Toyota Celica 2005 Repair Manual page 591

DI−392
CIRCUIT DESCRIPTION
HINT:
This Electrical Throttle Control System (ETCS) does not use a throttle cable.
S
This throttle position sensor is a non−contact type.
S
The throttle position sensor is mounted on the throttle body. It detects the opening angle of the throttle valve.
This sensor is electronically controlled and uses Hall−effect elements, so that accurate control and reliability
can be obtained. The throttle position sensor has 2 sensor elements/signal outputs: VTA1 and VTA2. VTA1
is used to detect the throttle opening angle and VTA2 is used to detect malfunctions in VTA1. Voltage applied
to VTA1 and VTA2 changes between 0 V and 5 V depending on the opening angle of the throttle valve. This
sensor includes 2 signals, VTA1 and VTA2. VTA1 is used to detect the throttle opening angle and VTA2 is
used to detect malfunctions in VTA1. There are several checks that the ECM performs to confirm proper
operation of the throttle position sensor and VTA1.
The ECM judges the current opening angle of the throttle valve from these signals input from terminals VTA1
and VTA2, and the ECM controls the throttle motor to make the throttle valve angle properly in response to
driver inputs.
Throttle Position Sensor
Magnet
IC No. 1
IC No. 2
Magnet
A19755
2005 CELICA (RM1131U)
DIAGNOSTICS
ECM
VC
VTA1
VTA2
E2
− ENGINE (2ZZ−GE)
Fail Safe Angle
1
*
5
2.60
2.25
0.97
0.69
7
0
Throttle Valve Opening Angle (deg)
Throttle Valve Fully Closed
(Throttle opening position expressed as percentage
(VAT1) 0 to 20 %)
Throttle Valve Fully Opened
(Throttle opening position expressed as percentage
(VAT1) 64 to 96 %)
1
: Fail Safe Angle 7°
*
(Throttle opening position expressed as percentage
(VAT1) 8 to 20 %)
590
Usable Range
86
A19802