ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-15
STEP 9. TROUBLESHOOTING FOR DTC
Based on the DTC indicated in Step 6 or 7 and referring to the applicable DTC diag. flow table in this section,
locate the cause of the trouble, namely in a sensor, switch, wire harness, connector, actuator, ECM (PCM) or
other part and repair or replace faulty parts.
STEP 10. CHECK FOR INTERMITTENT PROBLEM
Check parts where an intermittent trouble is easy to occur (e.g., wire harness, connector, etc.), referring to
“INTERMITTENT AND POOR CONNECTION” in Section 0A and related circuit of DTC recorded in step 2.
STEP 11. FINAL CONFIRMATION TEST
Confirm that the problem symptom has gone and the engine is free from any abnormal conditions. If what has
been repaired is related to the DTC, clear the DTC once, perform DTC confirmation procedure and confirm that
no malfunction DTC (a normal code) is indicated.
6-1-16 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Malfunction Indicator Lamp (MIL) Check
1) Turn ON ignition switch (but the engine at stop) and check
that MIL (1) lights.
If MIL does not light up, go to “Diagnostic Flow Table A-1” for
troubleshooting.
2) Start engine and check that MIL turns OFF.
3) If MIL remains ON, and no DTC is stored in ECM (PCM), go
to “Diagnostic Flow Table A-2” for troubleshooting.
Diagnostic Trouble Code (DTC) Check
[Using SUZUKI scan tool]
1) Prepare generic scan tool or SUZUKI scan tool (2).
2) With ignition switch OFF, connect it to data link connector
(DLC) (3) located on underside of instrument panel at
driver’s seat side.
Special tool
(A) : SUZUKI scan tool
3) Turn ignition switch ON and confirm that MIL lights.
4) Read DTC and freeze frame data according to instructions
displayed on scan tool and print them or write them down.
Refer to scan tool operator’s manual for further details.
If communication between scan tool and ECM (PCM) is not
possible, check if scan tool is communicable by connecting it
to ECM (PCM) in another vehicle. If communication is possi-
ble 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.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-17
[Without Using SUZUKI Scan Tool] (Vehicle with Monitor
Connector)
1) Check malfunction indicator lamp referring to “Malfunction
Indicator Lamp Check” in this section.
2) With the ignition switch OFF position, disconnect SUZUKI
scan tool if connected and using service wire (4), connect
diagnosis switch terminal (1) to ground terminal (2) in moni-
tor connector (3).
3) With the ignition switch ON position and leaving engine OFF,
read DTC from flashing pattern of malfunction indicator
lamp. Refer to “Diagnostic Trouble Code Table”.
If lamp remains ON, go to “Diagnostic Flow Table A-4”.
4) After completing the check, turn the ignition switch OFF posi-
tion and disconnect service wire from monitor coupler.
Diagnostic Trouble Code (DTC) Clearance
[Using scan tool]
1) With ignition switch OFF, connect generic scan tool or
SUZUKI scan tool to data link connector (DLC).
2) Turn ignition switch ON.
3) Erase DTC according to instructions displayed on scan tool.
Freeze frame data is cleared with the DTC. Refer to scan tool
operator’s manual for further details.
4) After completing the clearance, turn ignition switch off and
disconnect scan tool from data link connector. NOTE:
If abnormality or malfunction lies in two or more areas,
malfunction indicator lamp indicates applicable codes
three times each.
And flashing of these codes is repeated as long as
diagnosis terminal is grounded and ignition switch is
held at ON position.
Take a note of diagnostic trouble code indicated first.
NOTE:
DTC and freeze frame data stored in ECM (PCM) memory
are also cleared in following cases. Be careful not to
clear them before keeping their record.
When power to ECM (PCM) is cut off (by disconnecting
battery cable, removing fuse or disconnecting ECM
(PCM) connectors)
When the same malfunction (DTC) is not detected
again during 40 engine warm-up cycles (refer to
“WARM-UP CYCLE” of “ON-BOARD DIAGNOSTIC SYS-
TEM” in this section) (Vehicle without monitor connec-
tor)
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-21
For A/T system (Refer to Section 7B1 for diagnosis)
P0505Idle air control system mal-
functionDifference between desired idle speed
and actual idle speed continues to
exceed specified value for longer than
specified time.2 driving
cyclesNot
applicable
P0601
(No.71)Internal control module mem-
ory check sum errorData write error (or check sum error)
when written into ECM1 driving
cycle1 driving
cycle
P1408Manifold absolute pressure
sensor circuit malfunctionManifold absolute pressure sensor
output voltage is higher or lower than
specified value (or sensor circuit
shorted to ground or open).2 driving
cyclesNot
applicable
P1450Barometric pressure sensor
circuit malfunctionBarometric pressure is lower or higher
than specification.1 driving
cycleNot
applicable
P1451Barometric pressure sensor
performance problemDifference between intake manifold
pressure and barometric pressure is
larger than specification.2 driving
cyclesNot
applicable
P1500Engine starter signal circuit
malfunctionEngine starts with no starter signal or
signal input during long period after
start.2 driving
cyclesNot
applicable
P1510ECM back-up power supply
malfunctionNo back-up power after starting
engine.1 driving
cycleNot
applicable DTC NO. DETECTED ITEMDETECTING CONDITION
(DTC will set when detecting : )MIL
(vehicle
without
monitor
connector)MIL
(vehicle
with
monitor
connector)
DTC NO. DETECTED ITEMDETECTING CONDITION
(DTC will set when detecting : )MIL
(vehicle
without
monitor
connector)MIL
(vehicle
with
monitor
connector)
P0705
(No.72)Transmission range switch cir-
cuit malfunctionMultiple signals inputted simulta-
neously or P, R, N, D, 2 or L range sig-
nal not inputted while running at
60km/h or more.2 driving
cyclesNot
applicable
P0715
(No.76)Input speed sensor circuit
malfunctionInput speed sensor signal is lower
than specification while running.2 driving
cyclesNot
applicable
P0720
(No.75)Output speed sensor circuit
malfunctionOutput speed sensor signal not input-
ted while VSS signal being inputted.2 driving
cyclesNot
applicable
P0741TCC (lock-up) solenoid perfor-
mance or stuck offActual TCC operation does not agree
with ON/OFF control from PCM to
TCC.2 driving
cyclesNot
applicable
P0743
(No.65)
(No.66)TCC (lock-up) solenoid electri-
calMonitor signal OFF is detected when
TCC control solenoid is ON or monitor
signal ON is detected when it is OFF.1 driving
cycleNot
applicable
P0751Shift solenoid A (#1) perfor-
mance or stuck offGear change control from PCM to A/T
does not agree with actual gear posi-
tion of A/T.2 driving
cyclesNot
applicable
6-1-24 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
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 output from ECM (PCM) as
Commands and there may be cases where the engine or actuator is not operating (in the condition) as indicated
by the scan tool. Be sure to use the timing light to check the ignition timing referring to Section 6F2.
NOTE:
For asterisk (
✱) marked item in “OTHER” column, item can be read only SUZUKI scan tool.
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 CONDITIONNORMAL CONDITION/
REFERENCE VALUEOTHER
COOLANT TEMP.
(Engine Coolant Temp.)At specified idle speed after warming up 80 – 100 °C
(176 – 212 °F)
INTAKE AIR TEMP. At specified idle speed after warming up Environmental temp.
+20 °C (+36 °F)
–5 °C (–9 °F)
DESIRE IDLE
(Desired idle speed)At idling with no load after warming up
700 rpm✱
CLOSED THROT POS
(Closed Throttle Position)With ignition switch ON, accelerator pedal
releasedON
✱
With ignition switch ON, accelerator pedal
depressedOFF
IAC FLOW DUTY At specified idle speed after warming up 5 – 40 %✱
ENGINE SPEED At idling with no load after warming up Desired idle speed
± 50 rpm
SHORT FT B1
(Short term fuel trim)At specified idle speed after warming up
–15 ~ +15 %
SHORT FT B2
(Short term fuel trim)At specified idle speed after warming up
–15 ~ +15 %
LONG FT B1
(Long term fuel trim)At specified idle speed after warming up
–15 ~ +15 %
LONG FT B2
(Long term full trim)At specified idle speed after warning up
–15 ~ +15 %
IGNITION ADVANCE At specified idle speed with no load after
warming up6 – 17°
BATTERY VOLTAGE Ignition switch ON/engine stopped 10 – 14 V✱
MAF (Mass Air Flow
Rate)At specified idle speed with no load after
warming up.2.6 – 4.5 g/s
0.34 – 0.59 lb/min
At 2500 r/min with no load after warming up. 10 – 16 g/s
1.32 – 2.11 lb/min
INJ PULSE WIDTH B1
(Fuel Injection Pulse
Width)At specified idle speed with no load after
warming up.2.0 – 3.3 msec
✱
At 2500 r/min with no load after warming up. 2.2 – 3.2 msec
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-27
Scan tool data definitions
COOLANT TEMP (Engine Coolant Temp., °C/°F)
It is detected by engine coolant temp. sensor.
INTAKE AIR TEMP (°C/°F)
It is detected by intake air temp. sensor.
DESIRE IDLE (Desired Idle Speed RPM)
The desired idle speed is an ECM (PCM) internal parameter which indicates the ECM (PCM) requested idle. If
the engine is not running, the number is not valid.
CLOSED THROT POS (Closed Throttle Position ON/OFF)
This parameter will read ON when the throttle valve is fully closed. Or OFF when the throttle is not fully closed.
IAC FLOW DUTY (%)
This parameter indicates IAC valve opening rate which controls bypass air flow.
ENGINE SPEED (RPM)
It is computed by reference pulses from the Camshaft Position Sensor.
SHORT FT B1 (Short Term Fuel Trim Bank 1, %) / SHORT FT B2 (Short Term Fuel Trim Bank 2, %)
Short term fuel trim value represents short 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.
LONG FT B1 (Long Term Fuel Trim Bank 1, %) / LONG FT B2 (Long Term Fuel Trim Bank 2, %)
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.
IGNITION ADVANCE (Ignition Timing Advance For No.1 Cylinder, °)
Ignition timing of No.1 cylinder is commanded by ECM (PCM). The actual ignition timing should be checked by
using the timing light.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage inputted from main relay to ECM (PCM).
MAF (Mass Air Flow Rate, g/s, lb/min)
It represents total mass of air entering intake manifold which is measured by mass air flow sensor.
INJ PULSE WIDTH B1 (Fuel Injection Pulse Width Bank 1, msec) / INJ PULSE WIDTH B2 (Fuel Injec-
tion Pulse Width Bank 2, msec)
This parameter indicates time of the injector drive (valve opening) pulse which is output from ECM (PCM).
THROTTLE POS (Absolute Throttle Position, %)
When throttle position sensor is fully closed position, throttle opening is indicated as 0 % and 100 % for full open
position.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-31
Engine Diagnosis Table
Perform troubleshooting referring to following table when ECM (PCM) has detected no DTC and no abnormality
has been found in visual inspection and engine basic inspection previously.
Condition Possible Cause Correction
Hard starting
(Engine cranks OK)Faulty idle air control system “DIAG. FLOW TABLE B-4” in this
section.
Faulty ECT sensor or MAF sensor ECT sensor or MAF sensor in Sec-
tion 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Low compression Compression check in Section
6A2.
Faulty hydraulic valve lash adjuster Valve lash adjuster in Section 6A2.
Compression leak from valve seat Valves inspection in Section 6A2.
Sticky valve stem Valves inspection in Section 6A2.
Weak or damaged valve springs Valves spring inspection in Section
6A2.
Compression leak at cylinder head gasket Cylinder head inspection in Section
6A2.
Sticking or damaged piston ring Piston ring inspection in Section
6A2.
Worn piston, ring or cylinder Cylinders, pistons and piston rings
inspection in Section 6A2.
Malfunctioning PCV valve PCV system inspection in Section
6E2.
Engine has no power
Engine overheating Refer to “OVERHEATING” in this
table.
Defective spark plug Spark plugs in Section 6F2.
Faulty ignition coil with ignitor Ignition coil in Section 6F2.
Fuel pressure out of specification
(dirty fuel filter, dirty or clogged fuel hose or
pipe, malfunctioning fuel pressure regulator,
malfunctioning fuel pump)“DIAG. FLOW TABLE B-3” in this
section.
Maladjusted TP sensor installation angle TP sensor in Section 6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty injector Fuel injector in Section 6E2.
Faulty TP sensor, ECT sensor or MAF sensor TP sensor, ECT sensor or MAF
sensor in Section 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Low compression Refer to the same item in “HARD
STARTING” of this table.
Dragging brakes Diagnosis in Section 5.
Slipping clutch Diagnosis in Section 7C1.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-33
Surges
(Engine power varia-
tion under steady
throttle or cruise.
Feels like the vehicle
speeds up and down
with no change in the
accelerator pedal.)Defective spark plug
(excess carbon deposits, improper gap, and
burned electrodes, etc.)Spark plugs in Section 6F2.
Variable fuel pressure
(clogged fuel filter, kinky or damaged fuel hose
and line, faulty fuel pressure regulator)“DIAG. FLOW TABLE B-3” in this
section.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty MAF sensor MAF sensor in Section 6E2.
Faulty injector Fuel injector in Section 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Excessive detonation
(The engine makes
sharp metallic knocks
that change with throt-
tle opening. Sounds
like pop corn pop-
ping.)Engine overheating Refer to “OVERHEATING” in this
table.
Faulty spark plug Spark plugs in Section 6F2.
Improper ignition timing Ignition timing in Section 6F2.
Clogged fuel filter and fuel lines Fuel pressure check in Section
6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty ECT sensor or MAF sensor ECT sensor or MAF sensor in Sec-
tion 6E2.
Faulty injector Fuel injector in Section 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Excessive carbon deposits in combustion
chamberPiston and cylinder head cleaning
in Section 6A2.
Poor knock sensor performance “DTC P0325 DIAG. FLOW TABLE”
in this section.
Overheating
Inoperative thermostat Thermostat in Section 6B.
Poor water pump performance Water pump in Section 6B.
Clogged or leaky radiator Radiator in Section 6B.
Improper engine oil grade Engine oil and oil filter change in
Section 0B.
Clogged oil filter or oil strainer Oil pressure check in Section 6A2.
Poor oil pump performance Oil pressure check in Section 6A2.
Dragging brakes Diagnosis in Section 5.
Slipping clutch Diagnosis in Section 7C1.
Blown cylinder head gasket Cylinder head inspection in Section
6A2. Condition Possible Cause Correction