Diagnostic Flow Table A-2 - Suzuki sq-416-420-625 Service Manual

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.
D O/D cut switch: ON
D 4WD LOW switch: ON
D Cruise control module: O/D OFF command signal is output (if equipped).
D ECT: ECT < 30_C (86_F)
TROUBLESHOOTING
WARNING:
D 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.
D Road test should be carried out with 2 person, a driver and tester, on a level road.
STEP
1 Was "AUTOMATIC TRANSMISSION
DIAGNOSTIC FLOW TABLE" performed?
2 ECT check:
(1) Warm up engine to normal operating
temperature.
(2) Check ECT using scan tool.
Is ECT more than 30_C (86_F)?
3 Perform 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.
D O/D cut switch OFF ("O/D OFF" lamp OFF).
D Normal mode in "D" range.
D Transfer "2H" position.
D Cruise control is not operated (if equipped).
D Drive vehicle with 4th gear condition
referring to "Gear shift diagram" in this
section.
Is each voltage about 0 V?
4 O/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.
O/D cut
switch
Voltage
Is the result as specified?
ACTION
OFF ON
Battery
0 V
voltage
AUTOMATIC TRANSMISSION (4 A / T) 7B1-33
YES
Go to Step 2.
Go to Step 3.
Faulty shift solenoid
valve, its circuit or
transmission.
Go to Step 5.
NO
Go to "AUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLE".
Faulty ECT sensor,
its circuit or engine
cooling system.
If OK, substitute a known-
good PCM and recheck.
"G" wire or "G/R" wire
shorted to power circuit.
If OK, go to Step 4.
Faulty O/D cut switch or
its circuit.
If OK, substitute a known-
good PCM and recheck.