
6-1-2 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Table A-4 Malfunction Indicator Lamp
Check – MIL Does Not Flash or Just
Remains ON Even with Grounding
Diagnosis Switch Terminal (Vehicle with
Monitor Connector) ................................... 6-1-45
Table A-5 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 .................. 6-1-46
DTC P0100 (DTC No.33, 34) Mass Air
Flow Circuit Malfunction ............................ 6-1-48
DTC P0110 (DTC No.23, 25) Intake Air
Temp. (IAT) Circuit Malfunction ................ 6-1-50
DTC P0115 (DTC No.14, 15) Engine
Coolant Temp. Circuit Malfunction ............ 6-1-52
DTC P0120 (DTC No.21, 22) Throttle
Position Circuit Malfunction....................... 6-1-54
DTC P0121 Throttle Position Circuit
Range/Performance Problem ................... 6-1-56
DTC P0130 (DTC No.13) HO2S-1 (Bank 1)
Circuit Malfunction or No Activity
Detected.................................................... 6-1-58
DTC P0133 HO2S-1 (Bank 1) Circuit Slow
Response .................................................. 6-1-60
DTC P0135 HO2S-1 (Bank 1) Heater
Circuit Malfunction .................................... 6-1-61
DTC P0136 HO2S-2 (Bank 1) Circuit
Malfunction................................................ 6-1-63
DTC P0141 HO2S-2 (Bank 1) Heater
Circuit Malfunction .................................... 6-1-65
DTC P0150 (DTC No.26) HO2S-1 (Bank 2)
Circuit Malfunction or No Activity
Detected.................................................... 6-1-67
DTC P0153 HO2S-1 (Bank 2) Circuit Slow
Response .................................................. 6-1-69
DTC P0155 HO2S-1 (Bank 2) Heater
Circuit Malfunction .................................... 6-1-70
DTC P0156 HO2S-2 (Bank 2) Circuit
Malfunction................................................ 6-1-72
DTC P0161 HO2S-2 (Bank 2) Heater
Circuit Malfunction .................................... 6-1-74
DTC P0171/P0172 Fuel System Too
Lean/Rich (Bank 1) ................................... 6-1-76
DTC P0174/P0175 Fuel System Too
Lean/Rich (Bank 2) ................................... 6-1-78
DTC P0300/P0301/P0302/P0303/P0304/
P0305/P0306 Random Misfire/Cylinder 1
Misfire/Cylinder 2 Misfire/Cylinder 3 Misfire/
Cylinder 4 Misfire Detected/Cylinder 5
Misfire Detected/Cylinder 6 Misfire
Detected.................................................... 6-1-80
DTC P0325 (DTC No.43) Knock Sensor Circuit Malfunction ..................................... 6-1-82
DTC P0335 Crankshaft Position Sensor
Circuit Malfunction ..................................... 6-1-84
DTC P0340 (DTC No.42) Camshaft
Position Sensor Circuit Malfunction ........... 6-1-86
DTC P0400 Exhaust Gas Recirculation
Flow Malfunction ........................................ 6-1-89
DTC P0403 (DTC No.51) Exhaust Gas
Recirculation Circuit Malfunction ............... 6-1-92
DTC P0420 Catalyst System Efficiency
Below Threshold (Bank 1) ......................... 6-1-94
DTC P0430 Catalyst System Efficiency
Below Threshold (Bank 2) ......................... 6-1-96
DTC P0443 Evap Control System Purge
Control Valve Circuit Malfunction............... 6-1-98
Evap canister purge system
inspection ............................................. 6-1-100
Vacuum passage inspection ................ 6-1-100
Vacuum hose inspection ...................... 6-1-101
Evap canister purge valve and its
circuit inspection .................................. 6-1-101
Evap canister purge valve inspection .. 6-1-101
DTC P0460 Fuel Level Sensor Circuit
High Input ................................................ 6-1-103
DTC P0500 (DTC No.24) Vehicle Speed
Sensor Malfunction .................................. 6-1-105
DTC P0505 Idle Air Control System
Malfunction .............................................. 6-1-108
DTC P0601 (DTC No.71) Internal Control
Module Memory Check Sum Error .......... 6-1-110
DTC P1408 Manifold Absolute Pressure
Sensor Circuit Malfunction ....................... 6-1-111
DTC P1450/P1451 Barometric Pressure
Sensor Circuit Malfunction/Performance
Problem ................................................... 6-1-113
DTC P1500 Engine Starter Signal Circuit
Malfunction .............................................. 6-1-114
DTC P1510 Ecm Back-Up Power Supply
Malfunction .............................................. 6-1-115
Table B-1 Fuel Pump Circuit Inspection .. 6-1-116
Table B-2 Fuel Injectors and Circuit
Inspection ................................................ 6-1-117
Table B-3 Fuel Pressure Inspection ........ 6-1-119
Table B-4 Idle Air Control System
Inspection ................................................ 6-1-121
Table B-5 A/C Signal Circuits Inspection
(If Equipped) ............................................ 6-1-123
Table B-6 A/C Condenser Fan Motor
Relay Control System Inspection
(If Equipped) ............................................ 6-1-124
Special Tool ............................................... 6-1-125

6-1-8 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Priority of Freeze Frame Data
ECM (PCM) has 4 frames where the freeze frame data can be stored. The first frame stores the freeze frame
data of the malfunction which was detected first. However, the freeze frame data stored in this frame is updated
according to the priority described below. (If malfunction as described in the upper square “1” below is detected
while the freeze frame data in the lower square “2” has been stored, the freeze frame data “2” will be updated by
the freeze frame data “1”.)
In the 2nd through the 4th frames, the freeze frame data of each malfunction is stored in the order as the mal-
function is detected. These data are not updated regardless of the priority.
Shown in the table below are examples of how freeze frame data are stored when two or more malfunctions are
detected.
Freeze Frame Data Clearance
The freeze frame data is cleared at the same time as clearance of DTC.
DATA LINK CONNECTOR (DLC)
DLC (1) is in compliance with SAEJ1962 in its installation posi-
tion, the shape of connector and pin assignment.
K line of ISO 9141 is used for SUZUKI scan tool or generic scan
tool to communicate with ECM (PCM), ABS control module and
Air bag SDM. SUZUKI serial data line is used for SUZUKI scan
tool to communicate with Immobilizer control module. PRIORITY FREEZE FRAME DATA IN FRAME 1
1Freeze frame data at initial detection of malfunction among misfire detected (P0300-P0306), fuel
system too lean (P0171, P0174) and fuel system too rich (P0172, P0175)
2 Freeze frame data when a malfunction other than those in “1” above is detected
FRAME 1 FRAME 2 FRAME 3 FRAME 4
FREEZE FRAME
DATA to be updated1st FREEZE
FRAME DATA2nd FREEZE
FRAME DATA3rd FREEZE
FRAME DATA
No malfunction No freeze frame dataNo freeze frame
dataNo freeze frame
dataNo freeze frame
data
MALFUNCTION
DETECTED ORDER
1P0110 (IAT)
detectedData at P0110
detectionData at P0110
detectionNo freeze frame
dataNo freeze frame
data
2P0171 (Fuel sys-
tem) detectedData at P0171
detectionData at P0110
detectionData at P0171
detectionNo freeze frame
data
3P0300 (Misfire)
detectedData at P0171
detectionData at P0110
detectionData at P0171
detectionData at P0300
detection
4P0301 (Misfire)
detectedData at P0171
detectionData at P0110
detectionData at P0171
detectionData at P0300
detection
2. B+
3. SUZUKI Serial data line
4. K line of ISO 9141
5. Body ground
6. ECM ground

6-1-10 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DATA LINK CONNECTOR (DLC)
DLC (1) is in compliance with SAEJ1962 in its installation posi-
tion, the shape of connector and pin assignment.
K line of ISO 9141 is used for SUZUKI scan tool to communicate
with ECM (PCM), ABS control module and air bag SDM. SUZUKI
serial data line is used for SUZUKI scan tool to communicate with
Immobilizer control module.
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 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 (Vehicle without monitor connector)
If two or more diagnostic trouble codes (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 diagnostic trouble codes according to the following priorities.
– Diagnostic trouble codes (DTCs) other than DTC P0171/P0172/P0174/P0175 (Fuel system too lean/too
rich), DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire detected) and DTC P0400 (EGR
flow malfunction)
– DTC P0171/P0172/P0174/P0175 (Fuel system too lean/too rich) and DTC P0400 (EGR flow malfunction)
– DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire detected)
• Be sure to read “PRECAUTIONS FOR ELECTRICAL CIRCUIT SERVICE” in Section 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 respectively.
– MAF sensor, MAP sensor and TP sensor are in good condition and none of power circuits of these sen-
sors is shorted to ground.
2. B+
3. SUZUKI Serial data line
4. K line of ISO 9141
5. Body ground
6. ECM ground

6-1-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
P0174 Fuel system too lean (Bank 2)Short term fuel trim or total fuel trim
(short and long terms added) is larger
than specification for specified time or
longer. (Fuel trim toward rich side is
large.)2 driving
cyclesNot
applicable
P0175 Fuel system too rich (Bank 2)Short term fuel trim or total fuel trim
(short and long terms added) is
smaller than specification for specified
time or longer. (Fuel trim toward lean
side is large.)2 driving
cyclesNot
applicable
P0300
P0301
P0302
P0303
P0304
P0305
P0306Random misfire detected
Cylinder 1 misfire detected
Cylinder 2 misfire detected
Cylinder 3 misfire detected
Cylinder 4 misfire detected
Cylinder 5 misfire detected
Cylinder 6 misfire detectedMisfire of such level as to cause dam-
age to three way catalystMIL flashing
during mis-
fire detec-
tionNot
applicable
Misfire of such level as to deteriorate
emission but not to cause damage to
three way catalyst2 driving
cyclesNot
applicable
P0325
(No.43)Knock sensor circuit malfunc-
tionSensor output too low
1 driving
cycle1 driving
cycle
Sensor output too high
P0335Crankshaft position sensor cir-
cuit malfunctionNo signal during engine running and
CMP sensor signal inputting1 driving
cycleNot
applicable
P0340
(No.42)Camshaft position sensor cir-
cuit malfunctionNo signal for 3 sec. during engine
cranking, REF signal pattern incor-
rect or POS signal voltage too high or
too low1 driving
cycleNot
applicable
P0400Exhaust gas recirculation flow
malfunction detectedExcessive or insufficient EGR flow.2 driving
cyclesNot
applicable
P0403
(No.51)EGR valve circuit malfunctionEGR valve electrical circuit open or
shot to ground1 driving
cycle1 driving
cycle
P0420Catalyst system efficiency
below threshold (Bank 1)Output waveforms of HO2S-1 and
HO2S-2 are similar.
(Time from output voltage change of
HO2S-1 to that of HO2S-2 is shorter
than specification.)2 driving
cyclesNot
applicable
P0430Catalyst system efficiency
below threshold (Bank 2)Output waveforms of HO2S-1 and
HO2S-2 are similar.
(Time from output voltage change of
HO2S-1 to that of HO2S-2 is shorter
than specification.)2 driving
cyclesNot
applicable
P0443Purge control valve circuit
malfunctionPurge control valve circuit is open or
shorted to ground.2 driving
cyclesNot
applicable
P0500
(No.24)Vehicle speed sensor mal-
functionNo signal while running in “D” range
or during fuel cut at decelerating.2 driving
cycles1 driving
cycle DTC NO. DETECTED ITEMDETECTING CONDITION
(DTC will set when detecting : )MIL
(vehicle
without
monitor
connector)MIL
(vehicle
with
monitor
connector)

6-1-80 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306 Random Misfire/Cylinder
1 Misfire/Cylinder 2 Misfire/Cylinder 3 Misfire/Cylinder 4 Misfire Detected/Cyl-
inder 5 Misfire Detected/Cylinder 6 Misfire Detected
SYSTEM DESCRIPTION
ECM (PCM) measures the angle speed of the crankshaft based on the pulse signal from the CKP sensor and
CMP sensor for each cylinder. If it detects a large change in the angle speed of the crankshaft, it concludes
occurrence of a misfire. When the number of misfire is counted by the ECM (PCM) beyond the DTC detecting
condition, it determines the cylinder where the misfire occurred and outputs it as DTC.
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and start
engine.
3) Increase vehicle speed to speed recorded as freeze frame data (V) ± 5 km/h when detecting misfire.
4) Keep driving above vehicle speed for 5 min.
5) Stop vehicle and check DTC (or pending DTC) by using scan tool.DTC DETECTING CONDITION TROUBLE AREA
DTC P0300 :
• Misfire which causes catalyst to overheat during 200 engine
revolutions is detected at 2 or more cylinders. (MIL flashes as
long as this misfire occurs continuously.)
• Misfire which affects exhaust emission adversely during 1000
engine revolutions is detected at 2 or more cylinders (2 driving
cycle detection logic)• Ignition system
• Fuel injector and its circuit
• Fuel line pressure
• Engine compression
• Abnormal air drawn in
• EGR system
• Fuel level sensor
• Valve lash adjuster
• Valve timing DTC P0301, P0302, P0303, P0304, P0305, P0306 :
• Misfire which causes catalyst to overheat during 200 engine
revolutions is detected at 1 cylinder. (MIL flashes as long as
this misfire occurs continuously.)
• Misfire which affects exhaust emission adversely during 1000
engine revolutions is detected at 1 cylinder
(2 driving cycle detection logic)
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent 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.
NOTE:
Check to make sure that following conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
Intake air temp. : – 8 – 70°C (18 – 158°F)
Engine coolant temp. : – 8°C (18°F) or higher
Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)

AUTOMATIC TRANSMISSION (4 A/T) 7B1-9
Precaution in Diagnosing Trouble
•Don’t disconnect couplers from PCM (ECM), battery cable
from battery, PCM ground wire harness from engine or main
fuse before checking the diagnosis information (DTC, freeze
frame data, etc.) stored in PCM memory. Such disconnec-
tion will clear memorized information in PCM memory.
•Using SUZUKI scan tool or also generic scan tool for vehicle
without monitor connector, the diagnostic information stored
in PCM memory can be checked and cleared as well. Before
its use, be sure to read Operator’s (Instruction) Manual sup-
plied with it carefully to have good understanding of its func-
tions and usage.
•Priorities for diagnosing troubles
If two or more diagnostic trouble codes (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 diagnostic trouble
codes according to the following priorities.
–Diagnostic trouble codes (DTCs) other than DTC P0171/
P0172/P0174/P0175 (Fuel system too lean/too rich), DTC
P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire
detected) and DTC P0400 (EGR flow malfunction)
–DTC P0171/P0172/P0174/P0175 (Fuel system too lean/too
rich) and DTC P0400 (EGR flow malfunction)
–DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306
(Misfire detected)
•Be sure to read “PRECAUTIONS FOR ELECTRICAL CIR-
CUIT SERVICE” in Section 0A before inspection and
observe what is written there.
•PCM replacement
When substituting a known-good PCM, check for following
conditions.
Neglecting this check may result in damage to a good PCM.
–All relays and actuators have resistance of specified value.
–MAF sensor, MDP sensor, TP sensor and fuel tank pres-
sure sensor are in good condition. Also, the power circuit of
these sensors is not shorted to the ground.