6-2 ENGINE GENERAL INFORMATION AND DIAGNOSIS
ENGINE DIAGNOSIS ......................................... 6-6
GENERAL DESCRIPTION ............................. 6-6
ON-BOARD DIAGNOSTIC SYSTEM
(VEHICLE WITH IMMOBILIZER INDICATOR
LAMP) ............................................................. 6-7
ON-BOARD DIAGNOSTIC SYSTEM
(VEHICLE WITHOUT IMMOBILIZER
INDICATOR LAMP) ...................................... 6-10
PRECAUTION IN DIAGNOSING
TROUBLE ..................................................... 6-11
ENGINE DIAGNOSTIC FLOW TABLE ......... 6-12
CUSTOMER PROBLEM INSPECTION
FORM (EXAMPLE) ................................... 6-14
MALFUNCTION INDICATOR LAMP (MIL)
CHECK...................................................... 6-15
DIAGNOSTIC TROUBLE CODE (DTC)
CHECK...................................................... 6-15
DIAGNOSTIC TROUBLE CODE (DTC)
CLEARANCE ............................................ 6-16
DIAGNOSTIC TROUBLE CODE (DTC)
TABLE ....................................................... 6-17
FAIL-SAFE TABLE.................................... 6-20
VISUAL INSPECTION .............................. 6-22
ENGINE BASIC INSPECTION.................. 6-23
ENGINE DIAGNOSIS TABLE ................... 6-26
SCAN TOOL DATA....................................... 6-31
INSPECTION OF ECM AND ITS
CIRCUITS ..................................................... 6-36
ECM VOLTAGE VALUES TABLE............. 6-37
TERMINAL RESISTANCE TABLE............ 6-43
COMPONENT LOCATION ........................... 6-45
TABLE A-1 MALFUNCTION INDICATOR
LAMP CIRCUIT CHECK - LAMP DOES NOT
COME “ON” AT IGNITION SWITCH ON
(BUT ENGINE AT STOP) ............................. 6-46
TABLE A-2 MALFUNCTION INDICATOR
LAMP CIRCUIT CHECK - LAMP REMAINS
“ON” AFTER ENGINE STARTS ................... 6-47
TABLE A-3 MIL CHECK - MIL FLASHES
AT IGNITION SWITCH ON (VEHICLE
WITHOUT IMMOBILIZER INDICATOR
LAMP) ........................................................... 6-48
TABLE A-4 MIL CHECK - MIL DOES NOT
FLASH OR JUST REMAINS ON EVEN
WITH GROUNDING DIAGNOSIS SWITCH
TERMINAL (VEHICLE WITHOUT
IMMOBILIZER INDICATOR LAMP) .............. 6-48
TABLE A-5 ECM POWER AND GROUND
CIRCUIT CHECK - MIL DOESN’T LIGHT
AT IGNITION SWITCH ON AND ENGINE
DOESN’T START THOUGH IT IS
CRANKED UP .............................................. 6-49
DTC P0105 (DTC NO.11) MANIFOLD
ABSOLUTE PRESSURE (MAP) CIRCUIT
MALFUNCTION ............................................ 6-52
DTC P0110 (DTC NO.18) INTAKE AIR
TEMP. (IAT) CIRCUIT MALFUNCTION ....... 6-55
DTC P0115 (DTC NO.19) ENGINE
COOLANT TEMPERATURE (ECT) CIRCUIT
MALFUNCTION ............................................ 6-57DTC P0120 (DTC NO.13) THROTTLE
POSITION CIRCUIT MALFUNCTION ........... 6-60
DTC P0121 THROTTLE POSITION CIRCUIT
RANGE/PERFORMANCE PROBLEM .......... 6-63
DTC P0130 (DTC NO.14) HEATED OXYGEN
SENSOR (HO2S) CIRCUIT MALFUNCTION
(SENSOR-1) .................................................. 6-66
DTC P0133 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT SLOW RESPONSE
(SENSOR-1) .................................................. 6-68
DTC P0134 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT NO ACTIVITY DETECTED
(SENSOR-1) .................................................. 6-69
DTC P0135 (DTC NO.14) HEATED OXYGEN
SENSOR (HO2S) HEATER CIRCUIT
MALFUNCTION (SENSOR-1) ....................... 6-70
DTC P0136 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT MALFUNCTION
(SENSOR-2) .................................................. 6-72
DTC P0141 HEATED OXYGEN SENSOR
(HO2S) HEATER CIRCUIT MALFUNCTION
(SENSOR-2) .................................................. 6-74
DTC P0171 FUEL SYSTEM TOO LEAN ....... 6-76
DTC P0172 FUEL SYSTEM TOO RICH ....... 6-76
DTC P0300 RANDOM MISFIRE DETECTED
(MISFIRE DETECTED AT 2 OR MORE
CYLINDERS) ................................................. 6-81
DTC P0301 CYLINDER 1 MISFIRE
DETECTED ................................................... 6-81
DTC P0302 CYLINDER 2 MISFIRE
DETECTED ................................................... 6-81
DTC P0303 CYLINDER 3 MISFIRE
DETECTED ................................................... 6-81
DTC P0304 CYLINDER 4 MISFIRE
DETECTED ................................................... 6-81
DTC P0325 (DTC NO.17) KNOCK SENSOR
CIRCUIT MALFUNCTION ............................. 6-86
DTC P0335 (DTC NO.23) CRANKSHAFT
POSITION (CKP) SENSOR CIRCUIT
MALFUNCTION ............................................. 6-88
DTC P0340 (DTC NO.15) CAMSHAFT
POSITION (CMP) SENSOR CIRCUIT
MALFUNCTION ............................................. 6-91
DTC P0400 EXHAUST GAS
RECIRCULATION FLOW MALFUNCTION ... 6-94
DTC P0420 CATALYST SYSTEM
EFFICIENCY BELOW THRESHOLD ............ 6-97
DTC P0443 PURGE CONTROL VALVE
CIRCUIT MALFUNCTION ........................... 6-100
DTC P0480 RADIATOR COOLING FAN
CONTROL SYSTEM MALFUNCTION ........ 6-101
DTC P0500 (DTC NO.16) VEHICLE SPEED
SENSOR (VSS) MALFUNCTION ................ 6-103
DTC P0505 (DTC NO.26) IDLE CONTROL
SYSTEM MALFUNCTION ........................... 6-105
DTC P1450 BAROMETRIC PRESSURE
SENSOR LOW/HIGH INPUT....................... 6-108
DTC P1451 BAROMETRIC PRESSURE
SENSOR PERFORMANCE PROBLEM ...... 6-108
6-6 ENGINE GENERAL INFORMATION AND DIAGNOSIS
FUEL PRESSURE RELIEF PROCEDURE
After making sure that engine is cold, release fuel pressure as fol-
lows.
1) Place transmission gear shift lever in “Neutral” (Shift selector
lever to “P” range for A/T model), set parking brake, and
block drive wheels.
2) Remove relay box cover.
3) Disconnect fuel pump relay (1) from relay box.
4) Remove fuel filler cap to release fuel vapor pressure in fuel
tank and then reinstall it.
5) Start engine and run it till it stops for lack of fuel. Repeat
cranking engine 2-3 times for about 3 seconds each time to
dissipate fuel pressure in lines. Fuel connections are now
safe for servicing.
6) Upon completion of servicing, connect fuel pump relay (1) to
relay box and install relay box cover.
FUEL LEAKAGE CHECK PROCEDURE
After performing any service on fuel system, check to make sure
that there are no fuel leakages as follows.
1) Turn ON ignition switch for 3 seconds (to operate fuel pump)
and then turn it OFF.
Repeat this (ON and OFF) 3 or 4 times and apply fuel pres-
sure to fuel line. (till fuel pressure is felt by hand placed on
fuel feed hose.)
2) In this state, check to see that there are no fuel leakages
from any part of fuel system.
ENGINE DIAGNOSIS
GENERAL DESCRIPTION
This vehicle is equipped with an engine and emission control system which are under control of ECM.
The engine and emission control system in this vehicle are controlled by ECM. ECM has an On-Board Diagnos-
tic system which detects a malfunction in this system and abnormality of those parts that influence the engine
exhaust emission. When diagnosing engine troubles, be sure to have full understanding of the outline of “On-
Board Diagnostic System” and each item in “Precaution in Diagnosing Trouble” and execute diagnosis accord-
ing to “ENGINE DIAGNOSTIC FLOW TABLE”.
There is a close relationship between the engine mechanical, engine cooling system, ignition system, exhaust
system, etc. and the engine and emission control system in their structure and operation. In case of an engine
trouble, even when the malfunction indicator lamp (MIL) doesn’t turn ON, it should be diagnosed according to
this flow table.CAUTION:
This work must not be done when engine is hot. If done
so, it may cause adverse effect to catalyst.
1
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-7
ON-BOARD DIAGNOSTIC SYSTEM (VEHICLE
WITH IMMOBILIZER INDICATOR LAMP)
ECM in this vehicle has following functions.
When the ignition switch is turned ON with the engine at a
stop, malfunction indicator lamp (MIL) (1) turns ON to check
the bulb of the malfunction indicator lamp (1).
When ECM detects a malfunction which gives an adverse
effect to vehicle emission while the engine is running, it
makes the malfunction indicator lamp (1) in the meter cluster
of the instrument panel turn ON or flash (flashing only when
detecting a misfire which can cause damage to the catalyst)
and stores the malfunction area in its memory.
(If it detects that continuously 3 driving cycles are normal
after detecting a malfunction, however, it makes MIL (1) turn
OFF although DTC stored in its memory will remain.)
As a condition for detecting a malfunction in some areas in
the system being monitored by ECM and turning ON the
malfunction indicator lamp (1) due to that malfunction, 2 driv-
ing cycle detection logic is adopted to prevent erroneous
detection.
When a malfunction is detected, engine and driving condi-
tions then are stored in ECM memory as freeze frame data.
(For the details, refer to description on Freeze frame data.)
It is possible to communicate by using not only SUZUKI scan
tool (Tech-1) (2) but also generic scan tool. (Diagnostic infor-
mation can be accessed by using a scan tool.)
WARM-UP CYCLE
A warm-up cycle means sufficient vehicle operation such that the
coolant temperature has risen by at least 22°C (40°F) from
engine starting and reaches a minimum temperature of 70°C
(160°F).
DRIVING CYCLE
A “Driving Cycle” consists of engine startup, driving mode where
a malfunction would be detected if present, and engine shutoff.
2 DRIVING CYCLES DETECTION LOGIC
The malfunction detected in the first driving cycle is stored in
ECM memory (in the form of pending DTC and freeze frame data)
but the malfunction indicator lamp does not light at this time. It
lights up at the second detection of same malfunction also in the
next driving cycle.
PENDING DTC
Pending DTC means a DTC detected and stored temporarily at
the first driving cycle of the DTC which is detected in the 2 driving
cycle detection logic.
3. Immobilizer indicator lamp
ODO TRIP AB
3 1
2
6-10 ENGINE GENERAL INFORMATION AND DIAGNOSIS
ON-BOARD DIAGNOSTIC SYSTEM (VEHICLE
WITHOUT IMMOBILIZER INDICATOR LAMP)
ECM diagnosis troubles which may occur in the area including
the following parts when the ignition switch is ON and the engine
is running, and indicates the result by turning on or flashing mal-
function indicator lamp (1).
Heated oxygen sensor (if equipped)
ECT sensor
TP sensor
IAT sensor
MAP sensor
CMP sensor
CKP sensor
Knock sensor (if equipped)
VSS
CPU (Central Processing Unit) of ECM
ECM and malfunction indicator lamp (1) operate as follows.
Malfunction indicator lamp (1) lights when the ignition switch
is turned ON (but the engine at stop) with the diagnosis
switch terminal ungrounded regardless of the condition of
Engine and Emission control system. This is only to check
the malfunction indicator lamp (1) bulb and its circuit.
If the above areas of Engine and Emission control system
are free from any trouble after the engine start (while engine
is running), malfunction indicator lamp (1) turns OFF.
When ECM detects a trouble which has occurred in the
above areas, it makes malfunction indicator lamp (1) turn ON
while the engine is running to warn the driver of such occur-
rence of trouble and at the same time it stores the trouble
area in ECM back-up memory. (The memory is kept as it is
even if the trouble was only temporary and disappeared
immediately. And it is not erased unless the power to ECM is
shut off for specified time below.)
ECM also indicates trouble area in memory by means of
flashing of malfunction indicator lamp (1) at the time of
inspection. (i.e. when diagnosis switch terminal (2) is con-
nected to ground terminal (3) with a service wire and ignition
switch is turned ON.)
NOTE:
When a trouble occurs in the above areas and disap-
pears soon while the diagnosis switch terminal is
ungrounded and the engine is running, malfunction
indicator lamp (1) lights and remains ON as long as the
trouble exists but it turns OFF when the normal condi-
tion is restored.
Time required to erase diagnostic trouble code mem-
ory thoroughly varies depending on ambient tempera-
ture as follows.
ODO TRIP AB
1
32
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-15
MALFUNCTION INDICATOR LAMP (MIL) CHECK
1) Turn ON ignition switch (but the engine at stop) and check
that MIL lights.
If MIL does not light up (or MIL dims), go to “Diagnostic Flow
Table A-1” for troubleshooting.
If MIL flushes, go to “Diagnostic Flow Table A-3” (vehicle
without immobilizer indicator lamp).
2) Start engine and check that MIL turns OFF.
If MIL remains ON and no DTC is stored in ECM, go to
“Diagnostic Flow Table A-2” for troubleshooting.
DIAGNOSTIC TROUBLE CODE (DTC) CHECK
[Using SUZUKI Scan Tool]
1) Prepare SUZUKI scan tool (Tech-1).
2) With ignition switch OFF, connect it to data link connector
(DLC) (1) located on underside of instrument panel at
driver’s seat side.
Special tool
(A) : SUZUKI scan tool
(B) : Mass storage cartridge
(C) : 16/14 pin DLC cable
3) Turn ignition switch ON and confirm that MIL lights.
4) Read DTC, pending DTC and freeze frame data according to
instructions displayed on scan tool and print it or write it
down.
Refer to scan tool operator’s manual for further details.
If communication between scan tool and ECM is not possi-
ble, check if scan tool is communicable by connecting it to
ECM in another vehicle. If communication is possible in this
case, scan tool is in good condition. Then check data link
connector and serial data line (circuit) in the vehicle with
which communication was not possible.
5) After completing the check, turn ignition switch off and dis-
connect scan tool from data link connector.
ODO TRIP AB
1
(A)
(B) (C)
6-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS
FAIL-SAFE TABLE
When any of the following DTCs is detected, ECM enters fail-safe mode as long as malfunction continues to
exist but that mode is canceled when ECM detects normal condition after that.P1620
(No.84)ECU code not registered
Refer to Section 8G P1621
(No.83)No ECU code transmitted from Immobilizer
Control Module
P1622
(No.82)Fault in ECM
P1623
(No.81)ECU code not matched DTC NO. DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
NOTE:
For (
) marked No. in DTC column, it is used for vehicle without immobilizer indication lamp.
DTC No.12 appears when none of the other codes is identified.
For vehicle with immobilizer indication lamp, star (
✱) marked DTCs can be read with SUZUKI scan
tool ECM application.
DTC NO. TROUBLE AREA FAIL-SAFE OPERATION SYMPTOM
P0105
(No.11)MAP SENSOR ECM uses value determined by throt-
tle opening and engine speed.
ECM stops EGR, EVAP purge and
idle air control.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation/ poor acceleration/
surge/ detonation or spark knock
P0110
(No.18)IAT SENSOR ECM controls actuators assuming
that intake air temperature is 20°C.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation poor acceleration/ deto-
nation or spark knock
P0115
(No.19)ECT SENSOR ECM controls actuators assuming
that engine coolant temperature is
80°C.
Radiator fan motor ON.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation poor acceleration/ deto-
nation or spark knock
P0120
(No.13)TP SENSOR ECM controls actuators assuming
that throttle opening is 20°.Rough or incorrect idle/ excessive
fuel consumption/ hesitation/ poor
acceleration
P0130,
P0134
(No.14)HEATED OXYGEN
SENOR-1–Hard starting/rough or incorrect
idle/ excessive fuel consumption/
hesitation/ poor acceleration
P0325
(No.17)KNOCK SENSOR–Detonation/ spark knock
P0335
(No.23)CKP SENSORFix ignition timing.
ECM changes injection control sys-
tem from sequential injection to
simultaneous one.Hard staring/ engine stall
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-21
P0340
(No.15)CMP SENSOR ECM changes injection control sys-
tem from sequential injection to simul-
taneous one.Hard starting
P0400 EGR VALVE–Hard starting/rough or incorrect
idle/ excessive fuel consumption/
hesitation/ poor acceleration/
surge/ detonation or spark knock/
engine stall
P0420 CATALYST––
P0443 PURGE CONTROL
VALVE–Rough or incorrect idle/ surge/
hard starting/ engine stall
P0480 RADIATOR FAN
CONTROL SYSTEM–Engine overheating
P0500
(No.16)VEHICLE SPEED
SENSORECM stops idle air control. Rough or incorrect idle
P0505 IDLE CONTROL
SYSTEM–Engine stall/ rough or incorrect idle
P0601
(No.71)ECM INTERNAL–Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
detonation or spark knock/ hesita-
tion poor acceleration/
P1450
(No.29)BAROMETRIC
PRESSURE SEN-
SORECM controls actuators assuming
that barometric pressure is
100 kPa (760 mmHg).Hard starting/ rough or incorrect
idle DTC NO. TROUBLE AREA FAIL-SAFE OPERATION SYMPTOM
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-23
ENGINE BASIC INSPECTION
This check is very important for troubleshooting when ECM has detected no DTC and no abnormality has been
found in visual inspection.
Follow the flow table carefully.
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Check battery voltage.
Is it 11 V or more?Go to Step 3. Charge or replace battery.
3 Is engine cranked? Go to Step 4. Go to “DIAGNOSIS” in
Section 6G.
4 Does engine start? Go to Step 5. Go to Step 7.
5 Check idle speed as follows :
1) Warm up engine to normal operating temp.
2) Shift transmission to neutral position for M/T
(“P” position for A/T).
3) All of electrical loads are switched off.
4) Check engine idle speed with scan tool.
See Fig. 1.
Is it 650 – 750 r/min (700 – 800 r/min. for A/T
vehicle)?Go to Step 6. Go to “ENGINE DIAGNO-
SIS TABLE”.
6 Check ignition timing as follows :
1) When SUZUKI scan tool is not available,
disconnect scan tool from DLC and connect
test switch terminal of monitor connector to
ground. See Fig. 2.
When using SUZUKI scan tool, select
“MISC” mode on SUZUKI scan tool and fix
ignition timing to initial one. See Fig. 3.
2) Using timing light (1), check initial ignition
timing. See Fig. 4.
Is it 5° ± 3° BTDC at specified idle speed?Go to “ENGINE DIAGNO-
SIS TABLE”.Check ignition control
related parts referring to
Section 6F1.
7 Is immobilizer control system equipped? Go to Step 8. Go to Step 9.
8 Check immobilizer system malfunction as fol-
lows.
1) Check immobilizer indicator lamp or MIL
(malfunction indicator lamp) for flashing.
Is it flashing when ignition switch is turned to
ON position?Go to “DIAGNOSIS” in
Section 8G.Go to Step 9.
9 Check fuel supply as follows :
1) Check to make sure that enough fuel is
filled in fuel tank.
2) Turn ON ignition switch for 2 seconds and
then OFF. See Fig. 5.
Is fuel pressure felt from fuel feed hose (1)
when ignition switch is turned ON?Go to Step 11. Go to Step 10.
10 Check fuel pump for operating.
Was fuel pump operating sound heard from fuel
filler for about 10 seconds after ignition switch
ON and stop?Go to “DIAG. FLOW
TABLE B-3”.Go to “DIAG. FLOW
TABLE B-2”.