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 6-18 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC NO. DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
P0702 Transmission Control System Electrical
Refer to Section 7B.
These DTCs can not be read on vehicle without
Immobilizer indicator lamp (by ECM application of
SUZUKI scan tool). P0705 Temperature Sensor Circuit Malfunction
P0710Transmission Temperature Sensor Circuit Mal-
function
P0715Input / Turbine Speed Sensor Circuit Malfunc-
tion
P0720Output Shaft Speed Sensor Circuit Malfunc-
tion
P0725 Engine Speed Input Circuit Malfunction
P0730 Incorrect Gear Ratio
P0743 Torque Converter Clutch Circuit Electrical
P0753 Shift Solenoid A Electrical
P0758 Shift Solenoid B Electrical
P0763 Shift Solenoid C Electrical
P0768 Shift Solenoid D Electrical
P1700 Throttle Position Signal Input Malfunction
P1702Internal Control Module Memory Check Some
Error
P1709Engine Coolant Temperature Signal Input
Malfunction
P1887 Transfer Signal
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)Faulty in ECM
P1623
(No.81)ECU code not matched
NOTE:
For ( ) marked No. in DTC column, it is used for vehicle without Immobilizer indicator lamp.
DTC No.12 appears when none of the other codes is identified (vehicle without Immobilizer indica-
tor lamp).
Downloaded from www.Manualslib.com manuals search engine 6-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Visual inspection
Visually check following parts and systems.
INSPECTION ITEM REFERRING SECTION
Engine oil – level, leakage Section 0B
Engine coolant – level, leakage Section 0B
Fuel – level, leakage Section 0B
A/T fluid – level, leakage Section 0B
Air cleaner element – dirt, clogging Section 0B
Battery – fluid level, corrosion of terminal
Water pump belt – tension, damage Section 0B
Throttle cable – play, installation
Section 6E Vacuum hoses of air intake system – disconnection, looseness,
deterioration, bend
Connectors of electric wire harness – disconnection, friction
Fuses – burning Section 8
Parts – installation, bolt – looseness
Parts – deformation
Other parts that can be checked visually
Also check following items at engine start, if possible
Malfunction indicator lamp – operation Section 6
Charge warning lamp – operation Section 6H
Engine oil pressure warning lamp – operation Section 8 (Section 6 for pressure check)
Engine coolant temp. meter – operation Section 8
Fuel level meter – operation Section 8
Tachometer, if equipped – operation
Abnormal air being inhaled from air intake system
Exhaust system – leakage of exhaust gas, noise
Other parts that can be checked visually
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-21
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.
Downloaded from www.Manualslib.com manuals search engine 6-28 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Scan Tool Data
As the data values given below are standard values estimated on the basis of values obtained from the normally
operating vehicles by using a scan tool, use them as reference values. Even when the vehicle is in good condi-
tion, there may be cases where the checked value does not fall within each specified data range. Therefore,
judgment as abnormal should not be made by checking with these data alone.
Also, conditions in the below table that can be checked by the scan tool are those detected by ECM and output
from ECM as commands and there may be cases where the engine or actuator is not operating (in the condi-
tion) as indicated by the scan tool. Be sure to use the timing light to check the ignition timing.
NOTE:
With the generic scan tool, only star (
✱
✱✱ ✱) marked data in the table below can be read.
The triangle (
∆
∆∆ ∆) marked data in the table below can not be read for vehicle without immobilizer indi-
cator lamp at combination meter.
When checking the data with the engine running at idle or racing, be sure to shift M/T gear to the
neutral gear position and A/T gear to the “Park” position and pull the parking brake fully. Also, if
nothing or “no load” is indicated, turn OFF A/C, all electric loads, P/S and all the other necessary
switches.
SCAN TOOL DATA CONDITION REFERENCE VALUES
✱
✱✱ ✱FUEL SYSTEM B1 (FUEL
SYSTEM STATUS)At specified idle speed after warming up CLOSED (closed loop)
✱
✱✱ ✱
CALC LOAD
(CALCULATED LOAD
VALUE)At specified idle speed with no load after
warming up3 – 9 %
At 2500 r/min with no load after warming up 12 – 17 %
✱
✱✱ ✱COOLANT TEMP.
(ENGINE COOLANT
TEMP.)At specified idle speed after warming up 80 – 100 °C, 176 – 212 °F
✱
✱✱ ✱SHORT FT B1 (SHORT
TERM FUEL TRIM)At specified idle speed after warming up– 20 – +20 %
✱
✱✱ ✱LONG FT B1 (LONG TERM
FUEL TRIM)At specified idle speed after warming up– 15 – +15 %
✱
✱✱ ✱MAP (INTAKE MANIFOLD
ABSOLUTE PRESSURE)At specified idle speed with no load after30 – 37 kPa,
220 – 340 mmHg
✱
✱✱ ✱
ENGINE SPEED At idling with no load after warming upDesired idle speed
±50 r/min
✱
✱✱ ✱VEHICLE SPEED At stop 0 km/h, 0 MPH
✱
✱✱ ✱IGNITION ADVANCE
(IGNITION TIMING
ADVANCE FOR NO.1 CYL-
INDER)At specified idle speed with no load after
warming up5 – 16° BTDC
✱
✱✱ ✱
INTAKE AIR TEMP. At specified idle speed after warming upAmbient temp. :
+15 °C (59 °F)
–5 °C (23 °F)
✱
✱✱ ✱MAF (MASS AIR FLOW
RATE)At specified idle speed with no load after
warming up1 – 4 gm/sec
✱
✱✱ ✱
THROTTLE POS
(THROTTLE POSITION)Ignition switch
ON / engine
stoppedThrottle valve fully closed 7 – 18 %
Throttle valve fully open 70 – 90 %
✱
✱✱ ✱O2S B1 S1 (HEATED OXY-
GEN SENSOR-1)At specified idle speed after warming up 0.01 – 0.95 V
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 ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-31
THROTTLE POS (ABSOLUTE THROTTLE POSITION, %)
When throttle position sensor is fully closed position, throttle opening is indicated as 0% and 100% full open
position.
OXYGEN SENSOR B1 S1 (HEATED OXYGEN SENSOR-1, V)
It indicates output voltage of HO2S-1 installed on exhaust manifold (pre-catalyst).
OXYGEN SENSOR B1 S2 (HEATED OXYGEN SENSOR-2, V)
It indicates output voltage of HO2S-2 installed on exhaust pipe (post-catalyst). It is used to detect catalyst dete-
rioration.
DESIRED IDLE (DESIRED IDLE SPEED, rpm)
The Desired Idle Speed is an ECM internal parameter which indicates the ECM requested idle. If the engine is
not running, this number is not valid.
TP SENSOR VOLT (THROTTLE POSITION SENSOR OUTPUT VOLTAGE, V)
The Throttle Position Sensor reading provides throttle valve opening information in the form of voltage.
INJ PULSE WIDTH (FUEL INJECTION PULSE WIDTH, msec.)
This parameter indicates time of the injector drive (valve opening) pulse which is output from ECM (but injector
drive time of NO.1 cylinder for multiport fuel injection).
IAC FLOW DUTY (IDLE AIR (SPEED) CONTROL DUTY, %)
This parameter indicates current flow time rate within a certain set cycle of IAC valve (valve opening rate) which
controls the amount of bypass air (idle speed).
TOTAL FUEL TRIM (%)
The value of Total Fuel Trim is obtained by putting values of short Term Fuel Trim and Long Term Fuel Trim
together. This value indicates how much correction is necessary to keep the air / fuel mixture stoichiometrical.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage inputted from main relay to ECM.
CANIST PURGE DUTY (EVAP CANISTER PURGE FLOW DUTY, %)
This parameter indicates valve ON (valve open) time rate within a certain set cycle of EVAP purge solenoid
valve which controls the amount of EVAP purge.
0% means that the purge valve is completely closed while 100% is a fully open valve.
CLOSED THROTTLE POSITION (ON / OFF)
This parameter will read ON when throttle valve is fully closed, or OFF when the throttle is not fully closed.
FUEL CUT (ON / OFF)
ON : Fuel being cut (output signal to injector is stopped)
OFF : Fuel not being cut
A/C CONDENSER FAN (A/C CONDENSER FAN RELAY, ON / OFF)
ON : Command for condenser fan relay operation being output.
OFF : Command for relay operation not being output.
ELECTRIC LOAD (ON / OFF)
ON : Headlight, small light, heater fan or rear window defogger ON signal inputted.
OFF : Above electric loads all turned OFF.
A/C SWITCH (ON / OFF)
ON : Command for A/C operation being output from ECM to A/C amplifier.
OFF : Command for A/C operation not being output.
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-119
Table B-6 Electric Load Signal Circuit Check
INSPECTION
1. Rear defogger switch 3. Blower fan switch [B] : Case of TYPE B is shown (See NOTE)
2. Light switch [A] : Case of TYPE A is shown (See NOTE)
NOTE:
For TYPE A and TYPE B, refer to the NOTE in “ECM Terminal Voltage Values Table” for applicable
model.
Step Action Yes No
1 Is SUZUKI scan tool available? Go to Step 2. Go to Step 3.
2 Check Electric Load Signal Circuit.
1) Connect SUZUKI scan tool to DLC with igni-
tion switch OFF. See Fig.1.
2) Start engine and select “DATA LIST” mode
on scan tool.
3) Check electric load signal under following
each condition. See Table 1.
Is check result satisfactory?Electric load signal circuit
is in good condition.“R/W”, “R/Y” and/or “Bl/Y”
circuit open or short, Elec-
tric load diodes malfunc-
tion or Each electric load
circuit malfunction.
3 Check Electric Load Signal Circuit.
1) Turn ignition switch ON.
2) Check voltage at each terminals E17-16,
E18-17 and E18-24 (Case of TYPE A) or
E18-12, E18-17 and E17-13 (Case of TYPE
B) (See NOTE) of ECM connector con-
nected, under above each condition. See
Fig. 2. and Table 1.
Is each voltage as specified?Electric load signal circuit
is in good condition.“R/W”, “R/Y” and/or “Bl/Y”
circuit open or short, Elec-
tric load diodes malfunc-
tion or Each electric load
circuit malfunction.