Suzuki Grand Vitara JB627. Manual — part 33

1A-81 Engine General Information and Diagnosis:

DTC P0111: Intake Air Temperature Sensor Circuit Performance

S6JB0B1104021

Wiring Diagram

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

WARNING

!

• When performing a road test, select a place where there is no traffic or possibility of a traffic

accident and 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 the following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Atmospheric pressure: higher than 75 kPa (560 mmHg) (Altitude: lower than 2790 m (9150 ft)).
• Engine coolant temperature at engine start: between –10

°C and 30 °C (14 °F and 86 °F).

• The following DTCs are not detected: MAF sensor, ECT sensor and IAT sensor (other than P0111).

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E23

C37

5V

GRY/GRN

GRY/GRN

BLU/BLK

BLU

RED

C37-23

C37-24

C37-67

C37-4

LT GRN

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G

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S

I6JB01110030-03

S: IAT sensor signal circuit

1. MAF and IAT sensor

3. To other sensors

G: IAT sensor ground circuit

2. ECM

4. From main relay

DTC detecting condition

Trouble area

Variation of IAT sensor signal is less than 15 mV even through ECT
reaches 75

°C after engine is started with ECT less than 30 °C.

(2 driving cycle detection logic)

• IAT sensor and its circuit
• ECM

Engine General Information and Diagnosis: 1A-82

1) With ignition switch OFF, connect scan tool.
2) Turn ON ignition switch, clear DTC if any.
3) Start engine and warm up to normal operating temperature.
4) Drive vehicle more than 37 mph (60 km/h) for 15 min.
5) Stop vehicle and run engine at idle speed for 1 min.
6) Check DTC and pending DTC by using scan tool.

DTC Troubleshooting

NOTE
Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to
“Precautions for DTC Troubleshooting”.

DTC P0112 / P0113: Intake Air Temperature Sensor Circuit Low / High Input

S6JB0B1104022

Wiring Diagram
Refer to “DTC P0111: Intake Air Temperature Sensor Circuit Performance”.

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

1) With ignition switch OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC by using scan tool if any.
3) Start engine and run it for 10 sec.
4) Check DTC by using scan tool.

Step

Action

Yes

No

1

Was “Engine and Emission Control System Check”
performed?

Go to Step 2.

Go to “Engine and
Emission Control
System Check”.

2

IAT sensor check
1) Check IAT sensor for performance referring to “Mass Air

Flow (MAF) and Intake Air Temperature (IAT) Sensor
On-Vehicle Inspection in Section 1C”.

Is it in good condition?

Go to Step 3.

Replace MAF and IAT
sensor.

3

Wire harness check
1) Check signal and ground circuits of IAT sensor for

condition referring to Step 2 and 3 of “DTC P0112 /
P0113: Intake Air Temperature Sensor Circuit Low / High
Input”.

Are they in good condition?

Substitute a known
good ECM and recheck.

Repair or replace.

DTC detecting condition

Trouble area

P0112: Intake Air Temperature Sensor Circuit Low Input
Circuit voltage of IAT sensor is less than 0.16 V for 5 seconds or longer.
(1 driving cycle detection logic)

• IAT sensor and its circuit
• ECM

P0113: Intake Air Temperature Sensor Circuit High Input
Circuit voltage of IAT sensor is more than 5.0 V for 5 seconds or longer.
(1 driving cycle detection logic)

1A-83 Engine General Information and Diagnosis:

DTC Troubleshooting

NOTE
Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to
“Precautions for DTC Troubleshooting”.

Step

Action

Yes

No

1

Was “Engine and Emission Control System Check”
performed?

Go to Step 2.

Go to “Engine and
Emission Control
System Check”.

2

Wire harness check
1) Turn ignition switch OFF position.
2) Disconnect connectors from IAT sensor and ECM.
3) Check for proper terminal connection to IAT sensor and

ECM connectors.

4) If connections are OK, check that IAT sensor circuit is as

follows.
• Wiring harness resistance of each IAT sensor signal

and ground circuit is less than 3

Ω.

• Insulation resistance of IAT sensor signal circuit is

infinity between IAT sensor connector and vehicle
body ground.

• Insulation resistance of wire harness is infinity

between IAT sensor signal terminal and each other
terminal at MAF and IAT sensor connector.

• Circuit voltage of each IAT sensor signal and ground

circuit is 0 – 1 V with ignition switch turned ON.

Are they in good condition?

Go to Step 3.

Repair or replace
defective wire harness.

3

IAT sensor reference voltage check
1) Connect connectors to ECM.
2) Turn ignition switch to ON position.
3) Check that IAT sensor signal voltage is 5 V between IAT

sensor connector and vehicle body ground.

Is it in good condition?

Go to Step 4.

Substitute a known
good ECM and recheck.

4

IAT sensor check
1) Check IAT sensor for performance referring to “Mass Air

Flow (MAF) and Intake Air Temperature (IAT) Sensor
On-Vehicle Inspection in Section 1C”.

Is it in good condition?

Substitute a known
good ECM and recheck.

Replace MAF and IAT
sensor.

Engine General Information and Diagnosis: 1A-84

DTC P0116: Engine Coolant Temperature Circuit Range / Performance

S6JB0B1104023

Wiring Diagram

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

NOTE
Check to make sure that the following conditions are satisfied when using this “DTC Confirmation
Procedure”.
The following DTCs are not detected: MAF sensor, IAT sensor, VSS and ECT sensor (other than DTC
P0116)

1) With ignition switch OFF, connect scan tool.
2) Turn ON ignition switch, clear DTC if any.
3) Drive vehicle more than 37 mph (60 km/h) for more than 10 minutes.
4) Stop vehicle.
5) Check DTC and pending DTC by using scan tool.

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E23

C37

C37-67

GRY/GRN

GRY/GRN

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2

5V

C37-26

PPL/YEL

S

G

I6JB01110031-02

S: ECT sensor signal circuit

1. ECT sensor

3. To other sensors

G: ECT sensor ground circuit

2. ECM

DTC detecting condition

Trouble area

• Variation of ECT sensor input voltage is 15 mV or less even though

vehicle has been driven for 10 min or more after starting engine.

(2 driving cycle detection logic, monitoring once per driving cycle)

• ECT sensor and its circuit
• Thermostat
• ECM