6-1-18 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
[Without using scan tool]
1) Turn the ignition switch OFF position.
2) Disconnect battery negative cable for specified time below to
erase diagnostic trouble code stored in ECM memory and
reconnect it.
Time required to erase DTC:
Diagnostic Trouble Code (DTC) Table
Ambient
temperatureTime to cut power to ECM
Over 0°C (32°F) 30 sec. or longer
Under 0°C
(32°F)Not specifiable.
Select a place with higher than 0°C
(32°F) temperature.
DTC NO. DETECTED ITEMDETECTING CONDITION
(DTC will set when detecting : )MIL
(vehicle
without
monitor
connector)MIL
(vehicle
with
monitor
connector)
P0100
(No.34)
Mass air flow circuit malfunc-
tionSensor output too low
1 driving
cycle1 driving
cycle
P0100
(No.33)Sensor output too high
P0110
(No.25)
Intake air temp. circuit mal-
functionIntake air temp. circuit low input
1 driving
cycle1 driving
cycle
P0110
(No.23)Intake air temp. circuit high input
P0115
(No.15)
Engine coolant temp. circuit
malfunctionEngine coolant temp. circuit low input
1 driving
cycle1 driving
cycle
P0115
(No.14)Engine coolant temp. circuit high input
P0120
(No.22)
Throttle position circuit mal-
functionThrottle position circuit low input
1 driving
cycle1 driving
cycle
P0120
(No.21)Throttle position circuit high input
P0121Throttle position circuit perfor-
mance problemPoor performance of TP sensor2 driving
cyclesNot
applicable
*P0130HO2S circuit malfunction
(Bank 1 - Sensor 1)Min. output voltage of HO2S-1 is
higher than specification.
2 driving
cyclesNot
applicable Min. output voltage of HO2S-1 is
lower than specification.
Output voltage of HO2S-1 fails to go
above specification.
**P0130
(No.13)HO2S (Bank 1 - Sensor 1) no
activity detectedOutput voltage of HO2S-1 fails to go
above specification (or HO2S-1 cir-
cuit open).2 driving
cycles2 driving
cycles
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) 6-1-25
INJ PULSE WIDTH B2 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
THROTTLE POS
(Absolute Throttle Posi-
tion)With ignition switch ON/warmed up engine
stopped, accelerator pedal released9.8 – 18.2 %
With ignition switch ON/warmed up engine
stopped, accelerator pedal depressed fully72 – 87.2 %
TP SENSOR VOLT
(TP Sensor Output Volt-
age)With ignition switch ON/warmed up engine
stopped, accelerator pedal released0.49 – 0.91 V
✱
With ignition switch ON/warmed up engine
stopped, accelerator pedal depressed fully.3.76 – 4.36 V
O2S B1 S1
(HO2S-1 Output Voltage)At specified idle speed after warming up
0.05 – 0.95 V
O2S B1 S2
(HO2S-2 Output Voltage)When engine is running at 2000 r/min. for 3
min or longer after warming up.0.05 – 0.95 V
O2S B2 S1
(HO2S-2 Output Voltage)When engine is running at 2000 r/min. for 3
min or longer after warming up.0.05 – 0.95 V
O2S B2 S2
(HO2S-2 Output Voltage)When engine is running at 2000 r/min. for 3
min or longer after warming up.0.05 – 0.95 V
FUEL SYSTEM B1
(Fuel System Status)At specified idle speed after warming up.
Closed✱
FUEL SYSTEM B2
(Fuel System Status)At specified idle speed after warming up.
Closed
CALC LOAD
(Calculated Load Value)At specified idle speed with no load after
warming up.10 – 25 %
At 2500 r/min with no load after warming up. 14 – 23 %
TOTAL FT TRIM B1 At specified idle speed after warming up. –30 – +30 %✱
TOTAL FT TRIM B2 At specified idle speed after warming up. –30 – +30 %
MAP At specified idle speed after warming up. 25 – 35 kPa
CANIST PRG DUTY
(EVAP Canister Purge
Flow Duty)At specified idle speed after warming up.
0 %✱
VEHICLE SPEED. At stop. 0 km/h 0 MPH
FUEL CUT When engine is at fuel cut condition ON
✱
Other than fuel cut condition OFF
EGR VALVE At specified idle speed after warming up 0 %✱
BLOWER FAN Ignition switch ON, blower fan switch ON ON
✱
Ignition switch ON, blower fan switch OFF OFF
A/C CONDENSER FAN Ignition switch ON, A/C not operating OFF
✱
Ignition switch ON, A/C operating ON
PSP SWITCH Engine running at idle speed and steering
wheel at straight ahead positionOFF
✱
Engine running at idle speed and steering
wheel turned to the right or left as far as it
stopsON
A/C SWITCH
(if equipped)When A/C not operating OFF
✱
When A/C operating ON SCAN TOOL DATA CONDITIONNORMAL CONDITION/
REFERENCE VALUEOTHER
6-1-26 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
PNP SIGNAL (Transmis-
sion Range Switch) (for 4-
A/T)With ignition switch ON, selector lever in “P”
or “N” positionP/N Range
✱
With ignition switch ON, selector lever in “R”,
“D”, “2” or “L” positionD Range
FUEL TANK LEVEL Ignition switch ON 0 – 100 %✱
ELECTRIC LOAD Ignition ON, small light OFF OFF✱
Ignition switch ON, small light ON ON✱
VSS (Vehicle speed sen-
sor) (for 4-A/T)At stop.
0 km/h 0 MPH✱
GEAR POSITION (for 4-
A/T)Ignition switch ON, selector lever is shifted at
“R”, “D”, “2” or “L” range and vehicle stops.1st✱
THROT POS LEVEL
(Throttle position level for
4-A/T)“0” (about idle position), “1”,“2”,“3”,“4”,“5”,“6” or “7” (about full open)
appears according to throttle valve opening.✱
SHIFT SOL #1 (A)
CON (Shift solenoid #1
command signal)
MON (Shift solenoid #1
monitor) (for 4-A/T)Ignition switch ON
Selector lever is shifted at “P”, “R”, “N”, “D”,
“2” or “L” range.
Vehicle stops.ON✱
SHIFT SOL #2 (B)
CON (Shift solenoid #2
command signal)
MON (Shift solenoid #2
monitor) (for 4-A/T)Ignition switch ON
Selector lever is shifted at “P”, “R”, “N”, “D”,
“2” or “L” range.
Vehicle stops.OFF✱
TCC SOL (for 4-A/T)
CON (Torque converter
clutch solenoid command
signal)
MON (Torque converter
clutch solenoid monitor)Ignition switch ON
Selector lever is shifted at “P”, “R”, “N”, “D”,
“2” or “L” range.
Vehicle stops.OFF✱
TRANS RANGE
(for 4-A/T)Ignition switch ON, selector lever is at “P”,
“R”, “N”, “D”, “2” or “L” range.P, R, N, D, 2 or L✱
BRAKE SW
(Brake, stop lamp, switch)
(for 4-A/T)Ignition switch ON, Brake pedal is released. OFF
✱
Ignition switch ON, Brake pedal is
depressed.ON
O/D OFF SW
(Overdrive cut switch)Ignition switch ON, Overdrive cut switch OFF OFF
✱
Ignition switch ON, Overdrive cut switch ON ON
MODE SELECT SW
(Power/Normal change
switch) (for 4-A/T)Ignition switch ON, P/N change switch is at
normal position.NORMAL
✱
Ignition switch ON, P/N change switch is at
power position.POWER
4WD-L SW
(4WD low switch)Ignition switch ON, Transfer lever is shifted
at “4H” or “2H” position.OFF
✱
Ignition switch ON, Transfer lever is shifted
at “4L” position.ON SCAN TOOL DATA CONDITIONNORMAL CONDITION/
REFERENCE VALUEOTHER
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.
6-1-32 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Improper engine idling
or engine fails to idleFaulty spark plug Spark plugs in Section 6F2.
Faulty ignition coil with ignitor Ignition coil in Section 6F2.
Fuel pressure out of specification “DIAG. FLOW TABLE B-3” in this
section.
Engine overheating Refer to “OVERHEATING” in this
table.
Maladjusted TP sensor installation angle if
adjustableTP sensor in Section 6E2.
Faulty idle air control system “DIAG. FLOW TABLE B-4” in this
section.
Faulty FIA (fast idle air) valve FIA valve in Section 6E2.
Faulty evaporative emission control system EVAP control system in Section
6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty injector Fuel injection in Section 6E2.
Faulty ECT sensor, TP sensor or MAF sensor ECT sensor, TP 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.
Malfunctioning PCV valve PCV system inspection in Section
6E2.
Engine hesitates
(Momentary lack of
response as the accel-
erator is depressed.
Can occur at all vehi-
cle speeds.
Usually most severe
when first trying to
make the vehicle
move, as from a stop
sign.)Spark plug faulty or plug gap as out of adjust-
mentSpark plugs in Section 6F2.
Fuel pressure out of specification
(clogged fuel filter, faulty fuel pressure regula-
tor, clogged fuel filter, hose or pipe)“DIAG. FLOW TABLE B-3” in this
section.
Engine overheating Refer to “OVERHEATING” in this
table.
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. Condition Possible Cause Correction
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