1999 SUZUKI GRAND VITARA 7b1

YH4
GRAND
VITARA
Oscilloscope waveforms
2 V/Div.
5 ms / Div.
Waveforms at about 25 mph, 40 km / h
AUTOMATIC TRANSMISSION (4 A / T) 7B1-45
TROUBLESHOOTING (DTC P0720)
STEPACTIONYESNO
1Was ªA / T DIAG. FLOW TABLEº performed?Go to Step 2.Go to ªA / T DIAG.
FLOW TABLEº.
2Output speed sensor circuit check:
1) Remove PCM cover.
2) With ignition switch OFF, disconnect PCM
connectors.
3) Check for proper connection to output speed sensor
at C51-1-22 and C51-1-23 terminals for G16 / J20
(at C51-1-9 and C51-1-10 terminals for H25).
4) If OK, check resistance of sensor circuit.
Resistance between C51-1-22
and C51-1-23 for G16 / J20
(C51-1-9 and C51-1-10 for H25): 387 ± 473
at
20 C, 68 F
Resistance between C51-1-22 /
C51-1-23 for G16/J20 (C51-1-9 /
C51-1-10 for H25) and ground: 1 M
or more
Are check results satisfactory?Go to Step 4.Go to Step 3.
3Output speed sensor check:
1) With ignition switch OFF, disconnect output speed
sensor connector.
2) Check for proper connection to output speed sensor
at each terminals.
3) If OK, then check resistance of output speed sensor.
Are measured values as specified in Step 2?ªOrº or ªWº wire
open or shorted to
ground.Replace output
speed sensor.
4Check visually output speed sensor and sensor rotor
for the followings.

No damage

No foreign material attached

Correct installation
Are they in good condition?Intermittent trouble
or faulty PCM.
Check for intermittent
referring to
ªIntermittent and
Poor Connectionº in
Section 0A.Clean, repair or
replace.
Reference
Connect oscilloscope between C51-1-23 (+) and C51-1-22 (±) for
G16/J20 (C51-1-10 (+) and C51-1-9 (±) for H25) of PCM connector
connected to PCM and check output speed sensor signal.

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.

YH4
GRAND
VITARA
7B1-48 AUTOMATIC TRANSMISSION (4 A / T)
TROUBLESHOOTING
STEPACTIONYESNO
1Was ªA / T DIAG. FLOW TABLEº performed?Go to Step 2.Go to ªA / T DIAG.
FLOW TABLEº.
2Is the vehicle equipped with monitor connector?Go to Step 3.Go to Step 4.
3Is DTC NO.65?G to Step 4.Go to Step 6.
4Check TCC Solenoid Circuit for Open or Short.
1) Turn ignition switch OFF and disconnect PCM
connectors.
2) Check for proper connection to PCM at terminals
C51-1-8 for G16 / J20 (C51-1-2 for H25).
3) If OK, then measure resistance between terminal
C51-1-8 for G16 / J20 (C51-1-2 for H25) of
disconnected PCM connector and ground.
Is it 11 ± 15
at 20
C, 68
F?Go to Step 5.ªG / Yº circuit open or
shorted to ground.
If wire and
connections are OK,
replace malfunction
shift solenoid.
5Check TCC Solenoid Circuit for Short.
1) Turn ignition switch ON.
2) Measure voltage between terminal C51-1-8 for
G16 / J20 (C51-1-2 for H25) of disconnected PCM
connector and ground.
Is it about 0 V?Intermittent trouble or
faulty PCM.
Check for
ªIntermittent and
Poor Connectionº in
Section 0A.ªG / Yº circuit shorted
to power circuit.
6Check TCC Solenoid Circuit for Short.
1) Turn ignition switch OFF and disconnect PCM
connectors.
2) Check for proper connection to PCM at terminals
C51-1-8 for G16 / J20 (C51-1-2 for H25) or C51-1-1.
3) If OK, then measure resistance between terminal
C51-1-8 for G16 / J20 (C51-1-2 for H25) of
disconnected PCM connector and ground.
Is it 11 ± 15
at 20
C, 68
F?Intermittent trouble or
faulty PCM.
Check for
ªIntermittent and
Poor Connectionº in
Section 0A.ªG / Yº circuit shorted
to ground.
If wire and
connections are OK,
replace malfunction
shift solenoid.

YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-49
DTC P0751 SHIFT SOLENOID VALVE-A (#1) PERFORMANCE OR STUCK OFF
DTC P0756 SHIFT SOLENOID VALVE-B (#2) PERFORMANCE OR STUCK OFF
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
While running in D range, gear change control from
PCM to A / T does not agree with actual A / T gear posi-
tion even though solenoid valve is electrically in good
condition.
(A / T gear position is calculated based on engine
speed signal and vehicle speed sensor signal.)
(2 driving cycles detection logic)DTC P0751:

Shift solenoid valve-A stuck or leakage.

2-3 shift valve stuck.

Valve body fluid passage clogged.

Mechanical malfunction in transmission.
(Direct clutch malfunction)
DTC P0756:

Shift solenoid valve-B stuck or leakage.

1-2 shift valve stuck.

3-4 shift valve stuck.

Valve body fluid passage clogged.

Mechanical malfunction in transmission.
(2nd brake malfunction)
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, 3rd and 4th in that
order as vehicle speed increases, referring to ªGear Shift Diagramº in this section.
5) Stop vehicle and 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.
2Shift solenoid valve-A or -B operation check:
1) Check shift solenoid valve-A or -B for operation
referring to ªSolenoid Valves Operation Checkº
section.
Is it in good condition?Go to Step 3.Faulty shift solenoid
valve-A or -B.
3Valve body check:
1) Check valve body and its passage referring to
ªUnit Repairº section.
Are they in good condition?Overhaul and repair
automatic transmis-
sion.Faulty valve body.

YH4
GRAND
VITARA
G16/J20 Engines H25 Engine
H25 Engine G16/J20 Engines
1. PCM
2. Shift solenoid-A
3. Shift solenoid-B
4. TCC solenoid
7B1-50 AUTOMATIC TRANSMISSION (4 A / T)
DTC P0753 (DTC NO.61 / 62) SHIFT SOLENOID-A (#1) ELECTRICAL
DTC P0758 (DTC NO.63 / 64) SHIFT SOLENOID-B (#2) ELECTRICAL
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
DTC P0753:
Voltage detected at C51-1-2 for G16/J20 (C51-1-6 for
H25) terminal is specified voltage or lower when shift
solenoid valve-A is ON or specified voltage or higher
when it is OFF.
Shift solenoid valve-A

Shift solenoid valve-A circuit

PCM
DTC P0758:
Voltage detected at C51-1-1 terminal is specified volt-
age or lower when shift solenoid valve-B is ON or spe-
cified voltage or higher when it is OFF.
Shift solenoid valve-B

Shift solenoid valve-B circuit

PCM

YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-51
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) Shift selector lever in D range and keep it for 10 seconds.
5) Drive vehicle about 30 km / h (20 mph) with 2nd gear in D range for 10 seconds.
6) Increase vehicle speed to about 80 km / h (50 mph) with 4th gear in D range and keep it for 10 seconds.
7) Release accelerator pedal, decrease vehicle speed and stop vehicle.
8) Check DTC and / or pending DTC.
TROUBLESHOOTING (DTC P0753 / P0758)
STEPACTIONYESNO
1Was ªA / T DIAG. FLOW TABLEº performed?Go to Step 2.Go to ªA / T DIAG.
FLOW TABLEº.
2Is the vehicle equipped with monitor connector?Go to Step 3.Go to Step 4.
3Is DTC NO.61 or 63?Go to Step 4.Go to Step 6.
4Check Shift Solenoid Circuit for Open or Short.
1) Turn ignition switch OFF and disconnect PCM
connectors.
2) Check for proper connection to PCM at terminals
C51-1-2 for G16 / J20 (C51-1-6 for H25) or C51-1-1.
3) If OK, then measure resistance between terminal
C51-1-2 for G16 / J20 (C51-1-6 for H25) or C51-1-1
of disconnected PCM connector and ground.
Is it 11 ± 15
at 20C, 68F?Go to Step 5.ªGº or ªG / Rº circuit
open or shorted to
ground.
If wire and
connections are OK,
replace malfunction
shift solenoid.
5Check Shift Solenoid Circuit for Short.
1) Turn ignition switch ON.
2) Measure voltage between terminal C51-1-2 for
G16 / J20 (C51-1-6 for H25) or C51-1-1 of
disconnected PCM connector and ground.
Is it about 0 V?Intermittent trouble or
faulty PCM.
Check for
ªIntermittent and
Poor Connectionº in
Section 0A.ªGº or ªG / Rº circuit
shorted to power
circuit.
6Check Shift Solenoid Circuit for Short.
1) Turn ignition switch OFF and disconnect PCM
connectors.
2) Check for proper connection to PCM at terminals
C51-1-2 for G16 / J20 (C51-1-6 for H25) or C51-1-1.
3) If OK, then measure resistance between terminal
C51-1-2 for G16/J20 (C51-1-6 for H25) or C51-1-1
of disconnected PCM connector and ground.
Is it 11 ± 15
at 20C, 68F?Intermittent trouble or
faulty PCM.
Check for
ªIntermittent and
Poor Connectionº in
Section 0A.ªGº or ªG / Rº circuit
shorted to ground.

YH4
GRAND
VITARA
G16 / J20 Engines
H25 Engine
1. PCM
2. 4WD low switch
3. J / C
7B1-52 AUTOMATIC TRANSMISSION (4 A / T)
DTC P1875 4WD LOW SWITCH CIRCUIT MALFUNCTION (if equipped)
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
While driving at higher than specified vehicle speed
and with more than specified throttle valve opening,
the following conditions are satisfied for specified time.

Vehicle speed sensed by vehicle speed sensor is
more than 10 km / h higher than that sensed by A / T
output speed sensor.
(2 driving cycles detection logic)
4WD LOW switch 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.
2) Clear DTC, pending DTC and freeze frame data in PCM memory by using scan tool.
3) Start engine.
4) Increase vehicle speed to about 30 km/h (19 mph) or more in D range and is in 2H position.
5) Keep driving at above vehicle speed for 30 seconds.
6) Stop vehicle and shift transfer lever to 4L position with A/T selector lever is in P range
7) Increase vehicle speed to about 25 km/h (15 mph) or more in D range and is in 4L position.
8) Keep driving at above vehicle speed for 30 seconds.
9) Stop vehicle and check pending DTC and DTC by using scan tool.