Toyota Land Cruiser 100 / Amazon, Lexus LX 470

Since 1997 of release

Repair and car operation

System of antiblocking of brakes (ABS) – the general information and codes of malfunctions

The general information

The typical scheme of an arrangement of components ABS

The electronic block of management (ECU) ABS

ECU systems ABS it is fixed under a forward overlay of a threshold of the right door.

ECU traces speed of rotation of each of car wheels, being guided by arriving signals from wheel gauges. When at emergency braking any of wheels it starts to be blocked prematurely, ECU gives out a command on activation of the electromagnetic valve placed in the hydraulic modulator which, working, opens a corresponding site of a brake contour, letting out from it a part of a working liquid in the tank and, accordingly, reducing working pressure. As soon as speeds of rotation of wheels are equalised, the valve is closed again also pressure continues to rise. The cycle lasts fractions of a second on each of wheels and repeats until braking will not be finished. The system design allows to correct pressure in hydraulic contours of each of four wheels. Actually the scheme of functioning ABS is much more difficult, than it can seem, therefore composers of the present Management do not recommend to owners of cars to make attempt of independent performance of repair of system. In case of occurrence of malfunctions it will be most reasonable to address to experts of car-care centre.

The hydraulic modulator

The modulator is established in an impellent compartment and equipped working at the command of ECU by the electromagnetic valve of adjustment of hydraulic pressure in contours of brake system.

Wheel gauges

Each of wheels is equipped by the individual gauge of turns. The gauge consists of a rotor (a ring with teeth in regular intervals located on its perimetre) and a sensitive element in a kind подмагниченной coils. The sensitive element of the gauge fixes the moments of passage by it teeths of a rotor and will transform the received information to the electric signals continuously transferred to the module of management ABS. By results of processing of arriving signals ECU receives the information on relative speed of rotation of each of wheels. While all four wheels rotate with identical frequency, ABS stays in a passive condition. As soon as any of wheels starts to be blocked, the management block fixes change of an entering signal and develops a command on operation of the modulator instantly dumping pressure of a hydraulic liquid in the brake mechanism of the corresponding wheel.

The gauge-switch of stoplights

On the signals arriving from the gauge-switch of stoplights ECU defines the moment when the driver squeezes out a pedal of a foot brake, at once activating ABS.

Diagnostics and regenerative repair

If built in in the panel of devices of the car control lamp ABS lights up and continues to burn during movement, first of all make sure that the lay brake is completely released, and the brake system functions regularly. If all in norm, hence, was refusal ABS. Thus in memory ECU the malfunction code should be brought. At diagnostics and reading of codes of malfunctions the warning bulb on the panel of devices will blink. In the presence of several codes, their indication will be begun with smaller number on increasing, without dependence from time of their receipt. At movement of the car malfunction codes are not displayed. Spend visual survey:

1. Check up a condition of brake supports and wheel cylinders;
2. Check up a condition and reliability of fastening contact р
3. азъемов electroconductings ECU and wheel gauges (the Onboard electric equipment see);
4. Check up corresponding safety locks (the Onboard electric equipment see).

Regenerative repair ABS falls outside the limits qualification of the average mechanic-fan.

Reading and deleting of codes of malfunctions