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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 its connector.
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
its connector.
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. CAUTION:
This work must not be done when engine is hot. If done
so, it may cause adverse effect to catalyst.
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P0335
(No.23)Crankshaft position sensor
circuit malfunctionNo signal for 2 sec. During engine crank-
ing1 driving
cycle1 driving
cycle
P0340
(No.15)Camshaft position sensor
circuit malfunctionNo signal during engine running1 driving
cycle1 driving
cycle
P0400Exhaust gas recirculation
flow malfunction detectedExcessive or insufficient EGR flow2 driving
cyclesNot
applicable
P0420Catalyst system efficiency
below thresholdOutput 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 ground2 driving
cyclesNot
applicable
P0481A/C condenser fan control
circuit malfunctionA/C condenser fan relay terminal voltage is
low when fan command is not outputted2 driving
cyclesNot
applicable
P0500
(No.16)Vehicle speed sensor mal-
functionNo signal while running in “D” range or
during fuel cut at decelerating2 driving
cycles1 driving
cycle
P0505 Idle control system malfunc-
tionNo closed signal to IAC valve is detected2 driving
cyclesNot
applicable
P0601
(No.71)Internal control module
memory check sum errorData write error (or check sum error) when
written into ECM2 driving
cyclesNot
applicable
P1450 Barometric pressure sen-
sor circuit malfunctionBarometric pressure is lower or higher
than specification. (or sensor malfunction)1 driving
cycleNot
applicable
P1451Barometric pressure sen-
sor performance problemDifference between manifold absolute
pressure (MAP sensor value) and baro-
metric pressure (barometric pressure sen-
sor value) is larger than specification
during cranking.2 driving
cyclesNot
applicable
P1500Starter signal circuit mal-
functionStarter signal is not inputted from engine
cranking till its start and after or it is always
inputted2 driving
cyclesNot
applicable
P1510ECM backup power source
malfunctionNo backup power after starting engine1 driving
cycleNot
applicable
P1600Serial communication prob-
lem between ECM and
TCMNo signal or check sum error while engine
running1 driving
cycleNot
applicable
P1717AT D-range signal circuit
malfunctionNo “D” range (park / neutral position sig-
nal) is inputted while vehicle running2 driving
cyclesNot
applicable
P1570ABS signal circuit malfunc-
tionABS signal ON (low voltage) when engine
startNot
applicable1 driving
cycle DTC
NO.DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
(vehicle
with immo-
bilizer indi-
cator lamp)MIL
(vehicle
without
immobi-
lizer indica-
tor lamp)
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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.
DTC NO. DETECTED ITEM FAIL-SAFE OPERATION (SYMPTOM)
P0105
(No.11)Manifold absolute pressure sensor circuit
malfunctionECM uses value determined by throttle opening and
engine speed.
P0110
(No.18)Intake air temp. sensor circuit malfunctionECM controls actuators assuming that intake air tem-
perature is 20 °C (68 °F).
P0115
(No.19)Engine coolant temp. sensor circuit mal-
functionECM controls actuators assuming that engine coolant
temperature is 80 °C (176 °F).
P0120
(No.13)Throttle position sensor circuit malfunc-
tionECM controls actuators assuming that throttle opening
is 20°. (High idle speed)
P0335
(No.23)Crankshaft position sensor circuit mal-
functionECM controls injection system sequential injection to
synchronous injection. (Cranking for a few seconds to
start engine)
P0340
(No.15)Camshaft position sensor circuit malfunc-
tionECM controls injection system sequential injection to
synchronous injection. (Cranking for a few seconds to
start engine)
P0500
(No.16)Vehicle speed sensor malfunction ECM stops idle air control.
P1450Barometric pressure sensor low / high
inputECM controls actuators assuming that barometric
pressure is 100 kPa (760 mmHg).
P1570
(No.21)ABS signal circuit malfunctionECM controls actuators assuming that ABS signal is
OFF.
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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” performed? 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 Sec-
tion 6G.
4 Does engine start? Go to Step 5. Go to Step 9.
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 Diagnosis
Table”.
6 Is SUZUKI scan tool available? Go to Step 8. Go to Step 7.
7 Check ignition timing as follows :
1) Connect test switch terminal (2) of monitor
coupler (1) to ground. See Fig. 2.
2) Remove air cleaner bolt and crips and shift
air cleaner position to observe ignition tim-
ing.
3) Using timing light (1), check initial ignition
timing.
See Fig. 4.
Is it 5° ± 3° BTDC at specified idle speed?Go to “Engine Diagnosis
Table”.Check ignition control
related parts referring to
Section 6F.
8 Check ignition timing as follows :
1) Select “MISC” mode on SUZUKI scan tool
and fix ignition timing to initial one. See Fig.
3.
2) Remove air cleaner bolt and crips and shift
air cleaner position to observe ignition tim-
ing.
3) Using timing light (1), check initial ignition
timing. See Fig. 4.
Is it 5° ± 3° BTDC at specified idle speed?Go to “Engine Diagnosis
Table”.Check ignition control
related parts referring to
Section 6F.
9 Check immobilizer system malfunction as fol-
lows (if equipped) :
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 Sec-
tion 8G.Go to Step 10.
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[A] Fig. 1 for Step 5 / [B] Fig. 2 for Step 7 / [C] Fig. 3 for Step 810 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 return pressure (returning sounds) felt
from fuel feed hose (1) when ignition switch is
turned ON?Go to Step 12. Go to Step 11.
11 Check fuel pump for operating.
1) Was fuel pump operating sound heard from
fuel filler for about 2 seconds after ignition
switch ON and stop?Go to “Diag. Flow Table
B-3”.Go to “Diag. Flow Table
B-2”.
12 Check ignition spark as follows :
1) Disconnect injector couplers.
2) Remove spark plugs and connect them to
high tension cords.
3) Ground spark plugs.
4) Crank engine and check if each spark plug
sparks.
Is it in good condition?Go to Step 13. Go to “Ignition Spark Test”
in Section 6F.
13 Check fuel injector for operation as follows :
1) Install spark plugs and connect injector con-
nectors.
2) Using sound scope (2), check operating
sound of each injector (3) when cranking
engine. See Fig. 6.
Was injector operating sound heard from all
injectors?Go to “Engine Diagnosis
Table”.Go to “Diag. Flow Table
B-1”. Step Action Yes No
[B] : When not using SUZUKI scan tool :
[C] : When using SUZUKI scan tool
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[D] Fig. 4 for Step 7 or 8 / [E] Fig. 5 for Step 10 / [F] Fig. 6 for Step 13
Engine diagnosis table
Perform troubleshooting referring to following table when ECM has no DTC and no abnormality found in visual
inspection and engine basic inspection previously.
Condition Possible Cause Reference Item
Hard Starting
(Engine cranks OK)Faulty ignition coil Ignition coil assembly in Section 6F.
Faulty CMP sensing rotor or CKP sensing
rotorCMP sensing rotor or CKP sensing
rotor inspection in Section 6E.
Faulty idle air control system Diagnostic Flow Table B-4
Faulty ECT sensor, TP sensor, CKP sen-
sor, CMP sensor or MAP sensorECT sensor, TP sensor, CKP sensor,
CMP sensor or MAP sensor in Sec-
tion 6E.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty fuel injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning PCV system PCV system in Section 6E.
Low compression Compression check in Section 6A1.
Improper valve lash Valve lash in Section 6A1.
Improper valve timing Timing chain and chain tensioner in
Section 6A1.
Compression leak from valve seat Valves and cylinder head in Section
6A1.
Sticky valve stem Valves and cylinder head in Section
6A1.
Weak or damaged valve springs Valves and cylinder head in Section
6A1.
Compression leak at cylinder head gasket Valves and cylinder head in Section
6A1.
Sticking or damaged piston ring Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Worn piston, ring or cylinder Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
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Excessive engine oil
consumptionSticky piston ring Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Worn piston and cylinder Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Worn piston ring groove and ring Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Improper location of piston ring gap Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Worn or damaged valve stem seal Valves and cylinder head in Section
6A1.
Worn valve stem Valves and cylinder head in Section
6A1.
Low oil pressure
Improper oil viscosity ITEM1-3 Engine oil and oil filter
change in Section 0B.
Malfunctioning oil pressure switch Oil pressure switch in Section 8.
Clogged oil strainer Oil pan and oil pump strainer in Sec-
tion 6A1.
Functional deterioration of oil pump Oil pump in Section 6A1.
Worn oil pump relief valve Oil pump in Section 6A1.
Excessive clearance in various sliding
partsRefer to Section 6A1.
Engine noise
See NOTE below.Improper valve lash Valve lash in Section 6A1.
Worn valve stem and guide Valves and cylinder head in Section
6A1.
Weak or broken valve spring Valve springs in Section 6A1.
Warped or bent valve Valves and cylinder head in Section
6A1.
Loose camshaft housing bolts Camshaft in Section 6A1.
Worn piston, ring and cylinder bore Pistons and cylinders in Section 6A1.
Worn crankpin bearing Crankpin and connecting rod bearing
in Section 6A1.
Worn crankpin Crankpin and connecting rod bearing
in Section 6A1.
Loose connecting rod nuts Connecting rod in Section 6A1.
Low oil pressure Previously outlined.
Worn crankshaft journal bearing Main bearings, Crankshaft and cylin-
der block in Section 6A1.
Worn crankshaft journal Main bearings, Crankshaft and cylin-
der block in Section 6A1.
Loose lower crankcase (bearing cap) bolts Main bearings, Crankshaft and cylin-
der block in Section 6A1.
Excessive crankshaft thrust play Main bearings, Crankshaft and cylin-
der block in Section 6A1. Condition Possible Cause Reference Item
NOTE:
Before checking the mechanical noise, make sure that :
Ignition timing is properly adjusted.
Specified spark plug is used.
Specified fuel is used.
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Scan tool data definitions
FUEL SYSTEM (FUEL SYSTEM STATUS)
Air / fuel ratio feedback loop status displayed as either open or closed loop. Open indicates that ECM ignores
feedback from the exhaust oxygen sensor.
Closed indicates final injection duration is corrected for oxygen sensor feedback.
CALC LOAD (CALCULATED LOAD VALUE, %)
Engine load displayed as a percentage of maximum possible load. Value is calculated mathematically using the
formula : actual (current) intake air volume ÷ maximum possible intake air volume x 100%.
COOLANT TEMP. (ENGINE COOLANT TEMPERATURE, °C, °F)
It is detected by engine coolant temp. sensor
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
Short term fuel trim value represents short term corrections to the air / fuel mixture computation. A value of 0
indicates no correction, a value greater than 0 means an enrichment correction, and a value less than 0 implies
an enleanment correction.
LONG FT B1 (LONG TERM FUEL TRIM, %)
Long term fuel trim Value represents long term corrections to the air / fuel mixture computation. A value of 0 indi-
cates no correction, a value greater than 0 means an enrichment correction, and a value less than 0 implies an
enleanment correction.
MAP (INTAKE MANIFOLD ABSOLUTE PRESSURE, kPa, inHg)
It is detected by manifold absolute pressure sensor and used (among other things) to compute engine load.
ENGINE SPEED (rpm)
It is computed by reference pulses from crankshaft position sensor.
VEHICLE SPEED (km/h, MPH)
It is computed based on pulse signals from vehicle speed sensor.
IGNITION ADVANCE (IGNITION TIMING ADVANCE FOR NO.1 CYLINDER, °)
Ignition timing of NO.1 cylinder is commanded by ECM. The actual ignition timing should be checked by using
the timing light.
INTAKE AIR TEMP. (°C, °F)
It is detected by intake air temp. sensor and used to determine the amount of air passing into the intake manifold
as air density varies with temperature.
MAF (MASS AIR FLOW RATE, gm/s, lb/min)
It represents total mass of air entering intake manifold which is computed based on signals from MAP sensor,
IAT sensor, TP sensor, etc.BRAKE SWIgnition switch
ONBrake pedal is depressing ON
Brake pedal is releasing OFF
BLOWER FANIgnition switch
ONBlower fan switch ON ON
Blower fan switch OFF OFF
A/C MAG CLUTCHIgnition switch
ONA/C operating ON
A/C not operating OFF SCAN TOOL DATA CONDITION REFERENCE VALUES