ECM SUZUKI GRAND VITARA 2001 2.G Owner's Manual

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

6-1-22 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
For immobilizer control system (Refer to Section 8G for diagnosis)
P0753
(No.61)
(No.62)Shift solenoid A (#1) electricalMonitor signal OFF is detected when
shift solenoid A (#1) is ON or monitor
signal ON is detected when it is OFF.1 driving
cycleNot
applicable
P0756Shift solenoid B (#2) 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
P0758
(No.63)
(No.64)Shift solenoid B (#2) electricalMonitor signal OFF is detected when
shift solenoid B (#2) is ON or monitor
signal ON is detected when it is OFF.1 driving
cycleNot
applicable
P18754WD low switch circuit mal-
functionDifference between vehicle speed
detected by VSS and vehicle speed
detected by output speed sensor and
compensated by 4WD low switch is
larger than specification.2 driving
cyclesNot
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)
P1620
(No.84)ECU code not registered
Refer to Section 8G P1621
(No.83)NO ECU code transmitted
from Immobilizer Control Mod-
ule
P1622
(No.82)Fault ECM
P1623
(No.81)ECU code not matched
NOTE:
DTC NO. with (*) is detected only vehicle without monitor connector.
DTC No. with (**) is detected only vehicle with monitor connector.
For ( ) marked No. in DTC column, it is used for vehicle with monitor connector.
DTC No.12 appears when none of the other codes is identified.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-23
Fail-Safe Table
When any of the following DTCs is detected, ECM (PCM) enters fail-safe mode as long as malfunction continues
to exist but that mode is canceled when ECM (PCM) detects normal condition after that.
DTC NO. TROUBLE AREA FAIL SAFE OPERATION
P0100
(No.33, 34)MAF SENSOR• Injector drive time (fuel injection volume) is determined according to
throttle valve opening and engine speed.
• EGR valve stops.
• Air flow of IAC valve is limited.
P0110
(No.23, 25)IAT SENSOR Each control is performed on the basis of 22.1°C intake air temp.
P0115
(No.14, 15)ECT SENSOR• Each control except 4-A/T is performed on the basis of 29.9°C engine
coolant temp.
• 4-A/T control is performed assuming 31°C (engine warmed up) or
higher after 15 min. from engine start.
P0120
(No.21, 22)TP SENSOR• Each control except 4-A/T is performed on the basis of 124.5° throttle
valve opening.
• 4-A/T control is performed on the basis of 0° throttle valve opening.
P0460 FUEL LEVEL SENSOR Each control is performed in the basis of full fuel level.
P0500VEHICLE SPEED
SENSORAir flow of IAC valve is limited.
P1450BAROMETRIC
PRESSURE SENSOREach control is performed based on 760 mmHg barometric pressure.
P0705 TR SWITCH A/T control is performed in priority order of L, 2, N, D, R and P.
P0720OUTPUT SPEED
SENSOR CIRCUIT
MALFUNCTIONA/T control is performed by using signal from VSS.
P0753SHIFT SOLENOID
A (#1)• A/T control using 3rd gear is performed when D range, 1st, or 2nd
gear is used.
• TCC solenoid OFF
P0758SHIFT SOLENOID
B (#2)• A/T control using 4th gear is performed when D range, 2nd or 3rd
gear is used.
• When both shift solenoids A (#1) and B (#2) failed simultaneously,
A/T control using 4th gear is always performed in D range.
• TCC solenoid OFF
P0743TCC (Lock-up)
SOLENOIDTCC (Lock-up) solenoid OFF

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.

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

6-1-34 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Poor gasoline mileage
Faulty spark plug (improper gap, heavy depos-
its, and burned electrodes, etc.)Spark plugs in Section 6F2.
Fuel pressure out of specification “DIAG. FLOW TABLE B-3” in this
section.
Faulty TP sensor, ECT sensor or MAF sensor TP sensor, ECT sensor or MAF
sensor in Section 6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty injector Fuel injector 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.
Poor valve seating Valves inspection in Section 6A2.
Dragging brakes Diagnosis in Section 5.
Slipping clutch Diagnosis in Section 7C1.
Thermostat out of order Thermostat in Section 6B.
Improper tire pressure Diagnosis in Section 3.
Excessive engine oil
consumptionSticky piston ring Piston cleaning in Section 6A2.
Worn piston and cylinder Cylinders, pistons and piston rings
inspection in Section 6A2.
Worn piston ring groove and ring Pistons and piston rings inspection
in Section 6A2.
Improper location of piston ring gap Pistons installation in Section 6A2.
Worn or damaged valve stem seal Valves and cylinder head in Sec-
tion 6A2.
Worn valve stem Valves inspection in Section 6A2.
Low oil pressure
Improper oil viscosity Engine oil and oil filter change in
Section 0B.
Malfunctioning oil pressure switch Oil pressure switch inspection in
Section 8.
Clogged oil strainer Oil pan and oil pump strainer clean-
ing in Section 6A2.
Functional deterioration of oil pump Oil pump in Section 6A2.
Worn oil pump relief valve Oil pump in Section 6A2.
Excessive clearance in various sliding parts “INSPECTION” for each parts in
Section 6A2. Condition Possible Cause Correction

6-1-36 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Inspection of PCM (ECM) and its Circuits
PCM (ECM) and its circuits can be checked at PCM (ECM) wiring
couplers by measuring voltage and resistance.
VOLTAGE CHECK
1) Remove PCM (ECM) cover from bracket referring to PCM
(ECM) REMOVAL.
2) Check voltage at each terminal of couplers connected.CAUTION:
PCM/ECM cannot be checked by itself. It is strictly pro-
hibited to connect voltmeter or ohmmeter to PCM (ECM)
with couplers disconnected from it.
NOTE:
As each terminal voltage is affected by the battery volt-
age, confirm that it is 11 V or more when ignition switch
is ON.
1. PCM (ECM)
2. PCM (ECM) connector (Viewed from harness side)