shaft SUZUKI SWIFT 2000 1.G Transmission Service Service Manual

AUTOMATIC TRANSMISSION (4 A/T) 7B-7
TRANSMISSION CONTROL MODULE (TCM)
TCM is an electronic circuit component that controls gear shift, idle-up according to the signal from each sensor.
Also it has learning control function for performing optimum control. It is a microcomputer consisting of an IC,
transistor, diode, etc. It is installed behind glove box.
1.“O/D OFF” lamp (in combination meter) 11. Backup lamp 21. Dropping resistor
2.“O/D” off switch 12. Shift indicator (if equipped) 22. Output shaft speed sensor (A/T VSS)
3. Monitor connector No.2 13. A/T 23. Input shaft speed sensor (Turbine rev. sensor)
4. Brake lamp 14. Transmission temperature sensor
(A/T fluid temp. sensor)24. A/T power source relay
5. Brake lamp switch 15. Shift solenoid-A (Shift solenoid No.1) 25. Ignition switch
6. ECM 16. Shift solenoid-B (Shift solenoid No.2) 26. DLC
7. A/C clutch 17. Shift solenoid-C (Shift solenoid No.3) 27. Barometric pressure sensor
8. Transmission range sensor (Shift switch) 18. Shift solenoid-D (Shift solenoid No.4) 28. Solenoid power relay
9. Shift lock solenoid switch (if equipped) 19. Shift solenoid-E (Shift solenoid No.5) 29. Terminal arrangement of TCM coupler
(Viewed from harness side)
10. Shift lock solenoid (if equipped) 20. TCC solenoid (Lock-up solenoid)
C41-14
C41-21
C42-5
C41-23
G02-16
BLKBLKLT GRN/ RED/BLU BLU/ORN
PPL/YEL
3
45
+BB
GRN/WHT
LT BLU
PPL
WHT/BLK
BLK/WHT
BRN
PNK/BLK 6
7
8
C44-8
C43-8
C44-18
C44-20
C43-5
C44-5
910
ORN
RED
GRN/ORN RED/BLK
GRNC43-1
C43-2
C43-3
C43-9
C43-10
C43-11 GRN/YEL
BLU/WHT P
R
N
D
2
L11
12C44-21
C44-17
C43-4
C44-4
12V 12V
12V
12V
12V IG1
IG115V
5VC44-3
C44-16
C44-10
C44-23
C44-24
C44-25
C44-26
C44-22
C44-11
C44-12
C44-13
C43-6
C43-14
C43-13
C43-7
C43-15
C44-2
C44-15
C43-12
BLU BLUBLK
BLK BLK
BLU/YEL
YEL/BLK RED/WHT WHT BLU/ORN RED/BLU GRY/BLU
BLK/YEL WHT/BLU
BRN/WHT BRN/WHT BRN WHT/RED
BLK/YEL
BRN/YEL BLU/RED
GRY/RED13
14
15
16
17
19
20 BRN
21
22
23
+BB 24
25
26
12V
12V
12V
12V
18
12V
IG1
IG11
5V
1
2
28
27

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-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-29
P0741 29Torque converter clutch (lock-up)
solenoid performance or stuck off2 driving
cyclesNot
applicable
P0720 31Output shaft speed sensor circuit
malfunction1 driving
cycleNot
applicable
P170032
Throttle position signal input mal-
function1 driving
cycleNot
applicable
33
P0705 34Transmission range sensor circuit
malfunction1 driving
cycleNot
applicable
P0725 35Engine speed input circuit malfunc-
tion2 driving
cyclesNot
applicable
P071036
Transmission temperature sensor
circuit malfunction2 driving
cyclesNot
applicable
38
P1709 51Engine coolant temperature signal
circuit1 driving
cycleNot
applicable
P0702
52Transmission control system elec-
trical1 driving
cycleNot
applicable
P1702 Internal malfunction of TCMDTC 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

AUTOMATIC TRANSMISSION (4 A/T) 7B-31
DTC P0715 (DTC NO.14) INPUT/TURBINE SPEED SENSOR CIRCUIT MALFUNCTION
1. Input shaft speed sensor 2. TCM coupler (viewed from harness side) 3. TCM
DTC DETECTING CONDITION
Input shaft speed sensor signal voltage too high or too low.
Step Action Yes No
1Was “AUTOMATIC TRANSMISSION DIAGNOSTIC
FLOW TABLE” performed?Go to Step 2. Go to “AUTOMATIC
TRANSMISSION DIAG-
NOSTIC FLOW TABLE”.
2 1) Turn ignition switch OFF and disconnect output shaft
speed sensor – input shaft speed sensor coupler.
2) Measure resistance between terminals of the discon-
nected sensor side coupler.
Is it 160–200 Ω
?
(See figure.)Go to Step 3. Replace input shaft speed
sensor.
3 1) Connect output shaft speed sensor - input shaft
speed sensor coupler then disconnect TCM couplers.
2) Measure resistance between terminal “C43-7” and
“C43-15” of disconnected harness side coupler.
Is it 160–200 Ω
?Go to Step 4.“BLU/YEL” or “RED/WHT”
wire open or shorted each
other.
4 1) Turn ignition switch OFF and connect input shaft
speed sensor coupler then disconnect TCM couplers.
2) Measure resistance between terminal “C43-7” (of dis-
connected harness side coupler) and body ground
then terminal “C43-15” (of disconnected harness side
coupler) and body ground.
Are they about 0 Ω
?
(See figure.)Short in
between “BLU/
YEL” wire and
ground or “RED/
WHT” wire and
ground.Poor connection of termi-
nal “C43-7” or “C43-15” of
TCM.
If all the above are in
good condition, substitute
a known-good TCM and
recheck.

7B-32 AUTOMATIC TRANSMISSION (4 A/T)
Figure for Step 2
Figure for Step 4
1. Output shaft speed sensor - Input shaft speed sensor coupler
2. Input shaft speed sensor terminal

AUTOMATIC TRANSMISSION (4 A/T) 7B-33
DTC P0730 (DTC NO. 18) INCORRECT GEAR RATIO
1. Input shaft speed sensor 4. Shield wire
2. Output shaft speed sensor 5. TCM coupler (viewed from harness side)
3. TCM
DTC DETECTING CONDITION
Difference in detected revolution between input shaft speed sensor and output shaft speed sensor too wide.
Step Action Yes No
1 Check if DTC P0730 (DTC No.18) dis-
played with DTC P0715 (DTC No.14) or
DTC P0720 (DTC No.31).
Is DTC P0730 (DTC No.18) displayed
with DTC P0715 (DTC No.14) or DTC
P0720 (DTC No.31)?
(See figure.)Inspect according to DTC P0715
(DTC No.14) or DTC P0720
(DTC No.31) flow table first.Go to Step 2.
2 1) Turn ignition switch OFF and discon-
nect TCM couplers.
2) Measure resistance between terminal
“C43-13” of the disconnected harness
side coupler and body ground.
Is it about 0 Ω
?
(See figure.)Short in between shield portion
or “BLK” wire and ground.Go to Step 3.

7B-34 AUTOMATIC TRANSMISSION (4 A/T)
Figure for Step 1
Figure for Step 2
Figure for Step 33 Check input shaft speed sensor and out-
put shaft speed sensor referring to each
item in this section.
Are they OK?
(See figure.)Broken wire in shield portion
or broken “BLK” wire, or
shorted to power source cir-
cuit.
Malfunction of A/T itself (over
revolving of C0 clutch drum by
departing of C0 clutch drum
snap ring, clutch slipping, etc.)
If all the above are in good con-
dition, substitute a known-good
TCM and recheck.Inspect and replace
referring to each item in
this section. Step Action Yes No
1. Output shaft speed sensor
2. Input shaft speed sensor

7B-38 AUTOMATIC TRANSMISSION (4 A/T)
DTC P0720 (DTC NO. 31) OUTPUT SHAFT SPEED SENSOR CIRCUIT MALFUNCTION
1. Output shaft speed sensor (A/T VSS) 4. TCM
2. Coupler 5. TCM coupler (viewed from harness side)
3. Shield wire
DTC DETECTING CONDITION
Output shaft speed sensor signal voltage too high or too low.
Step Action Yes No
1 1) Turn ignition switch OFF and disconnect
output shaft speed sensor – input shaft
speed sensor coupler. (See figure.)
2) Measure the resistance between terminals
of disconnected sensor side coupler.
Is it 160 – 200 Ω
?
(See figure.)Go to Step 2. Replace output shaft
speed sensor.
2 1) Connect output shaft speed sensor coupler
then disconnect TCM couplers.
2) Measure resistance between terminal “C43-
6” and “C43-14” of disconnected harness
side coupler.
Is it 160 – 200 Ω
?
(See figure.)Go to Step 3.“WHT” or “BLK” wire open
or shorted each other.