire is disconnected?1st-Reverse brake
worn.Go to Step 10.
10Is line pressure proper?Direct clutch worn.Oil leak in direct
clutch oil circuit or Oil
leak in “R” range oil
circuit.

AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC) 7B-31
TABLE A-2 GEAR CHANGE FAILURE
STEPACTIONYESNO
1Was “AUTOMATIC TRANSMISSION DIAGNOSTIC
FLOW TABLE” performed?Go to Step 2.Go to “AUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLE”.
2Disconnect solenoid valve wire coupler and perform
manual road test.
Is upshift from 1st to 2nd possible?Go to Step 3.1-2 shift valve sticks
or Shift solenoid-B
(2nd brake solenoid)
valve sticks.
3Is upshift from 2nd to 3rd possible?Gear shift control
system defective.
Go to A / T Diagnostic
Flow Table B.2-3 shift valve sticks
or Shift solenoid-A
(Direct clutch
solenoid) valve
sticks.
TABLE A-3 EXCESSIVE SHOCK AT RANGE SELECTION OR GEAR CHANGE
STEPACTIONYESNO
1Was “AUTOMATIC TRANSMISSION DIAGNOSTIC
FLOW TABLE” performed?Go to Step 2.Go to “AUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLE”.
2Is line pressure proper?Go to Step 3.Regulator valve
defective, Throttle
valve defective or
Accelerator cable
maladjusted.
3Does excessive shock occur when selecting “D” range
from “N” range?Forward clutch
accumulator
operation failure,
Forward clutch worn
or Forward clutch oil
circuit check ball
operation failure. Go to Step 4.
4Does excessive shock occur when selecting “R” range
from “N” range?1st-Reverse brake
worn, 1st-Reverse
brake oil circuit check
ball operation failure.Go to Step 5.
5Does excessive shock occur at 1st to 2nd gear
change?2nd brake
accumulator
defective, 2nd brake
worn, 2nd brake oil
circuit check ball
operation failure.In case of excessive
shock at 2nd to 3rd
gear change, Direct
clutch worn or Direct
clutch oil circuit check
ball operation failure.

7B-32 AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC)
STALL TEST
This test is to check overall performance of automatic transmission
and engine by measuring stall speed at D and R ranges.
Be sure to perform this test only when transmission fluid is at normal
operating temperature (70–80C / 158–176F) and its level is be-
tween FULL HOT and LOW HOT. (Refer to “Fluid level” in this sec-
tion.)
CAUTION:
Do not run engine at stall more than 5 seconds continuous-
ly, for oil temperature may rise excessively high.
1) Install tachometer.
2) Apply parking brake and block vehicle wheels.
3) Start engine with selector lever shifted to P range.
4) Depress brake pedal.
5) Shift selector lever to D range and depress accelerator pedal ful-
ly while watching tachometer. Read engine rpm quickly when it
has become constant (stall speed).
6) Release accelerator pedal immediately after stall speed is
checked.
7) In the same way, check stall speed at R range.
8) Stall speed should be within following specification.
Stall speed: 2,500 – 2,900 r / min
(For both G10 and G13 engine models)
9) Possible causes for out-of-specification stall speed are as fol-
lows. Check each part which is suspected to be the cause.
Stall speed measured
Possible causes
Lower than specification
Engine output insufficient

Torque converter defective
Higher than specification in
D range
Forward clutch slippage

One-way clutch defective
Higher than specification in
R range
Direct clutch slippage

1st-reverse brake slippage

1. Drive shaft (LH)
2. Oil pan
7B-34 AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC)
9) Possible causes for out-of-specification line pressure are as
follows. Check each part which is suspected to be the cause.
Line pressure
Possible causes
Higher than specification
in D and R ranges
Regulator valve defective

Throttle valve in valve body
defective

Accelerator cable and oil
pressure control cable
maladjusted
Lower than specification
in D and R ranges
Oil pump defective

Regulator valve defective

Throttle valve in valve body
defective

Accelerator cable and oil
pressure control cable
maladjusted
Lower than specification
only in D range
Forward clutch oil pressure
system oil leakage

D range oil pressure system
oil leakage
Lower than specification
only in R range
Direct clutch oil pressure
system oil leakage

1st-reverse brake oil
pressure system oil leakage

R range oil pressure system
oil leakage
10) Reinstall plug and tighten it to specification.
Tightening Torque
(a): 7.5 N·m (0.75 kg-m, 5.5 lb-ft)

AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC) 7B-35
ROAD TEST
This test is to check if upshift and downshift take place at specified
speeds while actually driving vehicle on a level road.
WARNING:

Carry out the test in very little traffic area to prevent an ac-
cident.

The test requires 2 persons, a driver and a tester.
1) Warm up engine.
2) With engine running at idle, shift selector lever to D range.
3) i) Accelerate vehicle speed by depressing accelerator pedal
very little (within 4 deg. of throttle valve opening).
ii) Check if upshift takes place from 1st to 2nd at about 18 km / h
(11 mile / h) and from 2nd to 3rd at about 30 km / h (19 mile / h).
iii)
[For G10 Engine Model]
Stop vehicle once. Then start it again and while accelerating
by depressing accelerator pedal fully, check if upshift takes
place from 1st to 2nd at 52 km / h (33 mile / h) and from 2nd to
3rd at 97 km / h (61 mile / h).
[For G13 Engine Model]
Stop vehicle once. Then start it again and while accelerating
by depressing accelerator pedal fully, check if upshift takes
place from 1st to 2nd at 58 km / h (36 mile / h) and from 2nd to
3rd at 110 km / h (69 mile / h).
iv) Stop vehicle again.
v) Start vehicle and keep it running at 25 km / h (15 mile / h) and
then release accelerator pedal completely. 1 or 2 seconds lat-
er, depress accelerator pedal fully and check if downshift
from 2nd to 1st takes place.
vi) Keep vehicle running at 75 km / h (47 miles / h) and in the
same way as in step v), check if downshift from 3rd to 2nd
takes place.
vii) If upshift or downshift fails to take place at each specified
speed in the road test, possible causes for such failure are as
follows. Check each part which is suspected to be the cause.
Condition
Possible causes
No upshift from 1st
to 2nd
1 – 2 shift valve defective

2nd brake solenoid valve defective

PCM defective, or disconnection or
poor connection in electric circuit
No upshift from
2nd to 3rd
2-3 shift valve defective

Direct clutch solenoid valve defective

PCM defective, or disconnection or
poor connection in electric circuit
No downshift from
2nd to 1st or 3rd to
2nd
Throttle position sensor defective

PCM defective, or disconnection or
poor connection in electric circuit