Page 245 of 557

Output shaft speed sensor (on A / T)
Counter
shaft
gear
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-89
DTC P0500 VEHICLE SPEED SENSOR (VSS) MALFUNCTION FOR A / T
VEHICLE
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
While fuel is kept cut at lower than 4000 r / min for
longer than 4 sec.
VSS signal not inputted.
2 driving cycle detection logic, continuous
monitoring.“P” or “Bl” circuit open or short.
Vehicle speed sensor malfunction.
Foreign material being attached or sensor installed
improperly.
Gear damaged.
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) Turn ignition switch OFF and then ON.
2) Clear DTC and warm up engine to normal operating temperature.
3) Increase vehicle speed to 50 mph, 80 km / h in “2” range.
4) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) for 4 sec.
or more.
5) Stop vehicle and check DTC and pending DTC.
Page 246 of 557

6-1-90 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1 for Step 2 Fig. 2 for Step 3
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE”.
2Check VSS for Resistance.
1) Disconnect VSS connection with ignition switch OFF.
2) Check for proper connection to VSS at “P” and “Bl” wire
terminals.
3) If OK, then check resistance of VSS. See Fig. 1.
Resistance between terminals : 100 – 300 Ω
Resistance between terminal
and transmission : 1 MΩ or more
Are check result satisfactory?Go to Step 3.Replace VSS.
3Check Visually VSS and Counter Shaft Gear for the
Following. See Fig. 2.
No damage
No foreign material attached
Correct installation
Are they in good condition?“P” or “Bl” wire
open or shorted to
ground or poor
C03-2 or C03-8
connection.
If wires and
connections are
OK, intermittent
trouble or faulty
ECM (PCM).
Check for
intermittent
referring to
“Intermittent and
Poor Connection”
in section 0A.Clean, repair or
replace.
Page 247 of 557
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-91
Relay box
Main fuseMain relay
IAC valveTo other valve
DTC P0505 IDLE CONTROL SYSTEM MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
No closed signal to IAC valve is detected after
engine start.
2 driving cycle detection logic, continuous monitoring.“R/B”, “V/W” or “B” circuit open or short
IAC valve malfunction
ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Start engine and run it at idle for 1 min.
4) Check DTC and pending DTC.
Page 248 of 557

6-1-92 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1 for Step 1 Fig. 2 for Step 2
When using SUZUKI scan tool: When not using SUZUKI scan tool:
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check Idle Air Control System.
When using SUZUKI scan too:
1) Connect SUZUKI scan tool to DLC with ignition
switch OFF, set parking brake and block drive
wheels.
2) Warm up engine to normal operating
temperature.
3) Clear DTC and select “MISC TEST” mode on
SUZUKI scan tool. See Fig. 1.
Is it possible to control (increase and reduce)
engine idle speed by using SUZUKI scan tool?
When not using SUZUKI scan tool:
1) Remove IAC valve from throttle boy referring to
“IAC Valve Removal” in Section 6E2.
2) Check IAC valve for operation referring to “IAC
Valve Inspection” in Section 6E2. See Fig. 2.
Is check result satisfactory?Intermittent trouble or
faulty ECM (PCM).
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0A.Go to Step 3.
3Check Wire Harness for Open and Short.
1) Turn ignition switch OFF.
2) Disconnect IAC valve connector.
3) Check for proper connection to IAC valve at
each terminals.
4) If OK, disconnect ECM (PCM) connector.
5) Check for proper connection to ECM (PCM) at
C01-6 terminal.
6) If OK, check “R/B”, “V/W” and “B” circuit for
open and short.
Are they in good condition?Replace IAC valve and
recheck.Repair or replace.
Page 249 of 557
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-93
DTC P0601 INTERNAL CONTROL MODULE MEMORY CHECK SUM ERROR
DTC DETECTING CONDITIONPOSSIBLE CAUSE
DTC P0601: Data write error (or check sum error)
when written into ECM (PCM)
1 driving cycle detection logic, continuous monitoring.ECM (PCM)
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON and then turn ignition switch OFF.
3) Start engine and run it at idle if possible.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
Substitute a known-good ECM (PCM) and recheck.
Page 250 of 557

6-1-94 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1 for Step 1
When using SUZUKI scan tool:
DTC P1450 BAROMETRIC PRESSURE SENSOR LOW / HIGH INPUT
DTC P1451 BAROMETRIC PRESSURE SENSOR PERFORMANCE PROBLEM
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Barometric pressure sensor is installed in ECM (PCM).
DTC DETECTING CONDITION
POSSIBLE CAUSE
DTC P1450:
Barometric pressure: 136 kPa 1025 mmHg or higher, or
33 kPa 250 mmHg or lowerECM (PCM) (barometric pressure sensor)
malfunction
DTC P1451:
Vehicle stopped
Engine cranking
Difference between barometric pressure and intake
manifold absolute pressure is 26 kPa, 200 mmHg or more
2 driving cycle detection logic, monitoring once / 1 driving.Manifold absolute pressure sensor and its
circuit malfunction
ECM (PCM) (barometric pressure sensor)
malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Turn ignition switch ON for 2 sec., crank engine for 2 sec. and run it at idle for 1 min.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
DTC P1450:
Substitute a known-good ECM (PCM) and recheck.
DTC P1451:
NOTE:
Note that atmospheric pressure varies depending on weather conditions as well as altitude.
Take that into consideration when performing these check.
STEP
ACTIONYESNO
11) Connect scan tool to DLC with ignition switch OFF.
2) Turn ignition switch ON and select “DATA
LIST” mode on scan tool.
3) Check manifold absolute pressure. See Fig. 1.
Is it barometric pressure (approx. 100 kPa,
760 mmHg) at sea level?Substitute a known-
good ECM (PCM) and
recheck.Go to Step 2.
Page 251 of 557
Applying Vacuum Displayed Value on Scan Tool
0Barometric pressure
(Approx. 100 kPa, 760 mmHg)
27 kPa
200 mmHgBarometric pressure –27 kPa
(Approx. 73 kPa, 560 mmHg
67 kPa
500 mmHgBarometric pressure –67 kPa
(Approx. 33 kPa, 260 mmHg)
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-95
Fig. 2 for Step 2
STEPACTIONYESNO
2Check MAP Sensor
1) Remove MAP sensor from intake manifold and connect
vacuum pump gauge to MAP sensor. See Fig. 2.
2) Connect scan tool to DLC and turn ignition switch ON.
3) Check intake manifold absolute pressure displayed on
scan tool under following conditions.
Is check result satisfactory?Check air intake
system for air
being drawn in
and engine
compression.
If OK, then
substitute a
known-good ECM
(PCM) and
recheck.Replace MAP
sensor.
Page 252 of 557

6-1-96 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Main
fuse
M/T vehicle
A/T vehicle
Ignition
switch
(starter
switch)
Starter
Starter Transmission
range sensor (switch) Main
fuse
Ignition
switch
(starter
switch)
DTC P1500 ENGINE STARTER SIGNAL CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
Low voltage at terminal C03-17 when cranking
engine or
High voltage at terminal C03-17 after starting engine.
2 driving cycle detection logic, continuous monitoring.“B/Y” circuit open
ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON, crank engine and run it at idle for 3 min.
3) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check for voltage at terminal C03-17 of ECM
(PCM) connector connected, under following
condition.
While engine cranking : 6 – 10 V
After starting engine : 0 V
Is voltage as specified?Poor C03-17
connection or
intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0A.
If wire and connections
are OK, substitute a
known-good ECM
(PCM) and recheck.“B/Y” circuit open.