Suzuki 2000 Grand Vitara SQ416, Service Manual

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YH4
GRAND
VITARA
ENGINE (H25 ENGINE) 6-1-53
Fig. for STEP 2
DTC CONFIRMATION PROCEDURE
NOTE:
Check to make sure that following conditions are satisfied when using this DTC CONFIRMATION PROCE-
DURE.
WARNING:
D
When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and very careful during to avoid occurrence of an accident.
D
Road test, should be carried out with 2 person, a driver and tester, on a level road.
D
Intake air temperature: between – 14
_
C and 70
_
C (6.8
_
F and 158
_
F)
D
Atmospheric pressure: higher than 560 mmHg (Altitude: lower than 2790 m (9150 ft))
(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.
DTC TROUBLESHOOTING
STEP ACTION YES NO
1 Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE
DIAG. FLOW
TABLE”.
2 MAF Sensor Power Supply Voltage check:
(1) With ignition switch OFF, disconnect MAF sensor
coupler (1).
(2) With ignition switch ON, check voltage between
C32-3 (2) and ground.
Is voltage 10 – 14 V?
Go to Step 3. Faulty “Bl / B” wire.
3 MAF Sensor Output Voltage check:
(1) With ignition switch OFF, connect MAF sensor
coupler.
(2) Remove ECM (PCM) cover.
(3) With ignition switch ON leaving engine OFF, check
voltage between C51-3-23 and C51-3-21 terminal.
Is voltage 0.5 – 1.0 V?
Poor C51-3-23 or /
and C51-3- 21
terminal connection.
If OK, substitute a
known-good ECM
(PCM) and recheck.
Faulty “V / W” wire
and “Gr / Y” wire.
Poor C32 coupler
terminal connection.
If wire and
connection are OK,
substitute a known-
good MAF sensor
and recheck.