Toyota COMPUTER-CONTROLLED SYSTEM User Manual

ELECTRONIC CONTROL SYSTEM
- Stop Lamp Switch, Oil Pressure Switch,
Communications Signal s
STOP LAMP SWITC H
This signal is used to detect when the brakes
have been applied
. The STP signal voltage is the
same as the voltage supplied to the stop lamps,
as seen in the diagram below .
The STP signal is used mainly to control the fuel
cut-off engine speed
. (The fuel cut-off engine
speed is reduced slightly when the vehicle is
braking . )
ELECTRICAL CIRCUITR Y
~Stop lamp
switch
STP or BR K
Lamp
failure ;
relay'
- -
Engine EC U
Stop lamps
L _____ J
* Some vehicle models only
OHP 3 9
OIL PRESSURE SWITC H
This signal is used to judge whether the engine
oil pressure is low or high . The oil pressure
signal is used mainly in controlling the ISC
system .
ELECTRICAL CIRCUITRY
COMMUNICATIONS SIGNALS
©
Communications signals are signals that are sent
between different
ECUs to make it possible for
them to coordinate their operations .
These communications signals are explained
below .
1 . THROTTLE OPENING ANGLE SIGNAL S
The throttle opening angle (VTA) signal from the
throttle position sensor is processed by the
Engine ECU, then sent to the ECT ECU,
Suspension ECU, etc
., as combinations of the L1,
L2, and L3 signals .
ELECTRICAL CIRCUITR Y
ECT ECU
Engine ECU
OHP 3 9
2
. THROTTLE OPENING ANGLE SIGNALS
FOR TRC (TRACTION CONTROL)
SYSTE M
These signals are the throttle opening angle
(VTA1 and VTA2)
signals which are input from
the main and sub thro tt
le position sensors, then
passed on by the Engine ECU to the TRC ECU .
ELECTRICAL CIRCUITR Y
TRC ECU
Engine EC U
VTH VT H
VSH VSH
01
VTA 1
OHP 39
45

Toyota COMPUTER-CONTROLLED SYSTEM Specifications

General

Brand	Toyota
Model	COMPUTER-CONTROLLED SYSTEM
Category	Automobile Accessories
Language	English