temperature sensor SUZUKI SWIFT 2000 1.G RG413 Service User Guide

6-2 ENGINE GENERAL INFORMATION AND DIAGNOSIS
ENGINE DIAGNOSIS ......................................... 6-6
GENERAL DESCRIPTION ............................. 6-6
ON-BOARD DIAGNOSTIC SYSTEM
(VEHICLE WITH IMMOBILIZER INDICATOR
LAMP) ............................................................. 6-7
ON-BOARD DIAGNOSTIC SYSTEM
(VEHICLE WITHOUT IMMOBILIZER
INDICATOR LAMP) ...................................... 6-10
PRECAUTION IN DIAGNOSING
TROUBLE ..................................................... 6-11
ENGINE DIAGNOSTIC FLOW TABLE ......... 6-12
CUSTOMER PROBLEM INSPECTION
FORM (EXAMPLE) ................................... 6-14
MALFUNCTION INDICATOR LAMP (MIL)
CHECK...................................................... 6-15
DIAGNOSTIC TROUBLE CODE (DTC)
CHECK...................................................... 6-15
DIAGNOSTIC TROUBLE CODE (DTC)
CLEARANCE ............................................ 6-16
DIAGNOSTIC TROUBLE CODE (DTC)
TABLE ....................................................... 6-17
FAIL-SAFE TABLE.................................... 6-20
VISUAL INSPECTION .............................. 6-22
ENGINE BASIC INSPECTION.................. 6-23
ENGINE DIAGNOSIS TABLE ................... 6-26
SCAN TOOL DATA....................................... 6-31
INSPECTION OF ECM AND ITS
CIRCUITS ..................................................... 6-36
ECM VOLTAGE VALUES TABLE............. 6-37
TERMINAL RESISTANCE TABLE............ 6-43
COMPONENT LOCATION ........................... 6-45
TABLE A-1 MALFUNCTION INDICATOR
LAMP CIRCUIT CHECK - LAMP DOES NOT
COME “ON” AT IGNITION SWITCH ON
(BUT ENGINE AT STOP) ............................. 6-46
TABLE A-2 MALFUNCTION INDICATOR
LAMP CIRCUIT CHECK - LAMP REMAINS
“ON” AFTER ENGINE STARTS ................... 6-47
TABLE A-3 MIL CHECK - MIL FLASHES
AT IGNITION SWITCH ON (VEHICLE
WITHOUT IMMOBILIZER INDICATOR
LAMP) ........................................................... 6-48
TABLE A-4 MIL CHECK - MIL DOES NOT
FLASH OR JUST REMAINS ON EVEN
WITH GROUNDING DIAGNOSIS SWITCH
TERMINAL (VEHICLE WITHOUT
IMMOBILIZER INDICATOR LAMP) .............. 6-48
TABLE A-5 ECM POWER AND GROUND
CIRCUIT CHECK - MIL DOESN’T LIGHT
AT IGNITION SWITCH ON AND ENGINE
DOESN’T START THOUGH IT IS
CRANKED UP .............................................. 6-49
DTC P0105 (DTC NO.11) MANIFOLD
ABSOLUTE PRESSURE (MAP) CIRCUIT
MALFUNCTION ............................................ 6-52
DTC P0110 (DTC NO.18) INTAKE AIR
TEMP. (IAT) CIRCUIT MALFUNCTION ....... 6-55
DTC P0115 (DTC NO.19) ENGINE
COOLANT TEMPERATURE (ECT) CIRCUIT
MALFUNCTION ............................................ 6-57DTC P0120 (DTC NO.13) THROTTLE
POSITION CIRCUIT MALFUNCTION ........... 6-60
DTC P0121 THROTTLE POSITION CIRCUIT
RANGE/PERFORMANCE PROBLEM .......... 6-63
DTC P0130 (DTC NO.14) HEATED OXYGEN
SENSOR (HO2S) CIRCUIT MALFUNCTION
(SENSOR-1) .................................................. 6-66
DTC P0133 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT SLOW RESPONSE
(SENSOR-1) .................................................. 6-68
DTC P0134 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT NO ACTIVITY DETECTED
(SENSOR-1) .................................................. 6-69
DTC P0135 (DTC NO.14) HEATED OXYGEN
SENSOR (HO2S) HEATER CIRCUIT
MALFUNCTION (SENSOR-1) ....................... 6-70
DTC P0136 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT MALFUNCTION
(SENSOR-2) .................................................. 6-72
DTC P0141 HEATED OXYGEN SENSOR
(HO2S) HEATER CIRCUIT MALFUNCTION
(SENSOR-2) .................................................. 6-74
DTC P0171 FUEL SYSTEM TOO LEAN ....... 6-76
DTC P0172 FUEL SYSTEM TOO RICH ....... 6-76
DTC P0300 RANDOM MISFIRE DETECTED
(MISFIRE DETECTED AT 2 OR MORE
CYLINDERS) ................................................. 6-81
DTC P0301 CYLINDER 1 MISFIRE
DETECTED ................................................... 6-81
DTC P0302 CYLINDER 2 MISFIRE
DETECTED ................................................... 6-81
DTC P0303 CYLINDER 3 MISFIRE
DETECTED ................................................... 6-81
DTC P0304 CYLINDER 4 MISFIRE
DETECTED ................................................... 6-81
DTC P0325 (DTC NO.17) KNOCK SENSOR
CIRCUIT MALFUNCTION ............................. 6-86
DTC P0335 (DTC NO.23) CRANKSHAFT
POSITION (CKP) SENSOR CIRCUIT
MALFUNCTION ............................................. 6-88
DTC P0340 (DTC NO.15) CAMSHAFT
POSITION (CMP) SENSOR CIRCUIT
MALFUNCTION ............................................. 6-91
DTC P0400 EXHAUST GAS
RECIRCULATION FLOW MALFUNCTION ... 6-94
DTC P0420 CATALYST SYSTEM
EFFICIENCY BELOW THRESHOLD ............ 6-97
DTC P0443 PURGE CONTROL VALVE
CIRCUIT MALFUNCTION ........................... 6-100
DTC P0480 RADIATOR COOLING FAN
CONTROL SYSTEM MALFUNCTION ........ 6-101
DTC P0500 (DTC NO.16) VEHICLE SPEED
SENSOR (VSS) MALFUNCTION ................ 6-103
DTC P0505 (DTC NO.26) IDLE CONTROL
SYSTEM MALFUNCTION ........................... 6-105
DTC P1450 BAROMETRIC PRESSURE
SENSOR LOW/HIGH INPUT....................... 6-108
DTC P1451 BAROMETRIC PRESSURE
SENSOR PERFORMANCE PROBLEM ...... 6-108

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-11
DATA LINK CONNECTOR (DLC)
ELC (1) is in compliance with SAEJ1962 in its installation posi-
tion, the shape of connector and pin assignment.
Serial data line (K line of ISO 9141) is used for SUZUKI scan tool
(Tech-1) to communicate with ECM, TCM, ABS control module
and Air bag SDM.
SUZUKI serial data line is used for SUZUKI scan tool (Tech -1) to
communicate with immobilizer control module.
PRECAUTION IN DIAGNOSING TROUBLE
Do not disconnect couplers from ECM, battery cable from battery, ECM ground wire harness from engine or
main fuse before confirming diagnostic information (DTC, freeze frame data, etc.) stored in ECM memory.
Such disconnection will erase memorized information in ECM memory.
Diagnostic information stored in ECM memory can be cleared as well as checked by using SUZUKI scan
tool (Tech-1) or generic scan tool (Vehicle with immobilizer indicator lamp). 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 with immobilizer indicator lamp).
If two or more DTCs are stored, proceed to the flow table of the DTC which has detected earliest in the order
(it can be identified by referring to freeze frame data) 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 (Fuel system too lean/too rich), DTC
P0300/P0301/P0302/P0303/P0304 (Misfire detected) and DTC P0400 (EGR flow malfunction)
–DTC P0171/P0172 (Fuel system too lean/too rich) and DTC P0400 (EGR flow malfunction)
–DTC P0300/P0301/P0302/P0303/P0304 (Misfire detected)
Be sure to read “Precautions for Electrical Circuit Service” in Section 0A before inspection and observe what
is written there.
ECM Replacement
When substituting a known-good ECM, check for following conditions. Neglecting this check may cause
damage to a known-good ECM.
–Resistance value of all relays, actuators is as specified respectively.
–MAP sensor and TP sensor are in good condition and none of power circuits of these sensors is shorted
to ground.AMBIENT
TEMPERATURETIME TO CUT POWER TO ECM
Over 0°C (32°F) 60 sec. or longer
Under 0°C (32°F) Not specifiable. Select a place with
temperature higher than 0°C (32°F).
2. B+
3. Serial data line (K line of ISO 9141)
4. ECM ground
5. Body ground
6. SUZUKI serial data line
2
3456
1

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-17
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.DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
(vehicle
with immo-
bilizer indi-
cator lamp)MIL
(vehicle
without
immobi-
lizer indica-
tor lamp)
P0105
(No.11)Manifold absolute pressure
circuit malfunctionLow pressure-high vacuum-low voltage
(or MAP sensor circuit shorted to ground)
High pressure-low vacuum-high voltage
(or MAP sensor circuit open)1 driving
cycle1 driving
cycle
P0110
(No.18)Intake air temp. circuit mal-
functionIntake air temp. circuit low input
Intake air temp. circuit high input1 driving
cycle1 driving
cycle
P0115
(No.19)Engine coolant temp. cir-
cuit malfunctionEngine coolant temp. circuit low input
Engine coolant temp. circuit high input1 driving
cycle1 driving
cycle
P0120
(No.13)Throttle position circuit mal-
functionThrottle position circuit low input
Throttle position circuit high input1 driving
cycle1 driving
cycle
P0121 Throttle position circuit per-
formance problemPoor performance of TP sensor 2 driving
cyclesNot
applicable
P0130
(No.14)HO2S circuit malfunction
(Sensor-1)Min. output voltage of HO2S-higher than
specification
Max. output voltage of HO2S-lower than
specification2 driving
cycle1 driving
cycle
P0133 HO2S circuit slow response
(Sensor-1)Response time of HO2S-1 output voltage
between rich and lean is longer than spec-
ification.2 driving
cyclesNot
applicable
P0134 HO2S circuit no activity
detected (Sensor-1)Output voltage of HO2S-1 fails to go above
specification (or HO2S-1 circuit shorted to
ground).2 driving
cycles1 driving
cycle
P0135
(No.14)HO2S heater circuit mal-
function (Sensor-1)Terminal voltage is lower than specifica-
tion at heater OFF or it is higher at heater
ON.2 driving
cycles1 driving
cycle
P0136 HO2S circuit malfunction
(Sensor-2)Max. voltage of HO2S-2 is lower than
specification or its min. voltage is higher
than specification2 driving
cyclesNot
applicable

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-19
P1451 Barometric pressure sen-
sor performance problemDifference between manifold absolute
pressure (MAP sensor value) and baro-
metric pressure (barometric pressure sen-
sor value) is larger than specification
during cranking.2 driving
cyclesNot
applicable
P1500 Starter signal circuit mal-
functionStarter signal is not inputted from engine
cranking till its start and after or it is always
inputted2 driving
cyclesNot
applicable
P1510 ECM backup power source
malfunctionNo backup power after starting engine 1 driving
cycleNot
applicable
P1600 Serial communication prob-
lem between ECM and
TCMNo signal or check sum error while engine
running1 driving
cycleNot
applicable
P1717 AT D-range signal circuit
malfunctionNo “D” range (park/neutral position signal)
is inputted while vehicle running2 driving
cyclesNot
applicable DTC
NO.DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
(vehicle
with immo-
bilizer indi-
cator lamp)MIL
(vehicle
without
immobi-
lizer indica-
tor lamp)
DTC NO. DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
✱P0702 Transmission Control System Electrical
Refer to Section 7B ✱P0705 Transmission Range Sensor Circuit Malfunc-
tion
✱P0710 Transmission Fluid Temperature Sensor Cir-
cuit Malfunction
✱P0715 Input/turbine Speed Sensor Circuit Malfunc-
tion
✱P0720 Output Shaft Speed Sensor Circuit Malfunc-
tion
✱P0725 Engine Speed Input Circuit Malfunction
✱P0730 Incorrect Gear Ratio
✱P0741 Torque Converter Clutch System Perfor-
mance or Stuck Off
✱P0743 Torque Converter Clutch System Electrical
✱P0753 Shift Solenoid A Electrical
✱P0758 Shift Solenoid B Electrical
✱P0763 Shift Solenoid C Electrical
✱P0768 Shift Solenoid D Electrical
✱P0773 Shift Solenoid E Electrical
✱P1700 Throttle Position Signal Input Malfunction
✱P1702 Internal Control Module Memory Check Some
Error
✱P1709 Engine Coolant Temperature Signal Input
Malfunction

6-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS
FAIL-SAFE TABLE
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 detects normal condition after that.P1620
(No.84)ECU code not registered
Refer to Section 8G P1621
(No.83)No ECU code transmitted from Immobilizer
Control Module
P1622
(No.82)Fault in ECM
P1623
(No.81)ECU code not matched DTC NO. DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
NOTE:
For (
) marked No. in DTC column, it is used for vehicle without immobilizer indication lamp.
DTC No.12 appears when none of the other codes is identified.
For vehicle with immobilizer indication lamp, star (
✱) marked DTCs can be read with SUZUKI scan
tool ECM application.
DTC NO. TROUBLE AREA FAIL-SAFE OPERATION SYMPTOM
P0105
(No.11)MAP SENSOR ECM uses value determined by throt-
tle opening and engine speed.
ECM stops EGR, EVAP purge and
idle air control.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation/ poor acceleration/
surge/ detonation or spark knock
P0110
(No.18)IAT SENSOR ECM controls actuators assuming
that intake air temperature is 20°C.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation poor acceleration/ deto-
nation or spark knock
P0115
(No.19)ECT SENSOR ECM controls actuators assuming
that engine coolant temperature is
80°C.
Radiator fan motor ON.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation poor acceleration/ deto-
nation or spark knock
P0120
(No.13)TP SENSOR ECM controls actuators assuming
that throttle opening is 20°.Rough or incorrect idle/ excessive
fuel consumption/ hesitation/ poor
acceleration
P0130,
P0134
(No.14)HEATED OXYGEN
SENOR-1–Hard starting/rough or incorrect
idle/ excessive fuel consumption/
hesitation/ poor acceleration
P0325
(No.17)KNOCK SENSOR–Detonation/ spark knock
P0335
(No.23)CKP SENSORFix ignition timing.
ECM changes injection control sys-
tem from sequential injection to
simultaneous one.Hard staring/ engine stall

6-30 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Improper engine
idling or engine fails
to idleFaulty spark plug Spark plugs in Section 6F1.
Leaky or disconnected high-tension cord High-tension cords in Section 6F1.
Faulty ignition coil with ignitor Ignition coil in Section 6F1.
Fuel pressure out of specification Diagnostic Flow Table B-3.
Leaky manifold, throttle body, or cylinder
head gasket
Malfunctioning EGR valve (if equipped) EGR system in Section 6E1.
Faulty idle air control system Diagnostic Flow Table B-4.
Faulty evaporative emission control system EVAP control system in Section 6E1.
Faulty EGR system (if equipped) EGR system in Section 6E1.
Faulty fuel injector(s) Diagnostic Flow Table B-1.
Poor performance of ECT sensor, TP sensor
or MAP sensorECT sensor, TP sensor or MAP sensor
in Section 6E1.
Faulty ECM
Loose connection or disconnection of vacuum
hoses
Malfunctioning PCV valve PCV system in Section 6E1.
Engine overheating Refer to “Overheating” section.
Low compression Previously outlined.
Excessive hydrocar-
bon (HC) emission
or carbon monox-
ide (CO)Faulty spark plug Spark plugs in Section 6F1.
Leaky or disconnected high-tension cord High-tension cords in Section 6F1.
Faulty ignition coil with ignitor Ignition coil assembly in Section 6F1.
Low compression Refer to “Low compression” section.
Lead contamination of three way catalytic
converterCheck for absence of filler neck restric-
tor.
Faulty evaporative emission control system EVAP control system in Section 6E1.
Fuel pressure out of specification Diagnostic Flow Table B-3.
Closed loop system (A/F feed back compen-
sation) fails
Faulty TP sensor
Poor performance of ECT sensor or MAP
sensorTP sensor in Section 6E1.
ECT sensor or MAP sensor in Section
6E1.
Faulty injector(s) Diagnostic Flow Table B-1
Faulty ECM
Engine not at normal operating temperature
Clogged air cleaner
Vacuum leaks
Excessive nitrogen
oxides (NOx) emis-
sionImproper ignition timing See section 6F1.
Lead contamination of catalytic converter Check for absence of filler neck restric-
tor.
Faulty EGR system (if equipped) EGR system in Section 6E1.
Fuel pressure out of specification Diagnostic Flow Table B-3.
Closed loop system (A/F feed back compen-
sation) fails
Faulty TP sensor
Poor performance of ECT sensor or MAP
sensorTP sensor in Section 6E1.
ECT sensor or MAP sensor in Section
6E1.
Faulty injector(s) Diagnostic Flow Table B-1
Faulty ECM Condition Possible Cause Correction

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-33
SCAN TOOL DATA DEFINITIONS :
FUEL SYSTEM (FUEL SYSTEM STATUS)
Air/fuel ratio feedback loop status displayed as either open or closed loop. Open indicates that ECM ignores
feedback from the exhaust oxygen sensor.
Closed indicates final injection duration is corrected for oxygen sensor feedback.
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%.
COOLANT TEMP. (ENGINE COOLANT TEMPERATURE, °C, °F)
It is detected by engine coolant temp. sensor
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
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, %)
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.
MAP (INTAKE MANIFOLD ABSOLUTE PRESSURE, kPa, inHg)
It is detected by manifold absolute pressure sensor and used (among other things) to compute engine load.
ENGINE SPEED (rpm)
It is computed by reference pulses from crankshaft position sensor.
VEHICLE SPEED (km/h, MPH)
It is computed based on pulse signals from vehicle speed sensor.PNP SIGNAL (PARK/NEU-
TRAL POSITION SIGNAL)
A/T onlyIgnition switch
ONSelector lever in “P” or “N”
positionP/N Range
Selector lever in “R”, “D”,
“2” or “L” positionD Range
EGR VALVE At specified idle speed after warming up 0%
∆FUEL TANK LEVEL–0 – 100%
BAROMETRIC PRESS–Display the barometric pres-
sure
FUEL PUMP Within 3 seconds after ignition switch ON or
engine runningON
Engine stop at ignition switch ON. OFF
BRAKE SW Ignition switch
ONBrake pedal is depressing ON
Brake pedal is releasing OFF
BLOWER FAN Ignition switch
ONBlower fan switch ON ON
Blower fan switch OFF OFF
A/C MAG CLUTCH Ignition switch
ONA/C switch ON ON
A/C switch OFF OFF SCAN TOOL DATA VEHICLE CONDITION NORMAL CONDITION/
REFERENCE VALUES

6-34 ENGINE GENERAL INFORMATION AND DIAGNOSIS
IGNITION ADVANCE (IGNITION TIMING ADVANCE FOR NO.1 CYLINDER, °)
Ignition timing of NO.1 cylinder is commanded by ECM. The actual ignition timing should be checked by using
the timing light.
INTAKE AIR TEMP. (°C, °F)
It is detected by intake air temp. sensor and used to determine the amount of air passing into the intake manifold
as air density varies with temperature.
MAF (MASS AIR FLOW RATE, gm/s, lb/min)
It represents total mass of air entering intake manifold which is computed based on signals from MAP sensor,
IAT sensor, TP sensor, etc.
THROTTLE POS (ABSOLUTE THROTTLE POSITION, %)
When throttle position sensor is fully closed position, throttle opening is indicated as 0% and 100% full open
position.
OXYGEN SENSOR B1 S1 (HEATED OXYGEN SENSOR-1, V)
It indicates output voltage of HO2S-1 installed on exhaust manifold (pre-catalyst).
OXYGEN SENSOR B1 S2 (HEATED OXYGEN SENSOR-2, V)
It indicates output voltage of HO2S-2 installed on exhaust pipe (post-catalyst). It is used to detect catalyst dete-
rioration.
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.
TP SENSOR VOLT (THROTTLE POSITION SENSOR OUTPUT VOLTAGE, V)
The Throttle Position Sensor reading provides throttle valve opening information in the form of voltage.
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 for multiport fuel injection).
IAC FLOW DUTY (IDLE AIR (SPEED) CONTROL DUTY, %)
This parameter indicates current flow time rate within a certain set cycle of IAC valve (valve opening rate) which
controls the amount of bypass air (idle speed).
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.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage inputted from main relay to ECM.
CANIST PURGE DUTY (EVAP CANISTER PURGE FLOW DUTY, %)
This parameter indicates valve ON (valve open) time rate within a certain set cycle of EVAP purge solenoid
valve which controls the amount of EVAP purge.
0% means that the purge valve is completely closed while 100% is a fully open valve.
CLOSED THROTTLE POSITION (ON/OFF)
This parameter will read ON when throttle valve is fully closed, or OFF when the throttle is not fully closed.
FUEL CUT (ON/OFF)
ON : Fuel being cut (output signal to injector is stopped)
OFF : Fuel not being cut

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-55
DTC P0110 (DTC NO.18) INTAKE AIR TEMP. (IAT) CIRCUIT MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode no scan tool and check DTC.
INSPECTION
C42-10
C42-15
5V
ECM
LT GRN/BLK
ORN
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
DTC DETECTING CONDITION POSSIBLE CAUSE
Low intake air temperature (High voltage-High resistance)
or
High intake air temperature (Low voltage-Low resistance)“LT GRN/BLK” circuit open or shorted to
power.
“ORN” circuit open
IAT sensor malfunction
ECM malfunction
NOTE:
When DTC P0105 (No.11), P0110 (No.18), P0115 (No.19) and P0120 (No.13) are indicated together, it
is possible that “ORN” circuit is open.
Before inspecting, be sure to check that ambient temperature is higher than – 40°C (– 40°F).
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Check IAT Sensor and Its Circuit.
1) Connect scan tool to DLC with ignition
switch OFF.
2) Turn ignition switch ON.
3) Check intake air temp. displayed on scan
tool. See Fig. 1.
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” in
Section 0A.

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-57
Fig. 3 for Step 4
DTC P0115 (DTC NO.19) ENGINE COOLANT TEMPERATURE (ECT) CIRCUIT
MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
C42-14
5V
ECM
LT GRN
ORN
YEL/GRN
C42-10
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
DTC DETECTING CONDITION POSSIBLE CAUSE
Low engine coolant temperature (High voltage-High resis-
tance)
or
High engine coolant temperature (Low voltage-Low resis-
tance)“LT GRN” circuit open or shorted to power
“ORN” circuit open
ECT sensor malfunction
ECM malfunction
NOTE:
Before inspecting, be sure to check that coolant temp. meter in combination meter indicates normal
operating temperature (Engine is not overheating).
When this DTC and P1709 are stored together, also clear DTC stored in TCM after completion of
repair.
When DTC P0105 (No.11), P0110 (No.18), P0115 (No.19) and P0120 (No.13) are indicated together, it
is possible that “ORN” circuit open.