Downloaded from www.Manualslib.com manuals search engine 6-10 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Precaution in Diagnosing Trouble
Don’t disconnect couplers from ECM, battery cable at battery, ECM ground wire harness from engine or
main fuse before confirming diagnostic information (DTC, freeze frame data, etc.) stored in ECM memory.
Such disconnection will erase memorized information in ECM memory.
Diagnostic information stored in ECM 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 with Immobilizer indicator lamp).
If multiple diagnostic trouble codes (DTCs) are stored, proceed to the flow table of the DTC which has
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 (Fuel system too lean / too rich), DTC
P0300/P0301/P0302/P0303/P0304 (Misfire detected) and DTC P0400 (EGR flow malfunction)
–DTC P0171/P0172 (Fuel system too lean / too rich) and DTC P0400 (EGR flow malfunction)
–DTC P0300/P0301/P0302/P0303/P0304 (Misfire detected)
Be sure to read “Precautions for Electrical Circuit Service” in Section 0A before inspection and observe what
is written there.
ECM Replacement
When substituting a known-good ECM, check for following conditions. Neglecting this check may cause
damage to a known-good ECM.
–Resistance value of all relays, actuators is as specified respectively.
–MAP sensor and TP sensor are in good condition and none of power circuits of these sensors is shorted
to ground.AMBIENT TEMPERATURE TIME TO CUT POWER TO
ECM
Over 0 °C (32 °F) 60 sec. or longer
Under 0 °C (32 °F)Not specifiable.
Select a place with higher than
0 °C (32 °F) temperature.
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-17
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)
Downloaded from www.Manualslib.com manuals search engine 6-24 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Engine has no power
Engine overheating Refer to “Overheating” of this table.
Faulty ignition coil Ignition coil assembly in Section 6F.
Faulty knock sensor Knock sensor malfunction in this sec-
tion.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty injector Diagnostic Flow Table B-1
Faulty TP sensor, ECT sensor or MAP
sensorTP sensor, ECT sensor or MAP sen-
sor in Section 6E.
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning EGR valve (if equipped) EGR system in Section 6E.
Maladjusted accelerator cable play Accelerator cable adjustment in Sec-
tion 6E.
Low compression Previously outlined.
Dragging brakes Diagnosis table in Section 5.
Slipping clutch Diagnosis table in Section 7C.
Improper engine idling
or engine fails to idleFaulty ignition coil Ignition coil assembly in Section 6F.
Engine overheating Refer to “Overheating” of this table.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty idle air control system Diagnostic Flow Table B-4
Faulty evaporative emission control sys-
temEVAP control system in Section 6E.
Faulty injector Diagnostic Flow Table B-1
Faulty ECT sensor, TP sensor or MAP
sensorECT sensor, TP sensor or MAP sen-
sor in Section 6E.
Malfunctioning PCV system PCV system in Section 6F.
Faulty ECM Inspection of ECM and its circuit in
this section.
Faulty EGR system (if equipped) EGR system in Section 6E.
Low compression Previously outlined.
Engine hesitates
(Momentary lack of
response as the accel-
erator is depressed.
Can occur at all vehicle
speeds.
Usually most severe
when first trying to
make the vehicle move,
as from a stop sign.)Faulty ignition coil Ignition coil assembly in Section 6F.
Engine overheating Refer to “Overheating” of this table.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty injector Diagnostic Flow Table B-1
Faulty TP sensor, ECT sensor or MAP
sensorTP sensor, ECT sensor or MAP sen-
sor in Section 6E.
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning EGR valve (if equipped) EGR system in Section 6E.
Low compression Previously outlined.
Surges
(Engine power variation
under steady throttle or
cruise.
Feels like the vehicle
speeds up and down
with no change in the
accelerator pedal.)Faulty ignition coil or high-tension cord Ignition coil assembly or high-tension
cords in Section 6F.
Variable fuel pressure Diagnostic Flow Table B-3
Faulty MAP sensor MAP sensor in Section 6E.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning EGR valve (if equipped) EGR system in Section 6E. Condition Possible Cause Reference Item
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Excessive detonation
(The engine makes
sharp metallic knocks
that change with throt-
tle opening.
Sounds like pop corn
popping.)Engine overheating Refer to “Overheating” of this table.
Faulty spark plug Spark plugs in Section 6F.
Clogged fuel filter and fuel lines Diagnostic Flow Table B-3
Malfunctioning EGR valve (if equipped) EGR system in Section 6E.
Poor performance of knock sensor, ECT
sensor or MAP sensorKnock sensor in this section, ECT
sensor or MAP sensor in Section 6E.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Excessive combustion chamber deposits Piston and cylinder head in Section
6A1.
Overheating
Inoperative thermostat Thermostat in Section 6B.
Faulty A/C condenser fan motor or its cir-
cuitA/C condenser fan control system
check in Section 6E.
Loose or slip water pump belt ITEM1-1 Drive belt inspection and
change in Section 0B.
Poor water pump performance Water pump in Section 6B.
Clogged or leaky radiator Radiator in Section 6B.
Improper engine oil grade ITEM1-3 Engine oil and oil filter
change in Section 0B.
Clogged oil filter or oil strainer Oil pressure check in Section 6A1.
Poor oil pump performance Oil pressure check in Section 6A1.
Dragging brakes Diagnosis Table in Section 5.
Slipping clutch Diagnosis Table in Section 7C.
Blown cylinder head gasket Valves and cylinder head in Section
6A1.
Poor gasoline mileage
Faulty ignition coil Ignition coil assembly in Section 6F.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty TP sensor, ECT sensor or MAP
sensorTP sensor, ECT sensor or MAP sen-
sor in Section 6E.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning EGR valve (if equipped) EGR system in Section 6E.
High idle speed Refer to item “Improper Engine Idle
Speed” previously outlined.
Low compression Previously outlined.
Poor valve seating Valves and cylinder head in Section
6A1.
Dragging brakes Diagnosis Table in Section 5.
Slipping clutch Diagnosis Table in Section 7C.
Thermostat out of order Thermostat in Section 6B.
Improper tire pressure Refer to Section 3F. Condition Possible Cause Reference Item
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Condition Possible Cause Reference Item
Excessive hydrocar-
bon (HC) emission or
Excessive carbon mon-
oxide (CO) emissionFaulty ignition coil Ignition coil assembly in Section 6F.
Fuel pressure out of specification Diagnostic Flow Table B-3
Lead contamination of three way catalytic
converterMaintenance in Section 6K.
Malfunctioning PCV system PCV system in Section 6E.
Faulty EVAP control system EVAP control system in Section 6E.
Closed loop system (A/F feed back com-
pensation) fails
–Faulty TP sensor
–Faulty ECT sensor or MAP sensor
–Faulty oxygen sensorCheck oxygen sensor output voltage.
Refer to DTC P0130 (No.14) Table in
this section.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Low compression Previously outlined.
Excessive nitrogen
oxides (NOx) emissionFuel pressure out of specification Diagnostic Flow Table B-3
Lead contamination of three way catalytic
converterMaintenance in Section 6K.
Closed loop system (A/F feed back com-
pensation) fails
–Faulty TP sensor
–Faulty ECT sensor or MAP sensor
–Faulty oxygen sensorCheck oxygen sensor output voltage
Refer to DTC P0130 (No.14) Table in
this section.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Faulty EGR system (if equipped) EGR system in Section 6E.
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-29
∆✱
✱✱ ✱O2S B1 S2 (HEATED OXY-
GEN SENSOR-2)When engine is running at 2000 r/min. for
3 min or longer after warming up.0.01 – 0.95 V
∆✱
✱✱ ✱PSP SW No load to power steering. OFF
DESIRED IDLE
(DESIRED IDLE SPEED)At idling with no load after warming up, M/T
at neutral, A/T at “P” rangeM/T 700 r/min
A/T 750 r/min
TP SENSOR VOLT
(THROTTLE POSITION
SENSOR OUTPUT VOLT-
AGE)Ignition switch
ON / engine
stoppedThrottle valve fully closed More than 0.2 V
Throttle valve fully open Less than 4.8 V
INJ PULSE WIDTH (FUEL
INJECTION PULSE
WIDTH)At specified idle speed with no load after
warming up2.0 – 3.6 msec.
At 2500 r/min with no load after warming up 2.0 – 3.6 msec.
IAC FLOW DUTY (IDLE
AIR CONTROL FLOW
DUTY)At idling with no load after warming up 5 – 25 %
TOTAL FT B1 At specified idle speed after warming up– 35 – +35 %
BATTERY VOLTAGE Ignition switch ON / engine stop 12 – 15 V
CANIST PRG DUTY
(EVAP CANISTER PURGE
FLOW DUTY)–0 – 100 %
CLOSED THROT POS
(CLOSED THROTTLE
POSITION)Throttle valve at idle position ON
Throttle valve opens larger than idle posi-
tionOFF
FUEL CUTWhen engine is at fuel cut condition ON
Other than fuel cut condition OFF
A/C CONDENSER FANIgnition switch
ONA/C not operating OFF
A/C operating ON
ELECTRIC LOADIgnition switch ON / Headlight, small light,
heater fan and rear window defogger all
turned OFFOFF
Ignition switch ON / Headlight, small light,
heater fan or rear window defogger turned
ONON
A/C SWITCHEngine running after warming up, A/C not
operatingOFF
Engine running after warming up, A/C oper-
atingON
PNP SIGNAL (PARK / NEU-
TRAL POSITION SIGNAL)
A/T onlyIgnition switch
ONSelector lever in “P” or “N”
positionP/N Range
Selector lever in “R”, “D”,
“2” or “L” positionD Range
EGR VALVE At specified idle speed after warming up 0 %
∆FUEL TANK LEVEL–0 – 100 %
BAROMETRIC PRESS–Display the barometric pres-
sure
FUEL PUMPWithin 3 seconds after ignition switch ON or
engine runningON
Engine stop at ignition switch ON. OFF SCAN TOOL DATA CONDITION REFERENCE VALUES
Downloaded from www.Manualslib.com manuals search engine 6-32 ENGINE GENERAL INFORMATION AND DIAGNOSIS
FUEL TANK LEVEL (%)
This parameter indicates approximate fuel level in the fuel tank. As the detectable range of the fuel level sensor
is set as 0 to 100%, however, with some models whose fuel tank capacity is smaller, the indicated fuel level may
be only 70% even when the fuel tank is full.
PNP SIGNAL (PARK / NEUTRAL POSITION SIGNAL, P/N RANGE or D RANGE)
It is detected by signal from TCM.
D range : A/T is in “R”, “D”, “2” or “L” range.
P/N range : A/T is in “P” or “N” range or the above signal is not inputted from TCM.
EGR VALVE (%)
This parameter indicates opening rate of EGR valve which controls the amount of EGR flow.
PSP SW
The Power Steering Pressure switch parameter displays ON when steering wheel is turned all the way to the
right or left.
Downloaded from www.Manualslib.com manuals search engine 6-34 ENGINE GENERAL INFORMATION AND DIAGNOSIS
ECM TERMINAL VOLTAGE VALUES TABLE
For TYPE A (See NOTE)
NOTE:
Type A is other than follows.
Type B is left hand steering vehicle equipped with fasten seat belt light and EGR valve or right hand
steering vehicle equipped with fasten seat belt light and immobilizer control system.
TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION
E191Ground––
2Ground––
3Ground––
4 EVAP canister purge valve 10 – 14 V Ignition switch ON
5Power steering pressure switch
(if equipped)0 – 1.3 VWhile engine running at idle speed, turn
steering wheel to right or left as far as it
stops
10 – 14 V Ignition switch ON
6 Idle air control valve 0 – 13 VAt specified idle speed after engine
warmed up
7 Heater of HO2S-1 10 – 14 V Ignition switch ON
8 Fuel injector NO.4 10 – 14 V Ignition switch ON
9 Fuel injector NO.1 10 – 14 V Ignition switch ON
10 Sensor ground––
11 Camshaft position sensor0 – 0.8 V and
4 – 6 VIgnition switch ON
12–– –
13Heater oxygen sensor-1 Refer to DTC P0130 diag. flow table
CO adjusting resistor (w/o HO2S) 0 – 5 V Ignition switch ON position
14
Engine coolant temp. sensor 0.55 - 0.95 VIgnition switch ON
Engine coolant temp. : 80 °C (176 °F)
15
Intake air temp. sensor 2.0 – 2.7 VIgnition switch ON
Intake air temp. : 20 °C (68 °F)
16 Throttle opening signal0.2 – 1.0 VIgnition switch ON position and throttle
valve at idle position
2.8 – 4.8 VIgnition switch ON position and throttle
valve fully open
17EGR valve (stepper motor coil 3, if
equipped)10 – 14 VIgnition switch ON position leaving engine
OFF
18EGR valve (stepper motor coil 1, if
equipped)10 – 14 VIgnition switch ON position leaving engine
OFF
19 Ignition coil #2––
20 Ignition coil #1––
21 Fuel injector NO.2 10 – 14 V Ignition switch ON
22 Power source for sensors 4.75 – 5.25 V Ignition switch ON
23 Crankshaft position sensor0 – 0.8 or
4 – 5 VIgnition switch ON position
24–– –
25 Knock sensor About 2.5 VAt specified idle speed after engine
warmed up