Mass Air Flow (Maf) And Intake Air Temperature (Iat) Sensor On-Vehicle Inspection; Mass Air Flow (Maf) And Intake Air Temperature (Iat) Sensor Removal And Installation - Suzuki GRAND VITARA Owner's Manual

1C-13 Engine Electrical Devices:
Mass Air Flow (MAF) and Intake Air
Temperature (IAT) Sensor On-Vehicle
Inspection
NOTE
Before performed this inspection, be sure to
read the "Precautions of ECM Circuit
Inspection: in Section 1A".
1) Disconnect MAF and IAT sensor connector.
2) Connect voltmeter to "BLU/BLK" wire terminal (2) of
MAF and IAT sensor connector (1) disconnected and
ground.
3) Turn ON ignition switch and check that voltage is
battery voltage.
If not, check if wire harness is open or connection is
poor.
4) Turn OFF ignition switch and connect connector to
MAF and IAT sensor.
5) Connect special tool between ECM and ECM
connector referring to "Inspection of ECM and Its
Circuits: in Section 1A"
6) Turn ON ignition switch and check MAF signal
voltage between "C37-26" terminal circuit and "C37-
27" terminal circuit of special tool.
MAF signal voltage between "C37-26" terminal
circuit and "C37-27" terminal circuit of special
tool
MAF signal voltage of MAF and IAT sensor with
ignition switch turned ON: 0.5 – 1.0 V
"C37-27"
1. ECM
S5JB0A1306019
I3RB0A130009-01
"C37-26"
1
I4RS0A130009-01
7) Start engine and check that voltage is lower than 5 V
and it rises as engine speed increases.
MAF signal voltage between "C37-26" terminal
circuit and "C37-27" terminal circuit of special
tool
MAF signal reference voltage of MAF and IAT
sensor at specified Idle speed: 1.3 – 1.8 V
8) If check result is not as specified above, cause may
lie in wire harness, connector connection, MAF and
IAT sensor or ECM.
Mass Air Flow (MAF) and Intake Air
Temperature (IAT) Sensor Removal and
Installation
CAUTION
!
• Do not disassemble MAF and IAT sensor.
• Do not expose MAF and IAT sensor to any
shock.
• Do not clean MAF and IAT sensor.
• If MAF and IAT sensor has been dropped, it
should be replaced.
• Do not blow compressed air by using air
gun or the like.
• Do not put finger or any other object into
MAF and IAT sensor. Malfunction may
occur.
Removal
1) Disconnect negative cable at battery.
2) Disconnect MAF and IAT sensor connector.
3) Remove MAF and IAT sensor (1) from air cleaner
case.
S5JB0A1306020
1
I5JB0A130033-02