Suzuki Engine 2002 GRAND VITARA SQ625, Service Manual

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ENGINE GENERAL INFORMATION AND DIAGNOSIS (G16/J20 ENGINES) 6-69
DTC P0121 Throttle Position Range/Performance Problem
WIRING DIAGRAM
Refer to DTC P0120.
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and start
engine.
3) Increase vehicle speed to 60 km/h (40 mph).
4) Keep driving above vehicle speed for 5 min. (Change of vehicle speed is permitted in this step).
5) Stop vehicle and run engine at idle speed for 1 min.
6) Increase vehicle speed till engine speed is reached 2,000 – 3,000 r/min in proper gear.
7) Keep driving at that engine speed for 30 sec. or more (Engine speed is kept constant in this step).
8) Stop vehicle.
9) Repeat Step 6) to 8).
10) Check DTC and pending DTC by using scan tool.
DTC DETECTING CONDITION TROUBLE AREA
Throttle opening change is smaller than specification while
intake air volume changes and engine is
running at constant speed.
(2 driving cycles detection logic) • TP sensor
• ECM (PCM)
• High resistance in circuit
WARNING:
• When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
• Road test should be carried out with 2 persons, a driver and a tester, on a level road.
NOTE:
Check to make sure that the following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Intake air temp. : –8°C, 18°F or higher
• Engine coolant temp. : –8 – 110°C (18 – 230°F)
• Altitude barometric pressure : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)