2001 SUZUKI GRAND VITARA temperature sensor

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

6-1-50 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0110 (DTC No.23, 25) Intake Air Temp. (IAT) Circuit Malfunction
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and run
engine at idle speed and engine coolant temp. 110°C (230°F) or lower for 10 sec. or more.
3) Check DTC by using scan tool.
1. IAT sensor
2. ECM (PCM)
DTC DETECTING CONDITION TROUBLE AREA
Any one of the conditions are detected for 5 sec. con-
tinuously.
• Low intake air temperature (high voltage-high resis-
tance)
• High intake air temperature (Low voltage-low resis-
tance)• IAT sensor circuit
• IAT sensor
• ECM (PCM) malfunction

6-1-52 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0115 (DTC No.14, 15) Engine Coolant Temp. Circuit Malfunction
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and run
engine at idle speed for 10 sec. or more.
3) Check DTC by using scan tool.
1. ECT sensor
2. To combination (ECT) meter
3. ECM (PCM)
DTC DETECTING CONDITION TROUBLE AREA
Any one of the conditions are detected for 5 sec. continu-
ously.
• Low engine coolant temperature (high voltage-high
resistance)
• High engine coolant temperature (low voltage-low
resistance)ECT sensor circuit
ECT sensor
ECM (PCM)
NOTE:
Check to make sure that following conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
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)

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-59
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and start
engine.
3) Increase vehicle speed to 55 km/h (35 mph) or more.
4) Keep driving above vehicle speed for 2 min. or more (Change of vehicle speed is permitted in this step).
5) Stop vehicle, and run engine at idle speed for 1 min.
6) Check if pending DTC exists by using scan tool. If not, check if oxygen sensor monitoring test has completed
by using scan tool. If not in both of above checks (i.e., no pending DTC and oxygen sensor monitoring test
not completed), check vehicle condition (environmental) and repeat step 3) through 6).
TROUBLESHOOTING
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 conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
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)
Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE
DIAG. FLOW
TABLE” in this sec-
tion.
2 HO2S-1 output voltage check :
1) Connect scan tool to DLC with ignition switch OFF.
2) Warm up engine to normal operating temperature and
keep it at 2000 r/min. for 60 sec.
3) Repeat racing engine (Repeat depressing accelerator
pedal 5 to 6 times continuously to enrich A/F mixture
and take foot off from pedal to enlean and check HO2S
output voltage displayed on scan tool. See Fig.
Is over 0.6 V and below 0.3 V indicated?Go to Step 4. Go to Step 3.
3 HO2S-1 check :
1) With ignition switch OFF, disconnect HO2S-1 connec-
tor.
2) Check for proper connection to HO2S-1 at each termi-
nal.
3) If OK, connect voltmeter “1” and “2” terminal of HO2S-1
connector.
4) Start engine and check voltmeter while repeating rac-
ing engine.
Is over 0.6 V and below 0.3 V indicated?“RED” or “GRY/
YEL” circuit open or
short.
If wire and connec-
tions are OK, sub-
stitute a known-
good ECM (PCM)
and recheck.Replace HO2S-1.

6-1-68 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and start
engine.
3) Increase vehicle speed to 55 km/h (35 mph) or more.
4) Keep driving above vehicle speed for 2 min. or more (Change of vehicle speed is permitted in this step).
5) Stop vehicle, and run engine at idle speed for 1 min.
6) Check if pending DTC exists by using scan tool. If not, check if oxygen sensor monitoring test has completed
by using scan tool. If not in both of above checks (i.e., no pending DTC and oxygen sensor monitoring test
not completed), check vehicle condition (environmental) and repeat step 3) through 6).
TROUBLESHOOTING
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 conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
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)
Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE
DIAG. FLOW
TABLE” in this sec-
tion.
2 HO2S-1 output voltage check :
1) Connect scan tool to DLC with ignition switch OFF.
2) Warm up engine to normal operating temperature and
keep it at 2000 r/min. for 60 sec.
3) Repeat racing engine (Repeat depressing accelerator
pedal 5 to 6 times continuously to enrich A/F mixture
and take foot off from pedal to enlean and check HO2S
output voltage displayed on scan tool. See Fig.
Is over 0.6 V and below 0.3 V indicated?Go to Step 4. Go to Step 3.
3 HO2S-1 check :
1) With ignition switch OFF, disconnect HO2S-1 connec-
tor.
2) Check for proper connection to HO2S-1 at each termi-
nal.
3) If OK, connect voltmeter “1” and “2” terminal of HO2S-1
connector.
4) Start engine and check voltmeter while repeating rac-
ing engine.
Is over 0.6 V and below 0.3 V indicated?“RED/BLU” or
“GRY/YEL” circuit
open or short.
If wire and connec-
tions are OK, sub-
stitute a known-
good ECM (PCM)
and recheck.Replace HO2S-1.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-113
DTC P1450/P1451 Barometric Pressure Sensor Circuit Malfunction/Perfor-
mance Problem
SYSTEM DESCRIPTION
Barometric pressure sensor is installed in ECM (PCM).
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
For DTC P1450
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC by using scan tool and run engine for 1 min.
3) Check DTC by using scan tool.
For DTC P1451
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and warm up
engine to normal operating temperature.
3) Increase engine speed to 3,000 r/min. in 3rd gear in case of M/T and “2” range in case of A/T.
4) Release accelerator pedal and with engine brake applied, keep vehicle coasting for 5 sec. or more (keep fuel
cut condition for 5 sec. or more). If fuel cut condition is not kept for 5 sec. or more, coast down a slope in
engine speed 1600 – 3000 r/min for 5 sec. or more.
5) Stop vehicle and run engine at idle.
6) Repeat steps 3) – 5) 2 times.
7) Check pending DTC by using scan tool.
TROUBLESHOOTING (DTC P1450/P1451)
DTC DETECTING CONDITION TROUBLE AREA
DTC P1450 :
Barometric pressure out of specification is detected.•Barometric pressure sensor in ECM
(PCM)
DTC P1451 :
While running under conditions described for “DTC CONFIRMATION
PROCEDURE”, barometric pressure value compared with intake
manifold vacuum value in fuel cut state is not as specified.
(2 driving cycle detection logic)•Manifold absolute pressure sensor
performance problem
•Barometric pressure sensor in 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.
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE DIAG. FLOW
TABLE” in this section.
2 Is DTC P1451 set? Go to Step 3. Substitute a known-good
ECM (PCM) and recheck.
3 MAP sensor check :
1) Check MAP sensor and its circuit referring to
Steps 2 and 3 of “DTC P1408 Diag. Flow Table”.
Is check result satisfactory?Substitute a
known-good
ECM (PCM) and
recheck.MAP sensor or its circuit mal-
function.

ENGINE MECHANICAL (H27 ENGINE) 6A2-27
12) Disconnect the following electric lead wires :
•Injector wire coupler
•CMP sensor coupler
•Ignition coil couplers
•CKP sensor coupler
•MAP sensor coupler
•TP sensor (1) coupler
•IAC valve (2) coupler
•Earth wire (3) from surge tank
•EVAP canister purge valve coupler
•EGR valve coupler
•Oxygen sensor -1 and -2 couplers referring to “Exhaust Man-
ifold” in this section
•Coolant temperature sensor coupler
•Knock sensor coupler
•Generator wires
•Starter wires
•Oil pressure wire
•P/S pump wire
•Earth wire from generator bracket
•Engine block heater (if equipped)
13) Remove clamps and brackets.
14) Disconnect the following hoses :
•Heater hose from heater water pipe
•Heater hose from water outlet cap
•EVAP canister hose from canister pipe
•Brake booster vacuum hose
15) Remove EVAP canister purge valve (5).
16) Disconnect the following hoses at the location shown in the
figure :
•Fuel feed hose (1) from fuel feed pipe
•Fuel return hose from (2) fuel return pipe
17) Remove P/S pump assembly. Refer to “POWER STEERING
PUMP” in Section 3B1.
18) Remove A/C compressor assembly. Refer to “COMPRES-
SOR ASSEMBLY” in Section 1B.
19) Remove steering shaft lower assembly. Refer to “STEERING
LOWER SHAFT ASSEMBLY” in Section 3C1.
20) Raise vehicle.
21) Remove front differential housing with differential from chas-
sis if equipped. Refer to “DISMOUNTING” in Section 7E.
22) Remove exhaust No.1 pipe. Refer to “EXHAUST MANI-
FOLD” in this section.
23) Remove exhaust manifold stiffener from transmission.
4. Clamp bracket
6. EGR valve
7. Heater hose
2
14
3
75
6

6E2-2 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Fuel injector.......................................... 6E2-26
Electronic Control System........................ 6E2-31
Engine control module (ECM)/
powertrain control module (PCM) ........ 6E2-31
Mass air flow sensor (MAF sensor)...... 6E2-32
Intake air temperature (IAT) sensor ..... 6E2-34
Throttle position sensor (TP sensor) .... 6E2-35
Engine coolant temperature sensor
(ECT sensor) ........................................ 6E2-36
Heated oxygen sensor (sensor 1) ........ 6E2-37
Heated oxygen sensor (sensor 2) ........ 6E2-38
Vehicle speed sensor (VSS) ................ 6E2-39
Manifold absolute pressure sensor ...... 6E2-39
Fuel level sensor (sender gauge)......... 6E2-41
Crankshaft position sensor................... 6E2-41Main relay ............................................ 6E2-41
Fuel pump relay ................................... 6E2-42
Fuel cut operation ................................ 6E2-43
Emission Control System......................... 6E2-44
EGR system (if equipped) .................... 6E2-44
EVAP canister ...................................... 6E2-45
Vacuum passage ................................. 6E2-46
PCV System ............................................ 6E2-47
PCV hose ............................................. 6E2-47
PCV valve ............................................ 6E2-47
PCV system ......................................... 6E2-48
Tightening Torque Specification.............. 6E2-48
Special Tool ............................................... 6E2-48

General Description
The engine and emission control system has 4 major sub-systems: air intake system, fuel delivery system, elec-
tronic control system and emission control system.
Air intake system includes air cleaner, mass air flow sensor, throttle body, idle air control valve and intake man-
ifold.
Fuel delivery system includes fuel pump, delivery pipe, fuel pressure regulator, fuel injectors, etc.
Electronic control system includes ECM (PCM), various sensors and controlled devices.
Emission control system includes EGR, EVAP and PCV systems.