ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-1
6-1
SECTION 6-1
ENGINE GENERAL INFORMATION AND
DIAGNOSIS (H27 ENGINE)
CONTENTS
General Information ...................................... 6-1-3
Statement of Cleanliness and Care ............ 6-1-3
General Information on Engine Service ...... 6-1-3
Precaution on Fuel System Service ............ 6-1-4
Fuel Pressure Relief Procedure .................. 6-1-5
Fuel Leakage Check Procedure .................. 6-1-5
Engine Diagnosis .......................................... 6-1-6
General Description .................................... 6-1-6
On-Board Diagnostic System (Vehicle
without Monitor Connector) ......................... 6-1-6
On-Board Diagnostic System (Vehicle with
Monitor Connector) ..................................... 6-1-9
Precaution in Diagnosing Trouble ............. 6-1-10
Engine Diagnostic Flow Table ................... 6-1-11
Malfunction Indicator Lamp (MIL) Check... 6-1-16
Diagnostic Trouble Code (DTC) Check ..... 6-1-16
Diagnostic Trouble Code (DTC) Clearance 6-1-17
Diagnostic Trouble Code (DTC) Table ...... 6-1-18For A/T system (Refer to Section 7B1
for diagnosis)......................................... 6-1-21
For immobilizer control system (Refer to
Section 8G for diagnosis) ...................... 6-1-22
Fail-Safe Table.......................................... 6-1-23
Scan Tool Data ......................................... 6-1-24
Scan tool data definitions ...................... 6-1-27
Engine Diagnosis Table ............................ 6-1-31
Inspection of PCM (ECM) and its Circuits. 6-1-36
Table A-1 Malfunction Indicator Lamp
Circuit Check – Lamp Does Not Come
“ON” or Dims at Ignition Switch ON
(But Engine at Stop).................................. 6-1-43
Table A-2 Malfunction Indicator Lamp
Circuit Check – Lamp Remains “ON” after
Engine Starts ............................................ 6-1-44
Table A-3 Malfunction Indicator Lamp
Check – MIL Flashes at Ignition Switch
ON (Vehicle with Monitor Connector) ....... 6-1-45 WARNING:
For vehicles equipped with Supplemental Restraint (Air Bag) System:
Service on and around the air bag system components or wiring must be performed only by an
authorized SUZUKI dealer. Refer to “Air Bag System Components and Wiring Location View” under
“General Description” in air bag system section in order to confirm whether you are performing ser-
vice on or near the air bag system components or wiring. Please observe all WARNINGS and “Ser-
vice Precautions” under “On-Vehicle Service” in air bag system section before performing service
on or around the air bag system components or wiring. Failure to follow WARNINGS could result in
unintentional activation of the system or could render the system inoperative. Either of these two
conditions may result in severe injury.
Technical service work must be started at least 90 seconds after the ignition switch is turned to the
“LOCK” position and the negative cable is disconnected from the battery. Otherwise, the system
may be activated by reserve energy in the Sensing and Diagnostic Module (SDM).
NOTE:
Whether following systems (parts) are used in the particular vehicle or not depends on specifications.
Be sure to bear this in mind when performing service work.
Monitor connector
CKP sensor
MAP sensor
EGR valve
Heated oxygen sensor or CO adjusting resistor
Three way catalytic converter, Warm-up three way catalytic converter
6-1-10 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DATA LINK CONNECTOR (DLC)
DLC (1) is in compliance with SAEJ1962 in its installation posi-
tion, the shape of connector and pin assignment.
K line of ISO 9141 is used for SUZUKI scan tool to communicate
with ECM (PCM), ABS control module and air bag SDM. SUZUKI
serial data line is used for SUZUKI scan tool to communicate with
Immobilizer control module.
Precaution in Diagnosing Trouble
• Don’t disconnect couplers from ECM (PCM), battery cable from battery, ECM (PCM) ground wire harness
from engine or main fuse before confirming diagnostic information (DTC, freeze frame data, etc.) stored in
ECM (PCM) memory. Such disconnection will erase memorized information in ECM (PCM) memory.
• Diagnostic information stored in ECM (PCM) 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 without monitor connector)
If two or more diagnostic trouble codes (DTCs) are stored, proceed to the flow table of the DTC which was
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/P0174/P0175 (Fuel system too lean/too
rich), DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire detected) and DTC P0400 (EGR
flow malfunction)
– DTC P0171/P0172/P0174/P0175 (Fuel system too lean/too rich) and DTC P0400 (EGR flow malfunction)
– DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire detected)
• Be sure to read “PRECAUTIONS FOR ELECTRICAL CIRCUIT SERVICE” in Section 0A before inspection
and observe what is written there.
• ECM (PCM) Replacement
When substituting a known-good ECM (PCM), check for following conditions. Neglecting this check may
cause damage to a known-good ECM (PCM).
– Resistance value of all relays, actuators is as specified respectively.
– MAF sensor, MAP sensor and TP sensor are in good condition and none of power circuits of these sen-
sors is shorted to ground.
2. B+
3. SUZUKI Serial data line
4. K line of ISO 9141
5. Body ground
6. ECM ground
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
6-1-28 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
TP SENSOR VOLT (TP Sensor Output Voltage, V)
Throttle Position Sensor reading provides throttle valve opening information in the from of voltage.
O2S B1 S1 (HO2S Bank 1 Sensor 1 Output Voltage, V) / O2S B2 S1 (HO2S Bank 2 Sensor 1 Output
Voltage, V)
It indicates output voltage of HO2S SENSOR 1 installed on exhaust manifold (pre-catalyst).
O2S B1 S2 (HO2S Bank 1 Sensor 2 Output Voltage, V) / O2S B2 S2 (HO2S Bank 2 Sensor 2 Output
Voltage, V)
If indicates output voltage of HO2S SENSOR 2 installed on exhaust pipe (post-catalyst). It is used to detect cat-
alyst deterioration.
FUEL SYSTEM B1 (Fuel System Bank 1 Status) / Fuel System B2 (Fuel System Bank 2 Status)
Air/fuel ratio feedback loop status displayed as one of the followings.
OPEN : Open loop-has not yet satisfied conditions to go closed loop.
CLOSED : Closed loop-using oxygen sensor(s) as feedback for fuel control.
OPEN-DRIVE COND : Open loop due to driving conditions (Power enrichment, etc.).
OPEN SYS FAULT : Open loop due to detected system fault.
CLOSED-ONE O2S : Closed loop, but fault with at least one oxygen sensor may be using single oxygen sensor
for fuel control.
CALC LOAD (Calculated Load Value, %)
Engine load displayed as a percentage of maximum possible load. Value is calculated mathematically using the
formula : actual (current) intake air volume ÷ maximum possible intake air volume x 100%.
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.
CANIST PRG DUTY (EVAP Canister Purge Flow Duty, %)
This parameter indicates valve ON (valve open) time rate within a certain set cycle of EVAP canister purge valve
which controls the amount of EVAP purge.
VEHICLE SPEED (km/h, MPH)
It is computed based on pulse signals from vehicle speed sensor on transfer or transmission.
FUEL CUT (ON/OFF)
ON : Fuel being cut (output signal to injector is stopped).
OFF : Fuel not being cut.
MAP (Manifold Absolute Pressure, mmHg, kPa)
This parameter indicates the pressure in the intake manifold absolute pressure.
A/C CONDENSER FAN (ON/OFF)
This parameter indicates the state of the A/C Condenser Fan control signal.
BLOWER FAN (ON/OFF)
This parameter indicates the state of the blower fan motor switch.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-39
C51-3-9 Throttle position sensor0.5 – 1.2 VIgnition switch ON, Throttle valve at
idle position
3.4 – 4.7 VIgnition switch ON, Throttle valve at
full open position
C51-3-10 Mass air flow sensor1.0 – 1.6 V Ignition switch ON and engine stops
1.7 – 2.0 V With engine running at idle speed
C51-3-11Heated oxygen sensor-1 (bank 1)
(if equipped)Deflects between
over and under 0.45 VWhile engine running at 2,000 r/min.
for 1 min. or longer after warmed up
C51-3-12 Ground for TP sensor – –
C51-3-13 Power source for TP sensor
4.75 – 5.25 V Ignition switch ON
C51-3-14 Power source for MAP sensor
C51-3-15 Power source 10 – 14 V Ignition switch ON
C51-3-16 – – –
C51-3-17 Ground – –
C51-3-18Pressure switch in 4WD air pump
assembly10 – 14 VIgnition switch ON, Transfer lever :
4H or 4L range
0 – 1 VIgnition switch ON, Transfer lever :
2H range
C51-3-19 – – –
C51-3-20 Ignition switch 10 – 14 V Ignition switch ON
C51-3-21Heated oxygen sensor-1 (bank 2)
(if equipped)Deflects between over
and under 0.45 VWhile engine running at 2,000 r/min.
for 1 min. or longer after warmed up
C51-3-22Heated oxygen sensor-2 (bank 1)
(if equipped)Deflects between over
and under 0.45 VWhile engine running at 2,000 r/min.
for 1 min. or longer after warmed up
C51-3-23Heated oxygen sensor-2 (bank 2)
(if equipped)Deflects between over
and under 0.45 VWhile engine running at 2,000 r/min.
for 1 min. or longer after warmed up
C51-3-24 Ground for ECT sensor – –
C51-3-25 Ground for IAT sensor, MAP sensor – –
C51-3-26 Ground for CMP sensor – –
C51-1-1 Shift solenoid B (A/T vehicle) 0 – 1 V Ignition switch ON
C51-1-2 Shift solenoid A (A/T vehicle) 10 – 14 V Ignition switch ON
C51-1-3 – – –
C51-1-4 IAC valve (stepper motor coil 2) – –
C51-1-5 IAC valve (stepper motor coil 1) – –
C51-1-6Transmission range switch “R”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“R” range
0 – 1 VIgnition switch ON, selector lever :
Other than “R”
C51-1-7Transmission range switch “P”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“P” range
0 – 1 VIgnition switch ON, selector lever :
Other than “P” range
C51-1-8 TCC solenoid (A/T vehicle) 0 – 1 V Ignition switch ON
C51-1-9 4WD air pump assembly10 – 14 VIgnition switch ON, Transfer lever :
4H or 4L range
0 – 1 VIgnition switch ON, Transfer lever :
2H range TERMINAL CIRCUIT NORMAL VOLTAGE CONDITION
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-89
DTC P0400 Exhaust Gas Recirculation Flow Malfunction
SYSTEM/WIRING DIAGRAM
1. EGR valve 5. ECM (PC)
2. Intake manifold 6. MAP sensor
3. Exhaust gas 7. Main fuse
4. Sensed information 8. Main relay
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-91
TROUBLESHOOTING
Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE” in this
section.
2 Is there DTC P0403 (EGR circuit malfunction)? Go to DTC P0403 Diag.
Flow Table.Go to Step 3.
3 Do you have SUZUKI scan tool? Go to Step 4. Go to Step 6.
4 EGR valve operation check :
1) With ignition switch OFF, install SUZUKI
scan tool.
2) Check EGR system referring to Section
6E2.
Is it in good condition?Go to Step 5. Go to Step 6.
5 MAP sensor check :
1) Check MAP sensor for performance refer-
ring to Section 6E2.
Is check result satisfactory?Intermittent trouble or
faulty ECM (PCM). Check
for intermittent referring to
“INTERMITTENT AND
POOR CONNECTION” in
Section 0A.Repair or replace.
6 EGR valve power supply circuit check :
1) With ignition switch OFF, disconnect EGR
valve coupler.
2) With ignition switch ON, check voltage
between C04-2 and ground, C04-5 and
ground.
Is each voltage 10 – 14 V?Go to Step 7. Faulty “BLU/BLK” wire.
7 EGR valve stepper motor coil circuit check :
1) With ignition switch OFF, connect EGR
valve coupler and disconnect ECM (PCM)
couplers.
2) Check resistance between C51-3-4 and
C51-2-12, C51-2-13, C51-2-14, C51-2-15.
Is each resistance 20 – 24 Ω at 20°C (68°F)?Go to Step 8. Faulty EGR valve.
8 MAP sensor check :
1) Check MAP sensor for performance refer-
ring to Section 6E2.
Is check result satisfactory?EGR passage clogged or
EGR valve malfunction.
If all above are OK, inter-
mittent trouble or faulty
ECM (PCM).
Check for intermittent
referring to “INTERMIT-
TENT AND POOR CON-
NECTION” in Section 0A.Repair or replace.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-111
DTC P1408 Manifold Absolute Pressure Sensor Circuit Malfunction
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1. MAP sensor
2. ECM (PCM)
DTC DETECTING CONDITION TROUBLE AREA
•While engine is running after being warmed up and
with throttle opening smaller than specification,
higher than 4.6 V manifold absolute pressure sen-
sor output voltage is detected for specified time or
with throttle opening larger than specification, lower
than 0.2 V manifold absolute pressure output volt-
age is detected for specified time.
(2 driving cycle detection logic)•Manifold absolute pressure sensor
•Manifold absolute pressure sensor vacuum pas-
sage
•ECM (PCM)
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester, on a level road.
NOTE:
Check to make sure that following condition is satisfied when using this “DTC CONFIRMATION PRO-
CEDURE”.
Intake air temp. : – 8°C (18°F) or higher
Engine coolant temp. : – 8 – 110°C (18 – 230°F)
Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)