1999 SUZUKI GRAND VITARA tran

7B1-18 AUTOMATIC TRANSMISSION (4 A/T)
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 < 30 °C (86 °F)
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent 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.
Step Action Yes No
1Was “AUTOMATIC TRANSMISSION DIAG-
NOSTIC FLOW TABLE” performed?Go to Step 2. Go to “AUTOMATIC
TRANSMISSION DIAG-
NOSTIC FLOW TABLE” in
this section.
2 ECT check :
1) Warm up engine to normal operating tem-
perature.
2) Check ECT using scan tool.
Is ECT more than 30 °C (86 °F)?Go to Step 3. Faulty ECT sensor, its cir-
cuit or engine cooling sys-
tem.
If OK, substitute a known-
good PCM and recheck.
3 Perform running test under the following condi-
tions and check voltage between C51-1-8 termi-
nal of PCM coupler and ground.
•Normal mode in “D” range.
•Transfer “2H” position.
•Cruise control is not operated (if equipped).
•Brake pedal released.
•Drive vehicle with TCC ON condition refer-
ring to “TCC LOCK-UP DIAGRAM” in this
section.
Is it battery voltage?Faulty TCC solenoid
valve, its circuit or trans-
mission.Go to Step 4.
4 Brake switch signal inspection :
With ignition switch ON, check voltage between
E61-34 terminal of PCM coupler terminal and
ground.
Brake switch specification
Brake pedal released : 0 V
Brake pedal depressed : Battery voltage
Is the result as specified?Go to Step 5. Faulty brake pedal switch
or its circuit.
If OK, substitute a known-
good PCM and recheck.

AUTOMATIC TRANSMISSION (4 A/T) 7B1-19
5“4WD LOW” switch signal inspection :
With ignition switch ON, check voltage between
C51-1-26 terminal of PCM coupler and ground.
“4WD LOW” switch specification
Transfer gear position “4L” or “N” : 0 V
Transfer gear position “4H” or “2H” :
Battery voltage
Is the result as specified?Go to Step 6. Faulty “4WD LOW” switch
or its circuit.
If OK, substitute a known-
good PCM and recheck.
6 Is vehicle equipped with cruise control system? Go to Step 7. Substitute a know-good
PCM and recheck.
7 Cruise control signal inspection :
With ignition switch ON, check voltage between
E61-35 terminal of PCM coupler and ground.
Is it battery voltage?Substitute a known-good
PCM and recheck.Faulty cruise control mod-
ule or its circuit.
If OK, substitute a known-
good PCM and recheck. Step Action Yes No

7B1-20 AUTOMATIC TRANSMISSION (4 A/T)
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 off switch : ON
•4WD LOW switch : ON
•Cruise control module : O/D OFF command signal is output (if equipped).
•ECT : ECT < 30 °C (86 °F)
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent 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.
Step Action Yes No
1Was “AUTOMATIC TRANSMISSION DIAG-
NOSTIC FLOW TABLE” performed?Go to Step 2. Go to “AUTOMATIC
TRANSMISSION DIAG-
NOSTIC FLOW TABLE” in
this section.
2 ECT check :
1) Warm up engine to normal operating tem-
perature.
2) Check ECT using scan tool.
Is ECT more than 30 °C (86 °F)?Go to Step 3. Faulty ECT sensor, its cir-
cuit or engine cooling sys-
tem.
If OK, substitute a known-
good PCM and recheck.
3 Perform running test under the following condi-
tions and check voltage between C51-1-2 termi-
nal of PCM coupler and ground, C51-1-1
terminal of PCM coupler and ground.
•O/D off switch OFF (“O/D OFF” lamp OFF).
•Normal mode in “D” range.
•Transfer “2H” position.
•Cruise control is not operated (if equipped).
•Drive vehicle with 4th gear condition refer-
ring to “Gear shift diagram” in this section.
Is each voltage about 0 V?Faulty shift solenoid valve,
its circuit or transmission“GRN” wire or “GRN/
RED” wire shorted to
power circuit.
If OK, go to Step 4.
4 O/D off switch signal inspection :
With ignition switch ON, check voltage between
E61-33 terminal of PCM coupler and ground.
“O/D” cut switch specification
“O/D” cut switch OFF : Battery voltage
“O/D” cut switch ON : 0 V
Is the result as specified?Go to Step 5. Faulty O/D off switch or its
circuit.
If OK, substitute a known-
good PCM and recheck.

AUTOMATIC TRANSMISSION (4 A/T) 7B1-21
5“4WD LOW” switch signal inspection :
With ignition switch ON, check voltage between
C51-1-26 terminal of PCM coupler and ground.
“4WD LOW” switch specification
Transfer gear position “4L” or “N” : 0 V
Transfer gear position “4H” or “2H” :
Battery voltage
Is the result as specified?Go to Step 6. Faulty “4WD LOW” switch
or its circuit.
If OK, substitute a known-
good PCM and recheck.
6 Is vehicle equipped with cruise control system? Go to Step 7. Substitute a known-good
PCM and recheck.
7 Cruise control signal inspection :
With ignition switch ON, check voltage between
E61-35 terminal of PCM coupler and ground.
Is it battery voltage?Substitute a known-good
PCM and recheck.Faulty cruise control mod-
ule or its circuit.
If OK, substitute a known-
good PCM and recheck. Step Action Yes No

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.

AUTOMATIC TRANSMISSION (4 A/T) 7B1-23
Table B-2 : “O/D OFF” Light Circuit Check (“O/D OFF” Light Comes ON
Steadily)
WIRING DIAGRAM
Refer to “TABLE B-1” in this section.
TROUBLESHOOTING
[A] for Step 1/[B] for Step 4Step Action Yes No
1 Check O/D off switch status.
Press O/D off switch button (1).
Does “O/D OFF” lamp come ON steadily?Go to Step 2. System is OK.
2 Check lamp circuit for short.
1) Turn ignition switch OFF and disconnect
PCM connectors.
2) Turn ignition switch ON.
Does “O/D OFF” lamp come ON steadily?“WHT/BLK” circuit
shorted to ground.Go to Step 3.
3 Check O/D off switch circuit.
1) Check resistance between terminal E61-33
of disconnected PCM connector and body
ground with O/D off switch button (1)
released.
Is continuity indicated?Go to Step 4. Check PCM ground circuit
for open.
If ground circuit is OK,
substitute a known-good
PCM and recheck.
4 Check O/D off switch for operation.
1) Remove console box.
2) Disconnect O/D off switch connector.
3) Check continuity between switch terminals
under each condition below.
O/D switch operation
With O/D off switch button (1) released :
No continuity
With O/D off switch button (1) pressed :
Continuity
Is check result satisfactory?“YEL/RED” circuit shorted
to ground.Replace O/D off switch.

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) 7B1-25
Table B-4 : “POWER” Light Circuit Check (“POWER” Light Comes ON
Steadily)
WIRING DIAGRAM
Refer to “TABLE B-3” in this section.
TROUBLESHOOTING
[A] for Step 1/[B] for Step 4Step Action Yes No
1 Check Power/Normal change switch position.
Is switch button at Normal position?Go to Step 2. Set Power/Normal
change switch at Nor-
mal position.
2 Check lamp circuit for short.
1) Turn ignition switch OFF and disconnect PCM
connectors.
2) Turn ignition switch ON.
Does “POWER” lamp come ON steadily?“GRY/BLU” circuit
shorted to ground.Go to Step 3.
3 Check Power/Normal change switch circuit.
1) Check resistance between terminal E61-31 of dis-
connected PCM connector and body ground with
P/N change switch OFF.
Is continuity indicated?Go to Step 4. Check PCM ground
circuit for open.
If ground circuit is OK,
substitute a known-
good PCM and
recheck.
4 Check Power/Normal change switch for operation.
1) Remove Power/Normal change switch.
2) Check continuity between switch terminals “4” and
“5” under each condition below.
Normal position: No continuity
Power position: Continuity.
Is check result satisfactory?“ORN/BLU” circuit
shorted to ground.Replace Power/Normal
change switch.