Suzuki Grand Vitara 2011 Manual page 150

1A-81 Engine General Information and Diagnosis: For Petrol Engine Model
DTC Troubleshooting
NOTE
Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to
"Precautions for DTC Troubleshooting: For Petrol Engine Model".
Step
1 Was "Engine and Emission Control System Check"
performed?
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?
3 MAF sensor and its circuit check
1) With ignition switch turned OFF, connect scan tool to
DLC.
2) Start engine and warm up to normal operation
temperature.
3) Check MAF value using scan tool. (Refer to "Scan Tool
Data: For Petrol Engine Model" for normal value.)
Is each value within specified range?
4 MAF sensor output voltage check
1) Turn OFF ignition switch.
2) Remove ECM from its bracket with ECM connectors
connected.
3) Measure voltage between "C37-26" and "C37-27"
terminals of ECM connector referring to "Mass Air Flow
(MAF) and Intake Air Temperature (IAT) Sensor On-
Vehicle Inspection: For Petrol Engine Model in Section
1C".
Is each value within specified range?
5 MAF sensor power supply voltage check
1) Disconnect connector from MAF and IAT sensor with
ignition switch turned OFF.
2) Turn ON ignition switch, measure voltage between
engine ground and "BLU/BLK" wire terminal (2) of MAF
and IAT sensor connector (1).
Is voltage 10 – 14 V?
Action
I4RS0A110020-01
Yes
Go to Step 2.
Go to Step 3.
Go to Step 11.
Poor "C37-26" and/or
"C37-27" terminal
connection.
If OK, substitute a
known-good ECM and
recheck.
Go to Step 6.
No
Go to "Engine and
Emission Control
System Check: For
Petrol Engine Model".
Repair or replace.
Go to Step 4.
Go to Step 5.
"BLU/BLK" wire is open
circuit.