Suzuki Engine 2002 GRAND VITARA SQ420 Service Manual page 272

• Intake air temperature : between 5°C and 70°C (6.8°F and 158°F)
• 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 warm up to normal operating temperature.
4) Increase vehicle speed to 56 km/h (35 mph) for 30 sec.
5) Stop vehicle and run engine at idle speed for 10 sec.
6) Check DTC and pending DTC by using scan tool.
DTC TROUBLESHOOTING
Step
1 Was "Engine Diag. Flow Table" performed?
2 MAP Sensor Signal check :
1) Remove ECM (PCM) cover.
2) Check voltage between C51-3-13 and C51-
3-21 as following conditions. with ignition
switch on
leaving engine OFF : 3.3 – 4.3 V
idling : less than 3.3 V
Is check result as specified?
3 MAP Sensor Power Supply Voltage check :
1) With ignition switch OFF, disconnect coupler
from MAP sensor.
2) Check voltage between "GRY/RED" wire
terminal and "GRY/YEL" wire terminal.
Is voltage 4.5 – 5.5 V?
Fig. for Step 3
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H25 ENGINE) 6-1-131
Action Yes
Go to Step 2.
Intermittent trouble.
If OK, substitute a known-
good ECM (PCM) and
recheck.
Faulty "RED/WHT" wire.
If OK, substitute a known-
good MAP sensor and
recheck.
No
Go to "Engine Diag. Flow
Table".
Go to Step 3.
Faulty "GRY/RED", "GRY/
YEL" wire.
If OK, substitute a known-
good ECM (PCM) and
recheck.