1999 SUZUKI GRAND VITARA acc

YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-29
Gear shift Transmission fluid Running condition
ConditionPossible CauseCorrection
Poor 3±4 shift, ex-
3±4 shift valve stickingReplace.
cessive slippage
Shift solenoid valve-B stickingReplace.
Excessive shock on
Regulator valve stickingReplace.
1±2 shift
Faulty accumulator, second brake pistonReplace.
Excessive shock on
Regulator valve stickingReplace.
2±3 shift
Faulty accumulator, direct clutch pistonReplace.
Excessive shock on
3±4 shift
Regulator valve stickingReplace.
Non operate lock-
TCC (Lock-up) control valve stickingReplace.
up system
Solenoid valve No.2 (TCC solenoid valve)
stickingReplace.
TROUBLE DIAGNOSIS TABLE 3
ConditionPossible CauseCorrection
Low fluid pressure
Leakage from oil pressure circuitOverhaul.
Unable to run in all
range
Wear in oil pumpReplace.

Seizure in oil pumpReplace.

Fluid pressure leakage to over drive clutch
due to wear of oil pump bushingReplace.

Faulty in torque converterReplace.

YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-31
Brake pedal Released Depressed
Voltage 0 VBattery
voltage
DIAGNOSTIC FLOW TABLE A-1 (NO TCC LOCK-UP OCCURS)
SYSTEM DESCRIPTION
PCM turns TCC solenoid OFF under any of the following conditions.

Brake pedal switch: ON

4WD LOW switch: ON

Cruise control module: TCC OFF command signal is output (if equipped).

ECT: ECT < 30C (86F)
TROUBLESHOOTING
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and very careful during testing to avoid occurrence of an accident.

Road test should be carried out with 2 person, a driver and tester, on a level road.
STEPACTIONYESNO
1Was ªAUTOMATIC TRANSMISSION
DIAGNOSTIC FLOW TABLEº performed?Go to Step 2.Go to ªAUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLEº.
2ECT check:
(1) Warm up engine to normal operating
temperature.
(2) Check ECT using scan tool.
Is ECT more than 30C (86F)?Go to Step 3.Faulty ECT sensor, its
circuit or engine cooling
system.
If OK, substitute a known-
good PCM and recheck.
3Perform running test under the following
conditions and check voltage between
C51-1-8 (G16 / J20 engines) or C51-1-2 (H25
engine) terminal of PCM coupler and ground.

Normal mode in ªDº range.

Transfer ª2Hº position.

Cruise control is not operated (if equipped).

Brake pedal released.

Drive vehicle with TCC ON condition
referring to ªTCC lock-up diagramº in
this section.
Is it battery voltage?Faulty TCC solenoid
valve, its circuit or
transmission.Go to Step 4.
4Is vehicle equipped with H25 engine?Go to Step 5.Go to Step 6.
5Brake switch signal inspection:
(1) With ignition switch ON, check voltage
between E61-31 terminal of PCM coupler
terminal and ground.
Is the result as specified?Go to Step 6.Faulty brake pedal switch
or its circuit.
If OK, substitute a known-
good PCM and recheck.

YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-33
O / D cut
switchOFF ON
VoltageBattery
voltage0 V
DIAGNOSTIC FLOW TABLE A-2 (NO GEAR SHIFT TO O / D)
SYSTEM DESCRIPTION
PCM does not shift to O / D gear under any of the following conditions.

O / D cut switch: ON

4WD LOW switch: ON

Cruise control module: O / D OFF command signal is output (if equipped).

ECT: ECT < 30C (86F)
TROUBLESHOOTING
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and very careful during testing to avoid occurrence of an accident.

Road test should be carried out with 2 person, a driver and tester, on a level road.
STEPACTIONYESNO
1Was ªAUTOMATIC TRANSMISSION
DIAGNOSTIC FLOW TABLEº performed?Go to Step 2.Go to ªAUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLEº.
2ECT check:
(1) Warm up engine to normal operating
temperature.
(2) Check ECT using scan tool.
Is ECT more than 30C (86F)?Go to Step 3.Faulty ECT sensor,
its circuit or engine
cooling system.
If OK, substitute a known-
good PCM and recheck.
3Perform running test under the following
conditions and check voltage between
C51-1-2 (G16 / J20 engines) or C51-1-6 (H25
engine) terminal of PCM coupler and ground,
C51-1-1 terminal of PCM coupler and ground.

O / D cut switch OFF (ªO / D OFFº lamp OFF).

Normal mode in ªDº range.

Transfer ª2Hº position.

Cruise control is not operated (if equipped).

Drive vehicle with 4th gear condition
referring to ªGear shift diagramº in this
section.
Is each voltage about 0 V?Faulty shift solenoid
valve, its circuit or
transmission.ªGº wire or ªG / Rº wire
shorted to power circuit.
If OK, go to Step 4.
4O / D cut switch signal inspection:
(1) With ignition switch ON, check voltage
between E61-33 (G16 / J20 engines) or
E61-14 (H25 engine) terminal of PCM
coupler and ground.
Is the result as specified?Go to Step 5.Faulty O / D cut switch or
its circuit.
If OK, substitute a known-
good PCM and recheck.

YH4
GRAND
VITARA
7B1-40 AUTOMATIC TRANSMISSION (4 A / T)
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA

Transmission range switch signal (P, R, N, D, 2 or L)
is not inputted for 25 sec. at 60 km/h (38 mph) or
higher vehicle speed.
or

Multiple signals are inputted simultaneously for 25
sec.
(2 driving cycles detection logic)
Transmission range sensor (switch) maladjusted.

Transmission range sensor (switch) or its circuit mal-
function.

PCM
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
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.
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC 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 mph) 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.

YH4
GRAND
VITARA
G16/J20 Engines H25 Engine
G16/J20 Engines
H25 Engine
1. PCM
2. A / T input speed sensor 11 1 0
Bl / Y Bl / G16 8
Bl / Y Bl / G
7B1-42 AUTOMATIC TRANSMISSION (4 A / T)
DTC P0715 (DTC NO.76) INPUT / TURBINE SPEED SENSOR CIRCUIT MALFUNCTION
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
Input speed sensor detected speed is lower than spec-
ification while vehicle running under all of the following
conditions:

at higher than 10 km / h (7 mph) with 1st gear in D
range for 1 sec. or more.

at higher than 20 km / h (13 mph) with 2nd gear in D
range for 2 sec. or more.

at higher than 30 km / h (20 mph) with 3rd gear in D
range for 2 sec. or more.
(2 driving cycles detection logic)
Input speed sensor and its circuit

PCM
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
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.
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC.
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 mph) 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 mph) 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 mph) with 3rd gear in D range for 2 sec. or more.
8) Stop vehicle.
9) Check DTC and / or pending DTC.

YH4
GRAND
VITARA
G16/J20 Engines H25 Engine
G16/J20 Engines
H25 Engine
1. PCM
2. A / T output speed sensor 23
22
WOr10 9
WOr
7B1-44 AUTOMATIC TRANSMISSION (4 A / T)
DTC P0720 (DTC NO.75) OUTPUT SPEED SENSOR CIRCUIT MALFUNCTION
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA

With 4WD LOW switch OFF, no output speed sensor
signal is inputted while vehicle speed sensor signal
are inputted.
or

With 4WD LOW switch OFF, no output speed sensor
signal is inputted while engine running at higher than
specified engine speed with ªDº range.
(2 driving cycles detection logic)
A / T output speed sensor or its circuit

PCM
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
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.
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC.
3) Start engine and shift transfer lever to ª2Hº or ª4Hº range.
4) Drive vehicle at 40 km / h (25 mph) or more for longer than 10 sec. (or higher than 3500 rpm engine speed with
D range for longer than 10 sec.)
5) Stop vehicle and check DTC and / or pending DTC.

YH4
GRAND
VITARA
7B1-46 AUTOMATIC TRANSMISSION (4 A / T)
DTC P0741 TCC (LOCK-UP) SOLENOID VALVE PERFORMANCE OR STUCK OFF
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
While running in 2nd or 4th gear, D range, TCC control
of PCM does not agree with actual operation of trans-
mission TCC even though solenoid valve is electrically
in good condition.
(2 driving cycles detection logic)
TCC (lock-up) solenoid valve stuck

TCC control valve stuck

Valve body fluid passage clogged

TCC faulty
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
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.
1) Connect scan tool to DLC with ignition switch OFF.
2) Clear DTC, pending DTC and freeze frame data in PCM memory by using scan tool and check fuel level meter
indication is 1/4 or more.
3) Start engine, warm it up to normal operating temperature and shift transfer lever to ª2Hº or ª4Hº range.
4) Increase vehicle speed with D range, and check that gear position changes from 1st to 2nd and keep driving
about 20 mph, 30 km/h in 2nd of ªDº range for 10 seconds. (Throttle valve should be not at idle position and
the opening should be kept constant in this step.)
5) Keep driving about 50 mph, 80 km/h in 4th of ªDº range for 10 seconds.
6) Release accelerator pedal, decrease vehicle speed and stop vehicle.
7) Check pending DTC and DTC by using scan tool.
TROUBLESHOOTING
STEPACTIONYESNO
1Was ªA / T DIAG. FLOW TABLEº performed?Go to Step 2.Go to ªA / T DIAG.
FLOW TABLEº.
2TCC solenoid valve operation check:
1) Check TCC solenoid valve operation referring to
ªSolenoid Valves Operation Checkº in this section.
Is it in good condition?Go to Step 3.Faulty TCC solenoid
valve.
3Valve body check:
1) Check valve body referring to ªUnit Repairº in this
section.
Is it in good condition?Faulty torque
converter.Faulty valve body.

YH4
GRAND
VITARA
G16/J20 Engines H25 Engine
G16/J20 Engines
H25 Engine
1. PCM
2. Shift solenoid-A
3. Shift solenoid-B
4. TCC solenoid
AUTOMATIC TRANSMISSION (4 A / T) 7B1-47
DTC P0743 (DTC NO.65 / 66) TCC (LOCK-UP) SOLENOID ELECTRICAL
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
Voltage at terminal C51-1-8 for G16 / J20 (C51-1-2 for
H25) of PCM is high while TCC solenoid OFF is com-
manded or low while TCC solenoid ON is comman-
ded.
TCC (lock-up) solenoid valve

TCC (lock-up) solenoid valve circuit

PCM
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
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.
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC.
3) Start engine, warm it up to normal operating temperature and shift transfer lever to ª2Hº or ª4Hº 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 mph) 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.