Toyota COROLLA2004, Электрическая схема проводки

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2004 COROLLA (EWD533U)
156
ABS
ABS is a brake system designed to improve the operating ability and securing the stability of the vehicle by preventing the
lock–up of the vehicle by controlling the wheel cylinder pressure of all the four wheels at the time of sudden braking.
1. Input Signals
(1) Speed sensor signal
The speed of the wheels is detected and input to TERMINALS FL+, FR+, RL+, and RR+ of the skid control ECU and
actuator.
(2) Stop light SW signal
A signal is input to TERMINAL STP of the skid control ECU with actuator when brake pedal is depressed.
2. System Operation
When the wheels are locked–up, the solenoid inside the actuator is controlled by the signal from the skid control ECU with
actuator, and the brake fluid in the wheel cylinder will flow through the reservoir and reduce the hydraulic pressure.
While the ABS is in operation, as the skid control ECU with actuator always outputs the operation signal to the pump inside
the actuator, and the brake fluid stored inside the reservoir will be sucked up by the pump inside the actuator and returned to
the master cylinder.
When the hydraulic pressure of the wheel cylinder is decompressed or increased until the necessary hydraulic pressure, the
solenoid inside the actuator is controlled by the control signal from the skid control ECU with actuator and as a result,
hydraulic pressure of the wheel cylinder will be closed at both the master cylinder and reservoir sides routes, and the
hydraulic pressure of the wheel cylinder will be in the hold condition.
If increase of the hydraulic pressure volume of the wheel cylinder becomes necessary, the control signals from the skid
control ECU with actuator control the solenoid inside the actuator, to resume to the normal condition. Thus the brake fluid of
the master cylinder will be sent to the wheel cylinder and will increase the hydraulic pressure of the wheel cylinder. At this
time, in the case that the brake fluid is left in the reservoir, it will be sucked up by the pump inside the actuator and will be
sent to the wheel cylinder.
A3, A4 ABS Speed Sensor Front LH, RH
2–1 : 0.92 –1.22 k
Ω
(25
°C,
77
°F)
A19, A20 ABS Speed Sensor Rear LH, RH
1–2 : 1.0 –1.4 k
Ω (
25
°
C, 77
°
F)
S1 Skid Control ECU with Actuator
23, 1–Ground : Always continuity
3–Ground : Approx. 12 volts with the ignition SW at ON position
16–Ground : Approx. 12 volts with the brake pedal depressed
2, 24–Ground : Always approx. 12 volts
: Parts Location
Code See Page Code See Page Code See Page
A3 32 C9 34 P3 35
A4 32 D1 34 S1 33
A19 36 D2 34 S9 35
A20 36 I10 35
B2 32 J6 35
: Relay Blocks
Code See Page Relay Blocks (Relay Block Location)
1 22 Engine Room R/B (Engine Compartment Left)
System Outline
Service Hints