lock SUZUKI SWIFT 2000 1.G Transmission Service Owner's Manual

7B-8 AUTOMATIC TRANSMISSION (4 A/T)
FAIL SAFE FUNCTION
This function is provided by the safe mechanism that assures safe driveability even when the solenoid valve,
sensor or its circuit fails.
The table below shows the fail safe function for each fail condition of sensor, solenoid or its circuit.
Area Detecting condition Fail safe function
Input/Turbine
speed sensor cir-
cuit
(DTC P0715)Input shaft speed
sensor signal voltage
is too high or too low.When vehicle running and in shift change by automatic elec-
tronic control, gear is fixed to gear which is going to be
selected and lock-up function is turned OFF.
When vehicle running and in no shift change, gear is fixed to
gear right before the trouble occurred and lock-up function is
turned OFF.
When vehicle is at stop after or during detecting trouble, or in
shift change by manual operation while running, gear is fixed
as the followings and lock-up function is turned OFF.
“P” range →
P, “R” range →
R, “N” range →
N,
“D” range →
3rd, “2” range →
2nd, “L” range →
1st Output shaft speed
sensor circuit
(DTC P0720)Output shaft speed
sensor signal voltage
is too high or too low.
Shift solenoid
(DTC P0753)
(DTC P0758)
(DTC P0763)
(DTC P0768)
(DTC P0773)Solenoid output
voltage is too high
although TCM
orders solenoid to
turn off.
Solenoid output
voltage is too low
although TCM
orders solenoid to
turn on.When select lever is “P”, “R”, “N”, “D” or “2” range, A/T sole-
noid power relay is turned OFF and gear is fixed as follows :
“P” range →
P, “R” range →
R, “N” range →
N,
“D” range →
3rd
When select lever is “2” range, gear is fixed to pre pro-
grammed gear position of several patterns as follows :
–Malfunction of No.1 solenoid →
3rd
–Malfunction of No.2 solenoid →
3rd
–Malfunction of No.3 solenoid →
2nd
–Malfunction of No.4 solenoid →
1st or 2nd
–Malfunction of No.5 solenoid →
2nd or 3rd
–Malfunction of 2 or more solenoids →
3rd
When select lever is “L” range, gear is fixed to pre pro-
grammed gear position of several patterns as follows :
–Malfunction of No.1 solenoid →
3rd
–Malfunction of No.2 solenoid →
1st
–Malfunction of No.3 solenoid →
2nd
–Malfunction of No.4 solenoid →
1st or 2nd
–Malfunction of No.5 solenoid →
1st
–Malfunction of 2 or more solenoids →
3rd
TCC circuit
(DTC P0743)Lock-up function is turned OFF.

AUTOMATIC TRANSMISSION (4 A/T) 7B-9
A/T hardware itself
(DTC P0730)Difference in detected
revolution between
input shaft speed
sensor and output
shaft speed sensor is
too wide.“P” range →
P, “R” range →
R, “N” range →
N,
“D”/“2”/“L” range “To be controlled as follows :
1) When detecting trouble at first, gear is selected well-suited
gear calculated with parameters of each sensor’s rev. num-
ber and gear position just when the trouble occurred. Lock-
up function is turned OFF.
2) If A/T can transmit driving force under the above condition,
gear is fixed the selected gear until ignition switch is turned
OFF.
3) If A/T can not transmit driving force under the above condi-
tion, after once vehicle stop, gear which can transmit drive
force is searched one by one until gear is found out. After
gear is found out, position of gear is held until ignition switch
is turned OFF.
Transmission
range sensor cir-
cuit
(DTC P0705)No shift switch signal
is inputted or two or
more shift switch sig-
nals are inputted at
the same time.When vehicle running, shift range position is fixed to shift
range position right before the trouble occurred until vehicle
stop and lock-up function is turned OFF.
When vehicle is at stop after or during detecting the trouble,
gear is fixed as the followings and lock-up function is turned
OFF.
–When 2 adjoining gear position signals are inputted.
“P”, “R” range →
R, “R”, “N” range →
R,
“N”, “D” range →
D, “D”, “2” range →
D,
“2”, “L” range →
2nd
–When 2 or more signals excepting above or no signal are
inputted.
“P” range →
P, “R” range →
R,
“N” range →
N, “D”/“2”/“L” range →
3rd
Transmission tem-
perature sensor cir-
cuit
(DTC P0710)A/T fluid temp. sig-
nal input voltage is
too low.
A/T fluid temp. sig-
nal input voltage
does not go down
although standard
value of engine
rev. signal is input-
ted.When detecting circuit open, TCM control as fluid tempera-
ture is 100°C (212°F).
Lock-up function is turned OFF.
Engine speed input
circuit
(DTC P0725)Inputted engine rev.
signal is too low or
too high.Engine rev. is processed as 4000 rpm.
No compensation or judgement for gear shift control, for
which engine rev. is considered, is processed.
Lock-up function is turned OFF.
Engine coolant
temp./Barometric
pressure signal cir-
cuit
(DTC P1709)No or abnormal
engine coolant temp.
signal is inputtedNo compensation for gear shift control, for which engine cool-
ant temp. and barometric pressure are considered, is pro-
cessed.
Lock -up function is turned OFF. Area Detecting condition Fail safe function

7B-10 AUTOMATIC TRANSMISSION (4 A/T)
CHANGE MECHANISM
The same select pattern shift lever is used as the floor type and
frequently used “N” and “D” ranges are made selectable freely. Throttle position
signal circuit
(DTC P1700)No or abnormal throt-
tle opening signal is
inputtedScheduling of automatic gear shift is performed as throttle
valve opening is 0%.
Control of automatic gear shift (i.e. control of oil pressure) is
performed as throttle valve opening is 100%.
Coast down shifting is performed when brake is applied and
engine rev. is less than 1,500 rpm.
Lock-up function is turned OFF.
Transmission con-
trol system electri-
cal
(DTC P0702)Solenoid power sup-
ply relay output volt-
age is too high
although TCM orders
relay to turn off or
relay output voltage is
too low although TCM
orders relay to turn
on.When relay shorted, the gear is fixed as the followings and
lock-up function is turned OFF.
“P” range →
P, “R” range →
R, “N” range →
N,
“D” range →
3rd, “2” range →
2nd, “L” range →
1st
When relay open, power supply to all solenoids is cut and the
gear is fixed as the followings. Lock-up function is turned
OFF.
“P” range →
P, “R” range →
R, “N” range →
N,
“D”/“2”/“L” range →
3rd
Internal malfunc-
tion of TCM
(DTC P1702)Incorrect calculations
of checking TCM pro-
grammed data indi-
cated.Power supply to all solenoid is cut and the gear is fixed as fol-
lows :
“P” range P, “R” range R, “N” range N,
“D”/“2”/“L” range “3rd Area Detecting condition Fail safe function

AUTOMATIC TRANSMISSION (4 A/T) 7B-11
AUTOMATIC GEAR SHIFT DIAGRAM
Automatic shift schedule as a result of shift control is shown below.
[For 2WD model]
Gear Shift Diagram
TCC Lock-up Diagram
Shift
Throttle opening 1→
22→
33→
44→
33→
22→
1
Full throttle 44 98 - 135 87 35
Closed throttle 13 26 43 34 9 9

7B-12 AUTOMATIC TRANSMISSION (4 A/T)
[For 4WD model]
Gear Shift Diagram
TCC Lock-up Diagram
Shift
Throttle opening 1→
22→
33→
44→
33→
22→
1
Full throttle 40 90 143 124 80 32
Closed throttle 12 24 40 31 9 9

7B-18 AUTOMATIC TRANSMISSION (4 A/T)
TROUBLE DIAGNOSIS TABLE
TABLE 1 (ELECTRICAL)
NOTE:
For the inspection of throttle position sensor, refer to “TP SENSOR” in Section 6E.
Condition Possible Cause Correction
No up-shift
1st
→
→→ → 2nd
2nd
→
→→ → 3rdOutput shaft speed sensor or its circuit faulty Inspect output shaft speed sen-
sor.
Shift solenoid -D (No.4) (1st →
→→ →
2nd), -A
(No.1) (1st →
→→ →
3rd), -E (No.5) (2nd →
→→ →
3rd),
and/or its circuit faultyRepair or replace.
Throttle position sensor or its circuit faulty Inspect TP sensor.
TCM faulty Replace TCM.
3rd
→
→→ → 4th
Output shaft speed sensor or its circuit faulty Inspect output shaft speed sen-
sor.
Shift solenoid -B (No.2), -C (No.3) or its cir-
cuit faultyRepair or replace.
O/D CUT switch circuit faulty Refer to “O/D OFF SWITCH” in
this section and/or inspect its cir-
cuit.
Throttle position sensor or its circuit faulty Inspect TP sensor.
TCM faulty Replace TCM.
No down-shift
4th
→
→→ → 3rd
3rd
→
→→ → 2nd
2nd
→
→→ →1stShift solenoid -C (No.3) (4th →
→→ →
3rd), -D
(No.4) (2nd →
→→ →
1st), -A (No.1) (3rd →
→→ →
2nd), -B
(No.2) (4th →
→→ →
3rd), -E (No.5) (3rd →
→→ →
2nd) or
its circuit faultyRepair or replace.
Throttle position sensor or its circuit faulty Inspect TP sensor.
TCM fault Replace TCM.
Shift point too high or
too lowThrottle position sensor, output shaft speed
sensor or its circuit faultyInspect TP sensor and/or output
shaft speed sensor.
Vehicle does not move
Shift solenoid -A (No.1), -C (No.3), -D (No.4)
or its circuit faultyRepair or replace.
Excessive slip
Shift solenoid -A (No.1) to -E (No.5) or its cir-
cuit faultyRepair or replace.
Excessive shock at
N
→
→→ → D or N
→
→→ → RShift solenoid -A (No.1), -D (No.4), -E (No.5)
or its circuit faultyRepair or replace.
ISC circuit Inspect ISC circuit.
No lock-up or
No lock-up OFFTCC (lock-up) solenoid valve or its circuit
faultyRepair or replace.
Throttle position sensor or its circuit faulty Refer to “THROTTLE POSITION
SENSOR” in Section 6E.
Input shaft speed and/or output shaft speed
sensor or its circuit faulty.Refer to “ECT SENSOR” in Sec-
tion 6E.
Abnormal engine rev. signal or its circuit. Repair or replace.
ECM faulty Inspect ECM.

AUTOMATIC TRANSMISSION (4 A/T) 7B-19
TABLE 2 (MECHANICAL)
Condition Possible Cause Correction
Vehicle does not move
at any rangeManual valve faulty Clean or replace.
Primary regulator valve faulty Clean or replace.
No gear
change
1st
↔
↔↔ ↔ 2nd
Shift solenoid -D (No.4) and/or -E (No.5)
stuck Clean or replace.
2nd
↔
↔↔ ↔ 3rd
Shift solenoid -A (No.1), -C (No.3) and/or fail
valve No.1 stuckClean or replace.
3rd
↔
↔↔ ↔ 4th
Shift solenoid -B (No.2), -C (No.3) and/or fail
valve No.2 stuckClean or replace.
Harsh engagement
P, N
→
→→ → R
Front clutch accumulator faulty Clean or replace.
N
→
→→ → D
1st & 2nd brake accumulator faulty Clean or replace.
1st
→
→→ → 2nd at D
range or 2 rangeFront clutch accumulator faulty Clean or replace.
Shift solenoid -D (No.4) Clean or replace.
2nd
→
→→ → 3rd at D
rangeDirect clutch accumulator faulty Clean or replace.
Shift solenoid -E (No.5) Clean or replace.
3rd
→
→→ → 4th at D
rangeOverdrive brake accumulator faulty Clean or replace.
Shift solenoid -B (No.2) Clean or replace.
All gear change
Primary regulator valve faulty Clean or replace.
Excessive slip
(low line pressure)Primary regulator valve faulty Clean or replace.
Vehicle does not
move at
1st, 2nd, 3rd and
reverse gearRear clutch faulty Repair or replace.
Reverse gear
Reverse brake faulty Repair or replace.
2nd, 3rd and 4th
gearFront clutch faulty Repair or replace.
3rd and 4th gear
Direct clutch faulty Repair or replace.
1st and 2nd gear
1st & 2nd brake faulty Repair or replace.
4th gear
Overdrive brake faulty Repair or replace.
Any forward and
reverse gearParking lock pawl faulty Repair or replace.
Shock or engine stalls
when starting off and
stoppingTCC (lock-up clutch) faulty Inspect and replace as necessary.
TCC (lock-up) solenoid faulty Clean or replace.
Lock-up control valve faulty Clean or replace.
Lock-up signal valve faulty Clean or replace.
No up-shift
1st
→
→→ → 2nd
Front clutch faulty Repair or replace.
2nd
→
→→ → 3rd
Direct clutch faulty Repair or replace.
3rd
→
→→ → 4th
Overdrive brake faulty Repair or replace.
No engine
braking
2nd or 3rd gear
Front, rear or direct clutch or 1st & 2nd brake
faultyRepair or replace
L range 1st gear
Direct clutch or 1st & 2nd brake faulty Repair or replace.
No lock-up
Torque converter clutch faulty Inspect and replace as necessary.
Lock-up control valve faulty Clean or replace.
TCC (lock-up) solenoid faulty Clean or replace.
Secondary regulator valve faulty Clean or replace.
Signal valve faulty Clean or replace.

7B-20 AUTOMATIC TRANSMISSION (4 A/T)
STALL TEST
This test is to check overall performance of automatic transmis-
sion and engine by measuring stall speed at “D” and “R” ranges.
Be sure to perform this test only when transmission fluid is at nor-
mal operating temperature and its level is between FULL and
LOW marks.
1) Apply parking brake and block wheels.
2) Install tachometer.
3) Start engine with select lever shifted to “P”.
4) Depress brake pedal fully.
5) Shift select lever to “D” and depress accelerator pedal fully
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 in “R” range.
8) Stall speed should be within following specification.
Stall speed
: 2,750 – 3,150 r/min CAUTION:
 Do not run engine at stall more than 5 seconds contin-
uously, for fluid temperature may rise excessively
high.
 After performing stall test, be sure to leave engine run-
ning at idle for longer than 30 seconds before another
stall test.
Test result Possible cause
Lower than
standard levelLack of engine output
Defective torque converter
Higher than
standard level
in “D” rangeLow line pressure
Malfunctioning 1st & 2nd brake
Malfunctioning rear clutch
Malfunctioning stator one-way clutch
Higher than
standard level
in “R” rangeLow line pressure
Malfunctioning rear clutch
Malfunctioning reverse brake
Malfunctioning stator one-way clutch
Malfunctioning direct clutch

AUTOMATIC TRANSMISSION (4 A/T) 7B-23
ENGINE BRAKE TEST
1) While driving vehicle in 3rd gear of “D” range, shift select lever down to “2” range and check if engine brake
operates.
2) In the same way as in Step 1), check engine brake for operation when select lever is shifted down to “L”
range.
3) Engine brake should operate in above test.
“P” RANGE TEST
1) Stop vehicle on a slope, shift select lever to “P” range and at the same time apply parking brake.
2) After stopping engine, depress brake pedal and release parking brake.
3) Then, release brake pedal gradually and check that vehicle remains stationary.
4) Depress brake pedal and shift select lever to “N” range.
5) Then, release brake pedal gradually and check that vehicle moves.WARNING:
Before test, make sure that there is no vehicle behind so as to pre-
vent rear-end collision.
Test result Possible cause
Fails to operate when shifted down to “2”
rangeDefective shift switch
1st & 2nd brake defective
Direct clutch defective
Fails to operate when shifted down to “L”
range
WARNING:
Before test, check to make sure no one is around vehicle or
down on a slope and keep watchful for safety during test.
Test result Possible cause
Vehicle moves at “P” range or
remains stationary at “N” rangeDefective parking lock pawl or
spring

7B-28 AUTOMATIC TRANSMISSION (4 A/T)
DTC TABLE
DTC NO.
“O/D OFF” Lamp
Flashing Pattern of DTC
(Not using scan tool)DETECTING ITEMSMIL
Using
scan toolNot using
scan toolVehicle
equipped
with
immobi-
lizer indi-
cator lampVehicle
equipped
without
immobi-
lizer indi-
cator lamp
–12 Normal––
P0715 14Input/Turbine speed sensor circuit
malfunction1 driving
cycleNot
applicable
P0730 18 Incorrect gear ratio2 driving
cyclesNot
applicable
P075321
Shift solenoid-A (No.1) electrical1 driving
cycleNot
applicable
22
P075823
Shift solenoid-B (No.2) electrical1 driving
cycleNot
applicable
24
P0763 43 Shift solenoid-C (No.3) electrical1 driving
cycleNot
applicable
P0768 45 Shift solenoid-D (No.4) electrical1 driving
cycleNot
applicable
P0773 48 Shift solenoid-E (No.5) electrical1 driving
cycleNot
applicable
P074325
Torque converter clutch (lock-up)
system electrical1 driving
cycleNot
applicable
26