7B1-16 AUTOMATIC TRANSMISSION (4 A/T)
GEAR SHIFT
Trouble Diagnosis Table 3
TRANSMISSION FLUID
RUNNING CONDITION
Condition Possible Cause Correction
Poor 1–2 shift, exces-
sive slippageRegulator valve sticking Replace.
1–2 shift valve sticking Replace.
Shift solenoid valve-B sticking Replace.
Intermediate coast modulator valve sticking Replace.
Poor 2–3 shift, exces-
sive slippage2–3 shift valve sticking Replace.
Shift solenoid valve-A sticking Replace.
Poor start or surging
in “D” rangeRegulator valve sticking Replace.
Poor 3-4 shift, exces-
sive slippage3–4 shift valve sticking Replace.
Shift solenoid valve-B sticking Replace.
Excessive shock on
1–2 shiftRegulator valve sticking Replace.
Faulty accumulator, second brake piston Replace.
Excessive shock on
2–3 shiftRegulator valve sticking Replace.
Faulty accumulator, direct clutch piston Replace.
Excessive shock on
3–4 shiftRegulator valve sticking Replace.
Non operate lock-up
systemTCC (Lock-up) control valve sticking Replace.
Solenoid valve No.2 (TCC solenoid valve) stick-
ingReplace.
Condition Possible Cause Correction
Low fluid pressureLeakage from oil pressure circuit Overhaul.
Condition Possible Cause Correction
Unable to run in all
rangeWear in oil pump Replace.
Seizure in oil pump Replace.
Fluid pressure leakage to over drive clutch due
to wear of oil pump bushingReplace.
Faulty in torque converter Replace.
Poor 1st speed run-
ning or excessive slip-
page in “D” or “2”Fluid pressure leakage from forward clutch due
to wear or breakage of O/D case seal ringReplace.
Overdrive clutch slipping Replace.
Unable to run or
excessive slippage in
“L” rangeFluid pressure leakage of forward clutch due to
wear or breakage of O/D case seal ringReplace.
Reverse brake disc slipping Replace.
Broken brake piston O-ring Replace.
Unable to run or
excessive slippage in
“R” rangeFluid pressure leakage to direct clutch due to
wear or breakage of center support seal ringReplace.
Worn direct clutch Replace.
AUTOMATIC TRANSMISSION (4 A/T) 7B1-17
GEAR SHIFT
ABNORMAL NOISE
Scan Tool Data
Refer to Section 6-1.
Inspection of PCM and Its Circuit
Refer to Section 6-1.
Wire Harness and Connectors
Refer to Section 6-1.Condition Possible Cause Correction
Poor 1–2 shift, exces-
sive slippageFluid pressure leakage to overdrive clutch due
to wear or breakage of O/D case seal ringReplace.
Faulty second brake Replace.
Broken O-ring of second brake piston Replace.
Faulty second coast brake (in “2” range) Replace.
Poor 2–3 shift, exces-
sive slippageFluid pressure leakage to overdrive clutch due
to wear or breakage of O/D case seal ringReplace.
Worn direct clutch bushing Replace.
Direct clutch slipping Replace.
Foreign material caught in direct clutch piston
check ballReplace.
Poor start or surging
in “D” rangeFluid pressure leakage of forward clutch due to
wear or breakage of O/D case seal ringReplace.
Malfunction of forward clutch Replace.
Poor 3–4 shift, exces-
sive slippageFaulty overdrive brake Replace.
Faulty overdrive clutch Replace.
Poor start or juddering
in “R” rangeFluid pressure leakage of direct clutch due to
wear or breakage of oil center support seal ringReplace.
Worn direct clutch Replace.
Excessive shock on
1– 2 shiftFaulty one-way clutch Replace.
Non operate lock-up
systemFaulty torque converter Replace.
Condition Possible Cause Correction
Abnormal noise in “P”
or “N” rangeWorn oil pump Replace.
7B1-22 AUTOMATIC TRANSMISSION (4 A/T)
Table B-1 : “O/D OFF” Light Circuit Check (“O/D OFF” Light Doesn’t Light at
Ignition Switch ON But Engine Starts Up)
WIRING DIAGRAM
TROUBLESHOOTING
1. PCM 4. P/N change switch
2. Fuse 5. J/C
3. O/D off switch 6. J/C
Step Action Yes No
1“O/D OFF” light circuit check:
1) With ignition switch OFF, disconnect cou-
plers from PCM.
2) Using service wire, connect E61-20 termi-
nal of disconnected PCM coupler and
ground.
Does “O/D OFF” light turn ON at ignition switch
ON?Poor E61-20 terminal con-
nection.
If OK, substitute a know-
good PCM and recheck.Bulb burned out or faulty
“WHT/BLK”, “BLK/WHT”
wire.
7B1-24 AUTOMATIC TRANSMISSION (4 A/T)
Table B-3 : “POWER” Light Circuit Check (“POWER” Light Doesn’t Light at
Ignition Switch ON But Engine Starts Up)
WIRING DIAGRAM
TROUBLESHOOTING
1. PCM 4. P/N change switch
2. Fuse 5. J/C
3. O/D off switch
Step Action Yes No
1“POWER” light circuit check :
1) With ignition switch OFF, disconnect cou-
plers from PCM.
2) Using service wire, connect E61-21 termi-
nal of disconnected PCM coupler and
ground.
Does “POWER” light turn ON at ignition switch
ON?Poor E61-21 terminal con-
nection.
If OK, substitute a known-
good PCM and recheck.Bulb burned out or faulty
“GRY/BLU”, “BLK/WHT”
wire.
AUTOMATIC TRANSMISSION (4 A/T) 7B1-27
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC, pending DTC and freeze frame data in PCM memory by using scan tool and start engine.
3) Shift A/T selector lever to each of L, 2, D, N, R and P ranges for 30 seconds each.
4) Increase vehicle speed to about 70 km/h (45 mile/h) in D range.
5) Keep driving above vehicle speed for 30 seconds.
6) Release accelerator pedal, decrease vehicle speed and stop vehicle.
7) Check DTC and/or pending DTC.
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester, on a level road.
Step Action Yes No
1Was “A/T DIAGNOSTIC FLOW TABLE” in this section
performed?Go to Step 2. Go to “A/T DIAGNOS-
TIC FLOW TABLE” in
this section.
2 Do you have SUZUKI scan tool? Go to Step 3. Go to Step 4.
3 Check Transmission range switch (sensor) circuit for
operation.
Check by using SUZUKI scan tool :
1) Connect SUZUKI scan tool to DLC with ignition
switch OFF.
2) Turn ignition switch ON and check transmission
range signal (P, R, N, D, 2 or L) on display when
shifting select lever to each range.
Is applicable range indicated?
Are check results satisfactory?Intermittent trouble.
Check for intermittent
referring to “INTER-
MITTENT AND POOR
CONNECTION” in
Section 0A.Go to Step 5.
4 Check Transmission range switch (sensor) circuit for
operation.
Check by not using SUZUKI scan tool :
1) Turn ignition switch ON.
2) Check voltage at terminals C51-1-6, C51-1-7,
C51-1-18, C51-1-19, C51-1-27 and C51-1-28
respectively with select lever shifted to each
range.
Taking terminal C51-1-28 as an example, is battery
voltage indicated only when select lever is shifted to
“2” range and 0 V for other ranges as shown in figure?
Check voltage at other terminals likewise, referring to
figure.
Are check results satisfactory?Intermittent trouble.
Check for intermittent
referring to “INTER-
MITTENT AND POOR
CONNECTION” in
Section 0A.Go to Step 5.
5 Check select cable for adjustment referring to
“SELECT CABLE ADJUSTMENT” in this section.
Is it adjusted correctly?Go to Step 6. Adjust.
7B1-30 AUTOMATIC TRANSMISSION (4 A/T)
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC, pending DTC and freeze frame data by using scan tool.
3) Start engine and turn O/D cut switch ON.
4) Shift select lever to D range and start vehicle.
5) Keep vehicle speed at higher than 10 km/h (7 mile/h) with 1st gear in D range for 2 sec. or more.
6) Increase vehicle speed and keep it at higher than 20 km/h (13 mile/h) with 2nd gear in D range for 2 sec. or
more.
7) Increase vehicle speed and keep it at higher than 30 km/h (20 mile/h) with 3rd gear in D range for 2 sec. or
more.
8) Stop vehicle.
9) Check DTC and/or pending DTC.
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester, on a level road.
Step Action Yes No
1Was “A/T DIAGNOSTIC FLOW TABLE” in this
section performed?Go to Step 2. Go to “A/T DIAGNOSTIC
FLOW TABLE” in this sec-
tion.
2 Input shaft speed sensor circuit check :
1) Remove PCM cover.
2) With ignition switch OFF, disconnect PCM
connectors.
3) Check for proper connection to input shaft
speed sensor at C51-1-10 and C51-1-11
terminals.
4) If OK, check resistance of sensor circuit.
Input shaft speed sensor resistance :
Resistance between C51-1-10 and C51-1-11
530 – 650 Ω
ΩΩ Ω (at 20 °C (68 °F))
Resistance between C51-1-10/C51-1-11 and
ground :
1 MΩ
ΩΩ Ω or more
Are check results satisfactory?Go to Step 4. Go to Step 3.
3 Input shaft speed sensor check :
1) With ignition switch OFF, disconnect input
shaft speed sensor connector.
2) Check for proper connection to input shaft
speed sensor at each terminals.
3) If OK, then check resistance of input shaft
speed sensor.
Are measured values as specified in Step 2?“BLU/GRN” or “BLU/YEL”
wire open or shorted to
ground.Replace input shaft speed
sensor.
7B1-32 AUTOMATIC TRANSMISSION (4 A/T)
DTC P0720 (DTC NO.75) Output Speed Sensor Circuit Malfunction
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC, pending DTC and freeze frame data in PCM memory by using scan tool.
3) Start engine and shift transfer lever to “2H” or “4H” range.
4) Drive vehicle at 40 km/h (25 mile/h) or more for longer than 10 sec. (or higher than 3500 r/min engine speed
with “D” range for longer than 10 sec.)
5) Stop vehicle and check DTC and/or pending DTC.
1. PCM
2. Output shaft speed sensor
DTC DETECTING CONDITION TROUBLE AREA
•With 4WD LOW switch OFF, no output shaft speed
sensor signal is inputted while vehicle speed sensor
signal are inputted,
or
•With 4WD LOW switch OFF, no output shaft speed
sensor signal is inputted while engine running at
higher than specified engine speed with “D” range.
(2 driving cycle detection logic)•Output speed sensor or its circuit
•PCM
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester, on a level road.
AUTOMATIC TRANSMISSION (4 A/T) 7B1-35
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC, pending DTC and freeze frame data in PCM memory by using scan tool.
3) Start engine, warm it up to normal operating temperature and shift transfer lever to “2H” or “4H” range.
4) Shift selector lever in D range and keep it there for 10 seconds.
5) Increase vehicle speed to about 80 km/h (50 mile/h) in 4th gear and in D range.
6) Keep driving at above speed for 20 seconds.
7) Release accelerator pedal, decrease vehicle speed and stop vehicle.
8) Check DTC and/or pending DTC.
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester, on a level road.
Step Action Yes No
1Was “A/T DIAGNOSTIC FLOW TABLE” in this
section performed?Go to Step 2. Go to “A/T DIAGNOSTIC
FLOW TABLE” in this sec-
tion.
2 Check TCC solenoid circuit for short.
1) Turn ignition switch OFF and disconnect
PCM connectors.
2) Check for proper connection to PCM at ter-
minal C51-1-8.
3) If OK, then turn ignition switch ON and mea-
sure voltage between terminal C51-1-8 of
disconnected PCM connector and ground.
Is it about 0 V?Go to Step 3.“GRN/YEL” circuit shorted
to power circuit.
3 Check TCC solenoid circuit for open or short.
1) Turn ignition switch OFF.
2) Measure resistance between terminal C51-
1-8 of disconnected PCM connector and
ground.
Is it 11 – 15 Ω (at 20 °C (68 °F))?Intermittent trouble or
faulty PCM.
Check for intermittent
referring to “INTERMIT-
TENT AND POOR CON-
NECTION” in Section 0A.“GRN/YEL” circuit open or
shorted to ground.
If wire and connections
are OK, replace TCC
solenoid.