Air intake temperature SUZUKI SWIFT 2008 2.G Service Workshop Manual

Downloaded from www.Manualslib.com manuals search engine 0A-1 General Information:
General Information
General Information
General Description
AbbreviationsS7RS0B0101001
A:
ABDC: After Bottom Dead Center
ABS: Anti-lock Brake System
AC: Alternating Current
A/C: Air Conditioning
A-ELR: Automatic-Emergency Locking Retractor
A/F: Air Fuel Mixture Ratio
ALR: Automatic Locking Retractor
API: American Petroleum Institute
APP sensor: Accelerator Pedal Position Sensor
A/T: Automatic Transmission , Automatic Transaxle
AT D C : After Top Dead Center
ATF: Automatic Transmission Fluid, Automatic
Transaxle Fluid
B:
B+: Battery Positive Voltage
BBDC: Before Bottom Dead Center
BCM: Body Electrical Control Module
BDC: Bottom Dead Center
BTDC: Before Top Dead Center
C:
CAN: Controller Area Network
CKT: Circuit
CKP Sensor: Crankshaft Position Sensor
CMP Sensor: Camshaft Position Sensor
CO: Carbon Monoxide
CPP Switch: Clutch Pedal Position Switch (Clutch
Switch, Clutch Start Switch)
CPU: Central Processing Unit
CRS: Child Restraint System
D:
DC: Direct Current
DLC: Data Link Connector (Assembly Line Diag. Link,
ALDL, Serial Data Link, SDL)
DOHC: Double Over Head Camshaft
DOJ: Double Offset Joint
DRL: Daytime Running Light
DTC: Diagnostic Trouble Code (Diagnostic Code)
E:
EBCM: Electronic Brake Cont rol Module, ABS Control
Module
EBD: Electronic Brake Force Distribution
ECM: Engine Control Module
ECT Sensor: Engine Coolant Temperature Sensor (Water Temp. Sensor, WTS)
EFE Heater: Early Fuel Evaporation Heater (Positive
Temperature Coefficient, PTC Heater)
EGR: Exhaust Gas Recirculation
EGRT Sensor: EGR Temperature Sensor (Recirculated
Exhaust Gas Temp. Sensor, REGTS)
ELR: Emergency Locking Retractor
ESP ®: Electronic Stability Program
EPS: Electronic Power Steering
EVAP: Evaporative Emission EVAP Canister:
Evaporative Emission Canister
(Charcoal Canister)
F:
4WD: 4 Wheel
Drive
G:
GEN: Generator
GND: Ground
GPS: Global Positioning System
H:
HVAC: Heating, Ventilating and Air Conditioning
HC: Hydrocarbons
HO2S: Heated Oxygen Sensor
I:
IAC Valve: Idle Air Control Valve (Idle Speed Control
Solenoid Valve, ISC Solenoid Valve)
IAT Sensor: Intake Air Temperature Sensor (Air
temperature Sensor, ATS)
ICM: Immobilizer Control Module
IG: Ignition
ISC Actuator: Idle Speed Control Actuator
L:
LH: Left Hand
LHD: Left Hand Drive Vehicle
LSPV: Load Sensing Proportioning Valve
M:
MAF Sensor: Mass Air Flow Sensor (Air Flow Sensor, AFS, Air Flow Meter, AFM)
MAP Sensor: Manifold Absolute Pressure Sensor
(Pressure Sensor, PS)
Max: Maximum
MFI: Multiport Fuel Injection (Mu ltipoint Fuel Injection)
Min: Minimum
MIL: Malfunction Indicator Lamp (“SERVICE ENGINE
SOON” Light)
M/T: Manual Transmission, Manual Transaxle
N:
NOx: Nitrogen Oxides
O:
OBD: On-Board Diagnostic System (Self-Diagnosis
Function)
O/D: Overdrive
OHC: Over Head Camshaft
O2S: Oxygen Sensor
P:
PCM: Powertrain Control Module
PCV: Positive Crankcase Ventilation
PNP: Park / Neutral Position
P/S: Power Steering
PSP Switch: Power Steering Pressure Switch (P/S
Pressure Switch)
R:
RH: Right Hand
RHD: Right Hand Drive Vehicle
S:
SAE: Society of Automotive Engineers

Downloaded from www.Manualslib.com manuals search engine Table of Contents 1- i
1
Section 1
CONTENTS
Engine
Precautions ................................................. 1-1
Precautions............................................................. 1-1
Precautions for Engine .......................................... 1-1
Engine General Information and
Diagnosis ............. .................................... 1A-1
Precautions........................................................... 1A-1
Precautions on Engine Service ........................... 1A-1
Precaution on On-Board Diagnostic (OBD) System .............................................................. 1A-1
Precautions in Diagnosing Trouble ..................... 1A-1
Precautions of ECM Circuit Inspection................ 1A-2
Precautions of Electric Throttle Body System
Calibration ......................................................... 1A-2
General Description ............................................. 1A-2 Statement on Cleanliness and Care ................... 1A-2
Engine Diagnosis General Description ............... 1A-3
On-Board Diagnostic System Description ........... 1A-3
Data Link Connector (DLC) ................................. 1A-6
Engine and Emission Control System Description ........................................................ 1A-6
CAN Communication System Description........... 1A-7
Air Intake System Description ............................. 1A-9
Description of Electric Throttle Body System ...... 1A-9
Description of Electric Throttle Body System Calibration ....................................................... 1A-10
Fuel Cut Control Description ............................. 1A-10
Generator Control System Description ............. 1A-11
Electronic Control System Description .............. 1A-12
Engine and Emission Control Input / Output Table ............................................................... 1A-18
Schematic and Routing Diagram ...................... 1A-19 Engine and Emission Control System Diagram .......................................................... 1A-19
Component Locatio n ......................................... 1A-21
Electronic Control System Components Location .......................................................... 1A-21
Diagnostic Information and Procedures .......... 1A-22 Engine and Emission Control System Check.... 1A-22
Malfunction Indicator Lamp (MIL) Check .......... 1A-25
DTC Check ....................................................... 1A-26
DTC Clearance ................................................. 1A-27
DTC Table ......................................................... 1A-27
Fail-Safe Table ................ .................................. 1A-31 Scan Tool Data ................................................. 1A-33
Visual Inspection ............................................... 1A-37
Engine Basic Inspection .................................... 1A-38
Engine Symptom Diagnosis .............................. 1A-41
MIL Does Not Come ON with Ignition Switch
ON and Engine Stop (but Engine Can Be
Started) ........................................................... 1A-47
Malfunction Indicator Lamp Remains ON after Engine Starts................................................... 1A-48
DTC P0010: “A” Camshaft Position Actuator Circuit .............................................................. 1A-49
DTC P0011 / P0012: “A” Camshaft Position - Timing Over-Advanced or System
Performance / -Retarded................................. 1A-52
DTC P0031 / P0032: HO2S Heater Control Circuit Low / High (Sensor-1) .......................... 1A-54
DTC P0037 / P0038: HO2S Heater Control Circuit Low / High (Sensor-2) .......................... 1A-56
DTC P0101: Mass or Volume Air Flow Circuit Range / Performance ...................................... 1A-58
DTC P0102: Mass or Volume Air Flow Circuit Low Input......................................................... 1A-61
DTC P0103: Mass or Volume Air Flow Circuit High Input ........................................................ 1A-63
DTC P0106: Manifold Absolute Pressure /
Barometric Pressure Circuit Range /
Performance.................................................... 1A-64
DTC P0107: Manifold Absolute Pressure /
Barometric Pressure Circ uit Low Input............ 1A-66
DTC P0108: Manifold Absolute Pressure /
Barometric Pressure Circ uit High Input ........... 1A-67
DTC P0111: Intake Air Temperature Sensor 1 Circuit Range / Performance ........................... 1A-69
DTC P0112: Intake Air Temperature Sensor 1 Circuit Low ...................................................... 1A-72
DTC P0113: Intake Air Temperature 1 Sensor Circuit High...................................................... 1A-74
DTC P0116: Engine Coolant Temperature Circuit Range / Performance ........................... 1A-76
DTC P0117: Engine Coolant Temperature Circuit Low ...................................................... 1A-79
DTC P0118: Engine Coolant Temperature Circuit High...................................................... 1A-81
DTC P0122: Throttle / Pedal Position Sensor / Switch “A” (Main) Circuit Low ........................ 1A-83

Downloaded from www.Manualslib.com manuals search engine 1A-28 Engine General Information and Diagnosis:
) *P0031 HO2S heater control circuit low
(Sensor-1) Heater voltage is less than specification while heater ON. 2 driving
cycles
) *P0032 HO2S heater control circuit
high (Sensor-1) Heater voltage is more than
specification while heater
ON. 2 driving
cycles
) *P0037 HO2S heater control circuit low
(Sensor-2) Heater voltage is less than specification while heater ON. 2 driving
cycles
) *P0038 HO2S heater control circuit
high (Sensor-2) Heater voltage is more than
specification while heater
ON. 2 driving
cycles
)
U *P0101 Mass or volume air flow circuit
range/performance MAF sensor volume is more
than specification or less
than specification. 2 driving
cycles
) *P0102 Mass or volume air flow circuit
low input Output voltage of MAF sensor is less than specification. 1 driving
cycle
) *P0103 Mass or volume air flow circuit
high input Output voltage of MAF sensor is more than specification. 1 driving
cycle
)
U *P0106 Manifold absolute pressure/
barometric pressure circuit
range/performance Difference between Max. manifold absolute pressure
value and Min. manifold pressure value is less than
specification or difference between barometric pressure
value and manifold pressure value is less than
specification
2 driving
cycles
) *P0107 Manifold absolute pressure/
barometric pressure circuit low
input Output voltage of MAP sensor
is less than specification.1 driving
cycle
) *P0108 Manifold absolute pressure/
barometric pressure circuit high
input Output voltage of MAP sensor is more than specification.
1 driving
cycle
)
U *P0111 Intake air temperature sensor 1
circuit range/performance Variation of intake air temperature from engine start is
less than specification. 2 driving
cycles
) *P0112 Intake air temperature sensor 1
circuit low Circuit voltage of IAT sensor is less than specification. 1 driving
cycle
) *P0113 Intake air temperature sensor 1
circuit hig

h Circuit voltage of IAT sensor
is more than specification. 1 driving
cycle
)
U *P0116 Engine coolant temperature
circuit range/performance Engine coolant temperature is less than specified
temperature for specified time from engine start. 2 driving
cycles
) *P0117 Engine coolant temperature
circuit low Circuit voltage of ECT sensor
is less than specification. 1 driving
cycle
) *P0118 Engine coolant temperature
circuit high Circuit voltage of ECT sensor
is more than specification. 1 driving
cycle
) *P0122 Throttle/pedal position sensor/
switch “A” circuit low Output voltage of TP sensor (main) is lower than
specification. 1 driving
cycle
) *P0123 Throttle/pedal position sensor/
switch “A” circuit high Output voltage of TP sensor (main) is higher than
specification. 1 driving
cycle
)
U *P0131 O2 sensor (HO2S) circuit low
voltage (Sensor-1)
Max. output voltage of HO2S-1
is less than specification.2 driving
cycles
)
U *P0132 O2 sensor (HO2S) circuit high
voltage (Sensor-1)
Min. output voltage of HO2S-1
is more than specification. 2 driving
cycles
)
U *P0133 O2 sensor (HO2S) circuit slow
response (Sensor-1) Response time of HO2S-1 output voltage between rich
and lean is longer than specification. 2 driving
cycles
) *P0134 O2 sensor (HO2S) circuit no
activity detected (Sensor-1) Output voltage of HO2S-1 is
more than specification or
less than specification. (or HO2S-1 circuit open or short) 2 driving
cycles
)
U *P0137 O2 sensor (HO2S) circuit low
voltage (Sensor-2) Output voltage of HO2S-2 is
less than specification while
engine is idling after driving with high engine load and
Max. output voltage of HO2S-2 minus Min. output voltage
of HO2S-2 is less than specification. 2 driving
cycles
)
U *P013

8 O2 sensor (HO2S) circuit high
voltage (Sensor-2) Output voltage of HO2S-2 is
more than specification while
engine is idling after driving with high engine load and
Max. output voltage of HO2S-2 minus Min. output voltage
of HO2S-2 is less than specification. 2 driving
cycles
DTC No. Detecting item
Detecting condition
(DTC will set when detecting:) MIL

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Fail-Safe TableS7RS0B1104006
When any of the following DTCs is detected, ECM enters fail-safe mode as long as malfunction continues to exist but
that mode is canceled when ECM de tects normal condition after that.
)
*P2123 Throttle/pedal position sensor/
switch “D” (main) circuit high
input Output voltage of APP sensor (main) is higher than
specification.
1 driving
cycle
) *P2127 Throttle/pedal position sensor/
switch “E” (sub) circuit low
input Output voltage of APP sens
or (sub) is lower than
specification. 1 driving
cycle
) *P2128 Throttle/pedal position sensor/
switch “E” (sub) circuit high
input Output voltage of APP sensor (sub) is higher than
specification.
1 driving
cycle
) *P2135 Throttle/pedal position sensor/
switch “A”/“B” (main / sub)
voltage correlation Difference between the opening angle based on TP
sensor (main) and the opening angle based on TP sensor
(sub) is more than specification.
1 driving
cycle
) *P2138 Throttle/pedal position sensor/
switch “D”/“E” (main / sub)
voltage correlation Difference between the opening angle based on APP
sensor (main) and the opening angle based on APP
sensor (sub) is more
than specification. 1 driving
cycle
)
U *P2227 Barometric pressure circuit
range/performance Difference of barometric pressure value and intake
manifold pressure value is
more than specification at
engine start. 2 driving
cycles
) *P2228 Barometric pressure circuit low Barometric pressure sens
or voltage is less than
specification. 1 driving
cycle
) *P2229 Barometric pressure circuit
high Barometric pressure sensor voltage is more than
specification. 1 driving
cycle
) P1614 Transponder response error
Refer to “Diagnostic Trouble Code (DTC) Table in Section
10C”. —

) P1615 ID code does not registered
(vehicle equipped with keyless
start system only)
) P1616 Different registration ID codes
(vehicle equipped with keyless
start system only)
) P1618 CAN communication error
(reception error for keyless
start control module) (vehicle
equipped with keyless start
system only)
) P1621 Immobilizer communication
line error
) P1622
EEPROM error
) P1623 Unregistered transponder
) P1625 Immobilizer antenna error
) P1636 Immobilizer information
registration failure
) P1638 Immobilizer information
mismatched
DTC No. Detecting item
Detecting condition
(DTC will set when detecting:) MIL
DTC No.
Detected item Fail-safe operation
) P0031 HO2S heater control circuit low (Sensor-1)
ECM stops air/fuel ratio control.
) P0032 HO2S heater control circuit high (Sensor-1)
) P0102 Mass or volume air flow circuit low input • ECM controls injector drive time (fuel injection
volume) according to throttle valve opening
(closed throttle position or not).
• ECM stops EGR control.
)
P0103 Mass or volume air flow circuit high input
) P0112 Intake air temperature sensor 1 circuit low ECM controls actuators assuming that intake air
temperature is 20 °C (68 ° F).
) P0113 Intake air temperature sensor 1 circuit high

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-35
Scan Tool Data Definitions
COOLANT TEMP (ENGINE COOLANT
TEMPERATURE, °C, °F)
It is detected by engine coolant temp. sensor.
INTAKE AIR TEMP. ( °C, °F)
It is detected by intake air temp. sensor.
ENGINE SPEED (rpm)
It is computed by reference pulses from the camshaft
position sensor.
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 fo r multiport fuel injection).
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.
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
Short term fuel trim valu e represents short term
corrections to the air/fuel mixture computation. A value
of 0 indicates 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, %)
Long term fuel trim value represents long term
corrections to the air/fuel mixture computation. A value
of 0 indicates no correction, a value greater than 0
means an enrichment correction, and a value less than 0
implies an enleanment correction.
TOTAL FUEL TRIM B1 (%)
The value of Total Fuel Trim is obtained by calculating
based on values of Short Term Fuel Trim and Long Term
Fuel Trim. This value indica
tes how much correction is
necessary to keep the air/fuel mixture stoichiometrical.
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.
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 × 100%
THROTTLE POS (ABSOLUTE THROTTLE POSITION,
%)
When throttle position sensor is at fully closed position,
throttle opening is indicated as 0 – 5% and 90 – 100%
full open position.
O2S SENSOR B1 S1 (HEA TED OXYGEN SENSOR-1,
V)
It indicates output voltage of HO2S-1 installed on
exhaust manifold (pre-catalyst).
)
TP SENSOR 2 VOLT Ignition switch ON after
warmed up engine Accelerator pedal released
1.4 – 1.8 V
Accelerator pedal depressed
fully 3.58 – 4.76 V
) APP SENSOR 1
VOLT Ignition switch ON after
warmed up engineAccelerator pedal released
0.5 – 0.9 V
Accelerator pedal depressed
fully 3.277 – 3.915 V
) APP SENSOR 2
VOLT Ignition switch ON after
warmed up engineAccelerator pedal released
1.3 – 1.7 V
Accelerator pedal depressed
fully 4.077 – 4.715 V
) ACCEL POSITION Ignition switch ON after
warmed up engine Accelerator pedal released
0 – 5%
Accelerator pedal depressed
fully 90 – 100%
) THROTTLE TARGET
POSI Ignition switch ON after
warmed up engineAccelerator pedal released
0 – 5%
Accelerator pedal depressed
fully 90 – 100%
) BATTERY
CURRENT At specified idle speed with no load after warming up
5.0 – 60.0 A
) GENERATOR CONT
DUTY (GENERATOR
CONTROL DUTY) At specified idle speed with no load after warming up
20.0 – 100.0%
) GENERATOR FIELD
DUTY (GENERATOR
FIELD COIL DUTY) At spe
cified idle speed with no load after warming up
20.0 – 100.0%
Scan tool data
Vehicle condition Normal condition /
reference values

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-59
DTC Confirmation Procedure
WARNING!
• When performing a road test, select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
• Road test should be carried out by 2 persons, a driver and a tester, on a level road.

NOTE
Check to make sure that the following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Intake air temperature at engine start: –10 °C (14 °F) to 80 °C (176 °F)
• Intake air temperature: –10 °C (14 °F) to 70 °C (158 °F)
• Engine coolant temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature. (ECT approx. 90 – 95 °C, 194 – 203 °F)
4) Drive vehicle with engine speed: more than 2500 rpm for 1 min.
5) Increase vehicle speed to 80 km/h (45 mile/h) at 5th gear or D range.
6) Release accelerator pedal to decrease vehicle speed to 40 km/h (25 mile/h).
7) Stop vehicle and run it idle for 1 min.
8) Check DTC and pending DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

Step Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Visual inspection
Check MAF sensor and air intake system for:
• Objects which block measuring duct and resistor of MAF
sensor.
• Other air flow which does not pass the MAF sensor.
Are they in good condition? Go to Step 3.
Repair or replace.
3 MAF sensor and its circuit check
1) With ignition switch turned OFF, connect scan tool.
2) Start engine and warm up to normal operation
temperature.
3) Check MAF value using scan tool. (Refer to “Scan Tool Data” for normal value.)
Is each value within specified range? Go to Step 11. Go to Step 4.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-65
DTC Confirmation Procedure
NOTE
Check to make sure that the following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Intake air temperature at engine start: –10 °C (14 ° F) to 80 °C (176 °F)
• Intake air temperature: –10 °C (14 °F) to 70 °C (158 °F)
• Engine coolant temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC using scan tool and warm up engine completely.
3) Increase engine speed up to 2000 rpm or more for 10 seconds.
4) Run engine at idle speed for 1 min.
5) Check DTC and pending DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

Step Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 MAP sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ON ignition switch.
3) Check DTC.
Is there DTC P0107 or DTC P0108? Go to applicable DTC
diag. flow.
Go to Step 3.
3 MAP sensor output signal check
1) Check MAP sensor acco rding to “MAP Sensor
Inspection in Section 1C”.
Is it in good condition? Go to Step 4.
Faulty MAP sensor.
4 MAP sensor circuit check
1) Check MAP sensor circuit referring to Step 3 to 6 of
“DTC P0107: Manifold Absolute Pressure / Barometric
Pressure Circuit Low Input” or Step 3 to 8 of “DTC
P0108: Manifold Absolute Pressure / Barometric
Pressure Circuit High Input”.
Is circuit in good condition? Go to Step 5.
Repair or replace.
5 Air intake system check
1) Check air intake system for clog or leak.
Is it in good condition? Substitute a known-
good ECM and recheck.
Repair or replace.

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DTC P0111: Intake Air Temperature Sensor 1 Circuit Range / PerformanceS7RS0B1104023
Wiring Diagram6
Ground circuit check
1) Measure resistance between “C37-55” terminal of ECM
connector and vehicle body ground.
Is resistance below 5
Ω? “ORN” wire is open or
high resistance circuit.
ECM grounds “E23-31”,
“C37-58”, “C37-15” and/
or “C37-30” circuit are
open or high resistance.
If wires are OK,
substitute a known-
good ECM and recheck.
7 MAP sensor signal circuit check
1) Turn ON ignition switch.
2) Measure voltage between “RED/BLK” wire terminal of
MAP sensor connector and engine ground.
Is voltage 4 – 6 V? Go to Step 9. Go to Step 8.
8 MAP sensor signal circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “RED/BLK” wire terminal of MAP sensor connector and “C37-53” terminal of ECM
connector.
Is resistance below 2
Ω? “RED/BLK” wire is
shorted to power supply
circuit.
“RED/BLK” wire is open
or high resistance
circuit.
9 MAP sensor output signal check
1) Check MAP sensor acco rding to “MAP Sensor
Inspection in Section 1C”.
Is it in good condition? Substitute a known-
good ECM and recheck.
Faulty MAP sensor.
Step Action Yes No
E23
C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
5V
2
BLK/YEL
GRY/BLU
GRY
ORN
1
GRN/BLK
C37-25
C37-55 3 4ORN
C37-26
C37-27
BLK/RED
I4RS0B110018-01
1. MAF and IAT sensor
3. To other sensors
2. ECM 4. From main relay

Downloaded from www.Manualslib.com manuals search engine 1A-70 Engine General Information and Diagnosis:
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
NOTE
Check to make sure that following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Intake air temperature at engine start: –10 °C (14 ° F) to 80 °C (176 °F)
• Intake air temperature: –10 °C (14 °F) to 70 °C (158 °F)
• Engine coolant temperature at engine start: less than 30 °C (86 °F)
• Engine coolant temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch, clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature. (ECT approx. 90 – 95 °C, 194 – 203 °F)
4) Run engine at idle speed for 10 min. or more.
5) Check DTC and pending DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

DTC detecting condition Trouble area
Difference of maximum IAT minus minimum IAT is less than 0.3 °C
(32.5 °F) while ECT is over 70 °C (158 °F) after 10 min from cold
engine start (ECT is lower than 30 °C (86 °F) at engine start).
(2 driving cycle detection logic) • High resistance circuit
• MAF and IAT sensor
•ECM
Step
Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 IAT sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ignition switch to ON position.
3) Check intake air temp. displayed on scan tool.
Is –40
°C (–40 °F) or 119 °C (246 °F) indicated? Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.

Downloaded from www.Manualslib.com manuals search engine 1A-72 Engine General Information and Diagnosis:
DTC P0112: Intake Air Temperature Sensor 1 Circuit LowS7RS0B1104024
Wiring Diagram
Refer to “DTC P0111: Intake Air Temperature Sensor 1 Circuit Range / Performance”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and run it for 10 sec.
4) Check DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

8 Ground circuit check
1) Connect connectors to ECM.
2) Check for proper connection of MAF and IAT sensor
connector at “GRY/BLU” wire terminal.
3) Measure resistance between “GRY/BLU” wire terminal of MAF and IAT sensor connector and vehicle body
ground with ignition switch turned OFF.
Is resistance below 5
Ω? Go to Step 10. Go to Step 9.
9 Ground circuit check
1) Remove ECM from its br acket with ECM connectors
connected.
2) Measure resistance between “C37-55” terminal of ECM connector and vehicle body ground.
Is resistance below 3
Ω? “GRY/BLU” wire and/or
“ORN” wire is open or
high resistance circuit.
Poor “C37-55”
connection.
Faulty ECM ground
circuit.
If circuit is OK,
substitute a known-
good ECM and recheck.
10 IAT sensor check
1) Check IAT sensor according to “MAF and IAT Sensor
Inspection in Section 1C”.
Is it in good condition? Substitute a known-
good ECM and recheck.
Replace MAF and IAT
sensor.
Step Action Yes No
DTC detecting condition
Trouble area
IAT sensor output voltage is less than 0.15 V for 0.5 seconds
continuously.
(High intake air temperature (low voltage/low resistance))
(1 driving cycle detection logic) • IAT sensor circuit
• IAT sensor
•ECM