YH4
GRAND
VITARA
6-1-60 ENGINE (H25 ENGINE)
DTC P0121 THROTTLE POSITION CIRCUIT PERFORMANCE PROBLEM
WIRING DIAGRAM
Refer to DTC P0120 (DTC No.21, 22).
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITION TROUBLE AREA
Throttle opening is detected as small (rationality-low) while
engine is running under high road and high speed conditions
or as large (rationality-high) while engine is running under low
load and low speed conditions.
Air intake system
TP sensor
TP sensor circuit
ECM (PCM)
DTC CONFIRMATION PROCEDURE
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.
NOTE:
Check to make sure that following conditions are satisfied when using this DTC CONFIRMATION PROCE-
DURE.
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 warm up to normal operating temperature.
(4)Increase vehicle till engine speed is reach ed 3300 – 3700 r/min. for 10 sec.
(5)Stop vehicle and run engine at idle speed for 10 sec.
(6)Check DTC and pending DTC by using scan tool.