Suzuki Grand Vitara JB627. Manual - part 40
1A-109 Engine General Information and Diagnosis:
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 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”.
• Intake air temperature: –10
°C (14 °F) to 80 °C (176 °F).
• Engine coolant temperature: 30
°C (86 °F) or more.
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more).
• The following DTC is not detected: ECT sensor, CKP sensor, IAT sensor, MAP sensor, A/F sensor, A/
F sensor heater, TP sensor, barometric pressure sensor, MAF sensor, EGR system and CMP sensor.
1) With ignition switch 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.
4) Drive vehicle at 40 mph (60 km/h) or higher. (engine speed: 2500 – 3000 r/min.)
5) Keep above vehicle speed for 4 min. or more. (Throttle valve opening is kept constant in this step.)
6) Check if DTC and pending DTC exist by using scan tool. If not, check if oxygen sensor monitoring test has been
completed by using scan tool. If not in both of above checks (i.e., no DTC and pending DTC and oxygen sensor
monitoring test not completed), check vehicle condition (environmental) and repeat Step 3) through 6).
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
Intake system and exhaust system for leakage check
1) Check intake system and exhaust system for leakage.
Are intake system and exhaust system in good condition?
Go to Step 3.
Repair or replace
defective parts.
3
Fuel pressure check
1) Check fuel pressure referring to “Fuel Pressure Check”.
Is check result satisfactory?
Go to Step 4.
Repair or replace
defective parts.
4
Fuel injectors and its circuit check
1) Check fuel injectors referring to “Fuel Injector Inspection
Is check result satisfactory?
Go to Step 5.
Faulty injector(s) or its
circuit.
5
MAF sensor visual inspection
1) Check MAF sensor and air intake system.
• Objects which block measuring duct and resistor of
MAF sensor.
• Other air flow which does not pass MAF sensor.
Are they in good condition?
Go to Step 6.
Repair or replace
defective part.