Suzuki 2000 Grand Vitara SQ416, Service Manual

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YH4
GRAND
VITARA
TERMINAL ARRANGEMENT OF ECM (PCM)
COUPLER (VIEWED FROM HARNESS SIDE)
C51-3-20 C51-3-23
6E2-32 ENGINE AND EMISSION CONTROL SYSTEM (H25 ENGINE)
MASS AIR FLOW SENSOR (MAF SENSOR)
Inspection
NOTE:
Use voltmeter with high-impedance (10 k
/ V minimum) or dig-
ital type voltmeter.
1) Remove ECM (PCM) cover from bracket.
2) With ignition switch OFF, disconnect MAF sensor connector (1).
3) Connect voltmeter to C32-3 terminal (2) of MAF sensor connec-
tor disconnected and ground.
4) Turn ignition switch ON and check that voltage is battery volt-
age.
If not, check if wire harness is open or connection is poor.
5) Turn ignition switch OFF and connect MAF sensor connector to
MAF sensor.
6) Turn ignition switch ON and check voltage between C51-3-23
and C51-3-20 terminal.
Standard voltage: 0.5 – 1.0 V
7) Start engine and check that voltage is lower than 5V and it rises
as engine speed increases.
(Reference data:
1.5 – 1.8 V at specified idle speed)
If check result is not as specified above, cause may lie in wire
harness, coupler connection, MAF sensor or ECM (PCM).