6.4.1. General information

In the Corsa-C model in 2004 of release the ABS 8.0 new anti-blocking system in a combination to all options of engines is applied.

The ABS 8.0 system is modular system with 8 electromagnetic valves. It on the main design corresponds to ABS 5.3 system and is in addition got also with system of course stability (ESP).

With introduction of ABS system of 8.0 ESP for the first time in Opel cars at adjustment of brake system the parameter «Temperature of brake system» is considered.

In the hydrounit it is possible to determine by temperature measurement by the characteristic, whether there is a danger of an overheat of brake system at movement under a bias.

The knot of the ABS/control unit of the hydrounit was modified. The weight of knot of the control unit of the ABS / hydrounit was reduced for 25 % thanks to modern microprocessor technology. The external sizes at the same time changed and, therefore, the knot volume for 30 % in comparison with ABS 5.3 system decreased.

The ABS control unit can be removed in the mounted condition from the hydrounit thanks to horizontal assembly situation in the Corsa-C model.

Outwardly the ABS 8.0 system and ABS system of 8.0/ESP differ not only the sizes.

Diameter of hydraulic connections on the ABS control unit from the main brake cylinder in ABS 8.0 system is less, than in ABS system of 8.0/ESP.

Electric connection on the ABS control unit 26-polar in ABS 8.0 system and 46-polar in ABS system of 8.0/ESP.

Depending on ABS 8.0 system option the weight also differs.

The assembly provision of knot of the control unit of ABS/gidroagregat in the Corsa-C model the horizontal. The hydrounit engine with its axis is mounted in horizontal situation, and connections of separate contours of a brake drive specify up. Advantage of such assembly situation consists that at installation or repair work the ABS control unit can be dismantled without removal of all knot.

The ABS 8.0 control unit is based on the latest pulse and microcircuit technology and is calculated on connection of 4 active or 4 passive sensors of a wheel. In the Corsa-C model active sensors of a wheel are used. Function of management and control of ABS 8.0 system has protection via two separate microprocessors 1. These microprocessors will respectively be reprogrammed. Separate components of the ABS control unit are not replaced. At defect it is necessary to replace all ABS control unit.

Management of the pump electric motor in the hydrounit of ABS 8.0 system is made via the pump case. Electromagnetic valves of the hydrounit are put in action via electromagnet coils. These coils are directly connected to the semi-conductor relay in the ABS control unit and thereby built in the ABS control unit.

The ABS control unit is connected to the hydrounit four fixing screws (4), and it can be disconnected from the hydrounit of the car and to remove.

At repair work it is possible to replace components of the ABS control unit and the disconnected hydrounit.

The hydrounit is delivered previously filled in service department. ABS control unit consolidation separately is not on sale. At a leakage between the hydrounit and the ABS control unit it is necessary to replace all knot of the control unit of ABS/gidroagregat in a set.

It is necessary to replace this block with the new block only at uncertain result of diagnostics «Malfunction of the ABS control unit» (at diagnostics by means of Tech 2 and a malfunction code «Defect of the control unit») or in the presence of visible damages on the case or the shtekerny socket of the ABS control unit.

In case the ABS control unit is disconnected from the hydrounit in the mounted condition, it is necessary to pay attention to the maximum purity in an environment zone as the smallest pollution in a zone of valves of the hydrounit can already lead to the wrong functioning.

The ABS control unit cover by no means cannot be pressed. It results in defects invisible outwardly in the control unit (ASG). At installation it is necessary to take the ABS control unit only for external edge of the case and to pay attention to installation without the appendix of efforts.

The ABS control unit by no means cannot be attached to the hydrounit by means of fixing screws. It leads to ABS control unit and/or hydrounit damage.

Replacement of components of ABS 8.0 system, especially in the field of knot of the control unit of ABS/gidroagregat, can be carried out only by the trained personnel with the corresponding special knowledge of terms of replacement and Technologies of maintenance.

As spare parts it is necessary to use only new details specified in the electronic catalog of spare parts.

The hydrounit in the mounted condition is connected to the ABS control unit. At execution with ESP system the sensor of pressure is not established any more outside on the hydrounit as the ABS system has 5.3 TC/ESP, and built in the hydrounit. Separate components of the hydrounit cannot be replaced or repaired. In case of defect, it is necessary to replace respectively the hydrounit in a set or knot of the ABS/control unit of the hydrounit.

Hydraulic connections are located to the main brake cylinder on the hydrounit absolutely differently at ABS 8.0 and ABS systems of 8.0 E. Diameter of hydraulic connections also differs between execution of ABS 8.0 and ABS of 8.0 ESP so installation of erroneous option of the hydrounit is not possible.

The spring contact pins established on a face surface of the ABS control unit, should not concern because of the possible electrostatic category, and it is not necessary to carry out any measurements. Spring contact pins separately are not replaced. In order to avoid damages, a gilded surface of contact pins also by no means it is impossible to process or subject mechanically to processing by liquids, such, such as liquid for processing of electric contact connections.

Also it is impossible to carry out any measurements on plug contacts for the pump engine. Contacts are not replaced and are executed in the lower part of the hydrounit via the klapanny block to the ABS control unit.

In ABS system 8.0 the ESP sensor of pressure is not established any more outside on the hydrounit as the ABS system has 5.3 TC/ESP, and built in the hydrounit. Electric connection to the ABS control unit is made through gilded spring contact pins. The sensor of pressure fastens in the hydrounit with self-fixing 1 and cannot be dismantled. Consolidation is carried out on a conic surface 2.

The temperature sensor is built in addition in the sensor of pressure. The sensor of temperature takes hydrounit temperature. In the ABS control unit these data are used in order that according to characteristics to make the conclusions on loading of brake system. Thus, for example, is defined, whether there is a danger of an overheat of brake system at movement under a bias. Thanks to braking process at movement under a bias disks of the brake mechanism heat up so strongly that being formed warmth is transferred by brake disks through a bracket of the disk wheel brake mechanism to brake liquid. Thus, the temperature in the hydrounit also raises.

The pressure and temperature sensor irrespective of the ABS control unit has the following properties:

self-diagnostics function;

function of complete self-diagnostics with definition of errors of sensitivity and zero shift;

2 analog exits for pressure;

2 digital output for temperature.

Range of measurements of the sensor of pressure: (0–250) bar.

Range of measurements of the sensor of temperature: (–40... +120) °C.

Power supply: 5 In a post. Current.

The pressure sensor separately is not replaced. The contact plate for the pressure sensor in the ABS block, also as spring contacts 1, has a gilded surface. It is not necessary to subject it to machining.

Position of the sensor of pressure cannot be changed (for example, turn). Also it is impossible to load the case of the sensor of pressure mechanically as differently there can be a damage not seen outside. At defect of the sensor of pressure (except a leakage) it is necessary to replace all hydrounit. If in the subsequent at start of system damages on the pressure sensor are fixed, it is necessary to replace the ABS control unit.

At signs of leakage of brake liquid on the sensor of pressure it is necessary to replace knot of the control unit of ABS/gidroagregat in a set as in this case it is impossible to exclude ABS control unit damage by brake liquid more.

Connection on the ABS control unit is executed by Shtekernoye for the ABS 8.0 1 26-polar system and the ABS 8.0 ESP 2 46-polar system. For both options 4 power contacts to one sealing laying on the socket of a plait of wires are provided. Amount of power contacts (2,8 x 0, 8) mm.

For ABS 8.0 system 22 alarm contacts (for ABS system of 8.0 ESP are in addition provided: 42 alarm contacts) with the sizes (0,63 x 0,63) mm. Alarm contacts are protected by silicone consolidation on the ABS control unit socket

The socket of a plait of wires is fixed after putting on by an insert of a plastic bracket.

Look drawing with the hydraulic actuator block diagram – ABS 8.0.

Air removal from a hydraulic actuator of ABS 8.0 system occurs in sequence behind on the right, behind at the left, in front on the right and in front at the left. Thus, it is necessary to use the device of pumping of the brakes, available on sale in service department.

Brake liquid gets to a spare tank and is compressed thanks to preliminary pressure of the device of pumping of brakes via the main brake cylinder and via the hydrounit in the wheel brake cylinder. The carving stopper of removal of air of the corresponding pumped-over contour of a brake drive (in an example for in front on the right) opens. All other carving jams of removal of air are closed.

During pumping it is possible to press a pedal for maintenance of preliminary pressure and, therefore, for result improvement. The corresponding contours of a brake drive should be pumped over, does not come to light yet and brake liquid without bubbles and foam is not distinguished. Pumping logically should be repeated on other 3 wheels.

On the following hydraulic scheme of ABS 8.0 system the correct pumping on a forward left contour of a brake drive is shown on an example.