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.
Page 253 of 557

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-97
Fuse box Main
fuse
DOME
RADIO
“LAMP”
DTC P1510 ECM (PCM) BACK-UP POWER SUPPLY MALFUNCTION
CIRCUIT DESCRIPTION
Battery voltage is supplied so that diagnostic trouble code memory, values for engine control learned by ECM
(PCM), etc. are kept in ECM (PCM) even when the ignition switch is turned OFF.
DTC DETECTING CONDITION
POSSIBLE CAUSE
Low voltage at terminal C02-7 after starting engine.“W” circuit open
ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and run it at idle for 1 min.
2) Select “DTC” mode on scan tool and check DTC.
INSPECTION
STEPACTIONYESNO
1Check for voltage at terminal C02-7 of ECM
(PCM)connector connected, under each
condition, ignition switch OFF and engine
running.
Is it 10 – 14 V at each condition?Poor C02-7 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.“W” circuit open.
Page 254 of 557
6-1-98 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Ignition
switch
Main
fuseMain relay
Relay boxNo.1 injector
No.2 injector
No.3 injector
No.4 injector Fuse box
TABLE B-1 FUEL INJECTOR CIRCUIT CHECK
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check Injector for Operating Sound.
Using sound scope, check each injector for operating
sound at engine cranking.
Do all 4 injector make operating sound?Fuel injector circuit is
in good condition.Go to Step 3.
3Dose none of 4 injectors make operating sound at
Step 2?Go to Step 4.Check coupler
connection and wire
harness of injector
not making operatingnot making o erating
sound and injector
itself (Refer to Section
6E2).
4Check power circuit of injectors for open and short.
Is it normal?Check all 4 injectors
for resistance
respectively.
If resistance is OK,
substitute a known-
good ECM (PCM) and
recheck.Power circuit open or
short.
Page 255 of 557

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-99
Main
fuseIgnition
switch
Main relay
Fuel pump relay Main relay
Fuel pump
CAUTION: Check to make sure that connection is
made between correct terminals. Wrong connection
can cause damage to ECM (PCM), wire harness, etc.
TABLE B-2 FUEL PUMP AND ITS CIRCUIT CHECK
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE”.
2Check Fuel Pump Control System for Operation. See Fig. 1.
Is fuel pump heard to operate for 2 sec. after ignition switch
ON?Fuel pump circuit
is in good
condition.Go to Step 3.
3Check Fuel Pump for Operation.
1) Remove fuel pump relay from relay box with ignition
switch OFF.
2) Check for proper connection to relay at each terminals.
3) If OK, using service wire, connect terminals C44-3 and
C44-4 of relay connector. See Fig. 2.
Is fuel pump heard to operate at ignition switch ON?Go to Step 4.“P”, “B” or “R/B”
circuit open or fuel
pump malfunction.
4Check Fuel Pump Relay for Operation.
1) Check resistance between each two terminals of fuel
pump relay. See Fig.3.
Between terminals “c” and “d”: Infinity
Between terminals “a” and “b”: 100 – 150 Ω
2) Check that there is continuity between terminals “c” and
“d” when battery is connected to terminals “a” and “b”. See
Fig. 3.
Is fuel pump relay in good condition?“Y/Bl” circuit open
or poor C02-19
connection.
If wire and
connection are
OK, substitute a
known-good ECM
(PCM) and
recheck.Replace fuel pump
relay.
Page 256 of 557
6-1-100 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1 for Step 2 Fig. 2 for Step 3 Fig. 3 for Step 4