Page 158 of 557

6-1-2 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
DTC P0300 Random Misfire
Detected 6-1- 69. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0301 Cylinder 1 Misfire
Detected 6-1- 69. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0302 Cylinder 2 Misfire
Detected 6-1- 69. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0303 Cylinder 3 Misfire
Detected 6-1- 69. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0304 Cylinder 4 Misfire
Detected 6-1- 69. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0335 CKP Sensor Circuit
Malfunction 6-1- 73. . . . . . . . . . . . . . . . . . . . . . . .
DTC P0340 CMP Sensor Circuit
Malfunction 6-1- 75. . . . . . . . . . . . . . . . . . . . . . . .
DTC P0400 EGR Flow Malfunction 6-1- 78. . . .
DTC P0420 Catalyst System
Efficiency Below Threshold 6-1- 81. . . . . . . . . .
DTC P0443 Purge Control Valve Circuit
Malfunction 6-1- 84. . . . . . . . . . . . . . . . . . . . . . . .
DTC P0480 Radiator Fan Control
System Malfunction 6-1- 85. . . . . . . . . . . . . . . . .
DTC P0500 Vehicle Speed Sensor
Malfunction 6-1- 87. . . . . . . . . . . . . . . . . . . . . . . .
DTC P0505 Idle Control System
Malfunction 6-1- 91. . . . . . . . . . . . . . . . . . . . . . . . DTC P0601 Internal Control Module
Memory Check Sum Error 6-1- 93. . . . . . . . . . .
DTC P1450 Barometric Pressure
Sensor Low / High Input 6-1- 94. . . . . . . . . . . . .
DTC P1451 Barometric Pressure Sensor
Performance Problem 6-1- 94. . . . . . . . . . . . . . .
DTC P1500 Engine Starter Signal
Circuit Malfunction 6-1- 96. . . . . . . . . . . . . . . . . .
DTC P1510 ECM (PCM) Back-up
Power Supply Malfunction 6-1- 97. . . . . . . . . . .
Table B-1 Fuel Injector Circuit Check 6-1- 98. . .
Table B-2 Fuel Pump and Its Circuit
Check 6-1- 99. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table B-3 Fuel Pressure Check 6-1-101. . . . . . . .
Table B-4 A / C Signal Circuits Check 6-1-103. . .
Table B-5 PSP Switch Signal Circuit
Check 6-1-104. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table B-6 Electric Load Signal Circuit
Check 6-1-105. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table B-7 Radiator Cooling Fan Control
System Check 6-1-106. . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS6-1-108 . . . . . . . . . . . . . . . . . . . . .
Page 165 of 557

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-9
PRECAUTION IN DIAGNOSING TROUBLE
Don’t disconnect couplers from ECM (PCM), battery cable from
battery, ECM (PCM) ground wire harness from engine or main
fuse before confirming diagnostic information (DTC, freeze frame
data, etc.) stored in ECM (PCM) memory. Such disconnection will
erase memorized information in ECM (PCM) memory.
Diagnostic information stored in ECM (PCM) memory can be
cleared as well as checked by using SUZUKI scan tool (Tech-1)
or generic scan tool. Before using scan tool, read its Operator’s
(Instruction) Manual carefully to have good understanding as to
what functions are available and how to use it.
Priorities for diagnosing troubles
If two or more DTCs are stored, proceed to the flow table of the
DTC which was detected earliest in the order and follow the
instruction in that table.
If no instructions are given, troubleshoot DTCs according to the
following priorities.
1. Diagnostic trouble codes (DTCs) other than DTC
P0171 / P0172 (Fuel system too lean / too rich), DTC
P0300 / P0301 / P0302 / P0303 / P0304 (Misfire detected) and
DTC P0400 (EGR flow malfunction)
2. DTC P0171 / P0172 (Fuel system too lean / too rich) and DTC
P0400 (EGR flow malfunction)
3. DTC P0300 / P0301 / P0302 / P0303 / P0304 (Misfire detected)
Be sure to read “Precautions for Electrical Circuit Service” in Sec-
tion 0A before inspection and observe what is written there.
ECM (PCM) Replacement
When substituting a known-good ECM (PCM), check for following
conditions. Neglecting this check may cause damage to a known-
good ECM (PCM).
–Resistance value of all relays, actuators is as specified respec-
tively.
–MAP sensor and TP sensor are in good condition and none of
power circuits of these sensors is shorted to ground.
Page 189 of 557
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-33
1. ECM (PCM)
2. ECM (PCM) couplers
(Viewed from harness side)
INSPECTION OF ECM (PCM) AND ITS
CIRCUITS
ECM (PCM) and its circuits can be checked at ECM (PCM) wiring
couplers by measuring voltage and resistance.
CAUTION:
ECM (PCM) cannot be checked by itself. It is strictly prohib-
ited to connect voltmeter or ohmmeter to ECM (PCM) with
coupler disconnected from it.
Voltage Check
1) Remove ECM (PCM) (1) from body referring to Section 6E2.
2) Check voltage at each terminal of couplers (2) connected.
NOTE:
As each terminal voltage is affected by the battery voltage,
confirm that it is 11 V or more when ignition switch is ON.
Page 193 of 557

1 2
1. ECM (PCM) coupler disconnected
2. Ohmmeter
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-37
Resistance Check
1) Disconnect ECM (PCM) couplers from ECM (PCM) with ignition
switch OFF.
CAUTION:
Never touch terminals of ECM (PCM) itself or connect
voltmeter or ohmmeter.
2) Check resistance between each terminal of couplers discon-
nected.
CAUTION:
Be sure to connect ohmmeter probe from wire harness
side of coupler.
Be sure to turn OFF ignition switch for this check.
Resistance in table below represents that when parts
temperature is 20C (68F).
TERMINALSCIRCUITSTANDARD RESISTANCE
C01-7 to C03-6HO2S-1 heater11.7 – 15.6 Ω
C02-4 to C03-6HO2S-2 heater11.7 – 15.6 Ω
C01-9 to C02-5 / 6No.1 injector12.0 – 13.0 Ω
C01-21 to C02-5 / 6No.2 injector12.0 – 13.0 Ω
C01-31 to C02-5 / 6No.3 injector12.0 – 13.0 Ω
C01-8 to C02-5 / 6No.4 injector12.0 – 13.0 Ω
C02-2 to C02-5 / 6EGR valve (stepper motor coil 4)20 – 24 Ω
C02-9 to C02-5 / 6EGR valve (stepper motor coil 3)20 – 24 Ω
C02-8 to C02-5 / 6EGR valve (stepper motor coil 2)20 – 24 Ω
C02-17 to C02-5 / 6EGR valve (stepper motor coil 1)20 – 24 Ω
C01-4 to C02-5 / 6EVAP canister purge valve30 – 34 Ω
C02-19 to C03-6Fuel pump relay70 – 110 Ω
C02-1 to Body groundA / C control moduleNo continuity
C02-18 to C02-5 / 6Radiator fan control relay70 – 110 Ω
C02-10 to C02-7Main relay70 – 110 Ω
C01-1 to Body groundGroundContinuity
C01-2 to Body groundGroundContinuity
C01-3 to Body groundGroundContinuity
Page 197 of 557

Main
fuseIgnition
switch
Main
relay Malfunction indicator lamp in combination meter
Relay
box
Fuse box
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-41
TABLE A-3 ECM (PCM) POWER AND GROUND CIRCUIT CHECK – MIL
DOESN’T LIGHT AT IGNITION SWITCH ON AND ENGINE DOESN’T
START THOUGH IT IS CRANKED UP
CIRCUIT DESCRIPTION
When the ignition switch tuned ON, the main relay turns ON (the contact point closes) and the main power is sup-
plied to ECM (PCM).
INSPECTION
STEPACTIONYESNO
1Main Relay Operating Sound Check
Is operating sound of main relay heard at ignition switch ON?Go to Step 5.Go to Step 2.
2Main Relay Check
1) Turn OFF ignition switch and remove main relay (1).
2) Check for proper connection to main relay (1) at terminal
3 and 4.
3) Check resistance between each two terminals. See Fig. 1
and 2.
Between terminals 1 and 2: Infinity
Between terminals 3 and 4: 100 – 150 Ω
4) Check that there is continuity between terminals 1 and 2
when battery is connected to terminals 3 and 4. See Fig. 3.
Is main relay in good condition?Go to Step 3.Replace main
relay.
3Fuse Check
Is main “FI” fuse in good condition?Go to Step 4.Check for short in
circuits connected
to this fuse.
4ECM (PCM) Power Circuit Check
1) Turn OFF ignition switch, disconnect connectors from ECM
(PCM) and install main relay.
2) Check for proper connection to ECM (PCM) at terminals
C03-6, C02-10, C02-5 and C02-6.
3) If OK, then measure voltage between terminal C03-6 and
ground, C02-10 and ground with ignition switch ON.
Is each voltage 10 – 14 V?Go to Step 5.“B/W”, “W/R” or
“Gr” circuit open.
Page 198 of 557
6-1-42 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1 for Step 2 Fig. 2 for Step 2 Fig. 3 for Step 2
STEPACTIONYESNO
5ECM (PCM) Power Circuit Check
1) Using service wire, ground terminal C02-10 and
measure voltage between terminal C02-5 / 6 and
ground at ignition switch ON.
Is it 10 – 14 V?Check ground circuits
“B/Y” and “B” for
open.
If OK, then substitute a
known-good ECM
(PCM) and recheck.Go to Step 6.
6Is operating sound of main relay heard in Step 1?Go to Step 7.“W/R” or “R/B” wire
open.
7Main Relay Check
1) Check main relay according to procedure in
Step 2.
Is main relay in good condition?“W/R” or “R/B” wire
open.Replace main relay.
Page 259 of 557

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-103
A/C
amplifier(A / C ON output signal)
(A / C input signal)
TABLE B-4 A / C SIGNAL CIRCUITS CHECK (VEHICLE WITH A / C)
INSPECTION
STEPACTIONYESNO
1Check A / C (input) Signal Circuit.
1) Check voltage at terminal C02-16. See Fig. 1.
While engine running and A / C
switch and / or heater blower switch
OFF (A / C is not operating) : 10 – 14 V
While engine running and both
A / C switch and heater blower
switch ON (A / C is operating) : About 0 V
Are check result as specified?Go to Step 2.“Lg / B” circuit open
or short,
Evaporative
temperature is
1C (34F) below
or faulty A / C
system.
2Check A / C ON (Output) Signal Circuit.
1) Check voltage at terminal C02-1. See Fig. 2.
While engine running and A / C
switch and / or heater blower
switch OFF (A / C is not operating) : About 0 V
While engine running at idle speed
and both A / C switch and heater blower
switch ON (A / C is operating) : 10 – 14 V
Are check result as specified?A / C control signal
circuits are in good
condition.“G/R” circuit open
or short, Poor
performance of
ECT sensor, TP
sensor, Engine
start signal
inputted or A / C
amplifier
malfunction.
If none of the
above exists,
substitute a
known-good ECM
and recheck.
Page 471 of 557

6F-4 IGNITION SYSTEM
STEPACTIONYESNO
6Ignition Coil Power Supply and Ground Circuit
Check
1) Check ignition coil power supply (“B/W” wire)
circuit for open and short.
Are circuits in good condition?Go to Step 7.Repair or replace.
7Ignition Coil Check
1) Check ignition coil for resistance, referring to
“Ignition Coil” in this section.
Is check result satisfactory?Go to Step 8.Replace ignition coil
assembly.
8CMP Sensor Check
1) Check CMP sensor and signal rotor, referring to
“Distributor Unit” in this section.
Is check result satisfactory?Go to Step 9 on the
next page.Adjust or replace.
9Ignition Trigger Signal Circuit Check
1) Check ignition trigger signal (“Br / Y” or “Or” wire)
circuit for open, short and poor connection.
Are circuits in good condition?Go to Step 10.Repair or replace.
10Igniter Check
1) Check igniter, referring to “Igniter” in this section.
Is check result satisfactory?Go to Step 11.Replace igniter.
11Ignition Timing Check
1) Check initial ignition timing and ignition timing
advance, referring to “Ignition Timing” in this
section.
Is check result satisfactory?Substitute a known-
good ECM (or PCM)
and then repeat
Step 2.Go to Step 12.
12Ignition Timing Adjustment and Recheck
1) Adjust initial ignition timing, referring to “Ignition
Timing” in this section.
2) Recheck initial ignition timing and ignition timing
advance, referring to “Ignition Timing” in this
section.
Is check result satisfactory?System is in good
condition.Substitute a known-
good ECM (or PCM)
and then repeat
Step 2.