Toyota COMPUTER-CONTROLLED SYSTEM

ELECTRONIC CONTROL SYSTEM - A/C Signal, Electrical Load Signa
l
A/C (AIR CONDITIONER)
SIGNA L
This signal senses when the air conditioner
magnetic clutch is on or air conditioner switch is on .
This signal is used to control the ignition timing
during idling, and to control the ISC system, the
fuel cut-off speed, and other functions .
ELECTRICAL CIRCUITRY
Engine ECU
ELECTRICAL LOAD SIGNAL
1 *
This signal detects when the head lamps, rear
window defogger, etc ., are on .
Depending on the vehicle model, the circuitry for
this signal can have a number of electrical load
signals which are brought together and input
into the Engine ECU as a single signal,
as shown
in the following electrical circuit, or it can have
each signal input to the Engine ECU separately .
This signal is used for control of the ISC system
.
ELECTRICAL CIRCUITR
Y
A/C
magnetic
clutch
C
OHP 3 4
A/C
amplifie r
A/C
switch
0
A/C
Engine ECU
Engine EC U
OHP 34
39