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 versions of engines is applied.

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

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

It is possible to determine by measurement of temperature in the hydrounit by the characteristic whether there is a danger of an overheat of the brake system at the 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 by 25% thanks to modern microprocessor technology. At the same time the external sizes changed and, therefore, knot volume decreased by 30% in comparison with the ABS 5.3 system.

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

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

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

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

Depending on option of the ABS 8.0 system weight also differs.

The assembly provision of knot of the control unit of ABS/gidroagregat in the Corsa-C model horizontal. The hydrounit engine with its axis is mounted in horizontal position, and connections of separate contours of the 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 the 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.

The control of the pump electric motor in the hydrounit of the ABS 8.0 system is made through a pump housing. Electromagnetic valves of the hydrounit are put in action via electromagnet coils. These coils are directly connected to the semiconductor relay in the ABS control unit and, thereby, are 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. Consolidation of the ABS control unit separately is not on sale. At 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.

This block should be replaced 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 state, 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 cover of the ABS control unit cannot be pressed at all. It results in defects invisible externally in the control unit (ASG). At installation it is necessary to take the ABS control unit only by the outer edge of the case and to pay attention to installation without efforts.

The ABS control unit cannot be attached to the hydrounit by means of fixing screws at all. It leads to damage of the ABS control unit and/or hydrounit.

Replacement of components of the ABS 8.0 system, especially in the field of control unit knot 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 state is connected to the ABS control unit. At execution with the ESP system the sensor of pressure is not installed outside on the hydrounit any more as at the ABS 5.3 TC/ESP system, and it is 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 the ABS 8.0 and ABS 8.0 E systems. Diameter of hydraulic connections also differs between execution of ABS 8.0 and ABS 8.0 ESP so installation of wrong version of the hydrounit is not possible.

The spring contact pins established on the face surface of the ABS control unit should not concern because of the possible electrostatic category, and it is not necessary to take any measurements. Spring contact pins separately are not replaced. In order to avoid damages, the gilded surface of contact pins cannot also be processed or subjected mechanically to processing by liquids, such, such as liquid for processing of electric contact connections at all.

Also it is impossible to take 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 valvate block to the ABS control unit.

In the ABS 8.0 ESP system the sensor of pressure is not installed outside on the hydrounit any more as at the ABS 5.3 TC/ESP system, and it is 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.

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 the brake system. Thus, for example, is defined whether there is a danger of an overheat of the brake system at the movement under a bias. Thanks to process of braking at the movement under a bias disks of the brake mechanism heat up so strongly that the formed warmth is transmitted by brake disks through a bracket of the disk wheel brake mechanism on brake fluid. Thus, temperature in the hydrounit also increases.

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

self-diagnostics function;

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

2 analog outputs 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 B post. Current.

Pressure sensor separately is not replaced. The contact plate for pressure sensor in the ABS block, also as spring contacts 1, has a gilded surface. It does not need to be subjected to machining.

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

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

Shtekerny connection on the ABS control unit is executed 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 with one sealing laying on the socket of a plait of wires are provided. Amount of power contacts (2,8 x 0,8) mm.

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

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

Watch the drawing with the flowchart of a hydraulic actuator – ABS 8.0.

Removal of air comes from a hydraulic actuator of the ABS 8.0 system in the sequence behind on the right, behind at the left, in front on the right and in front at the left. At the same time, it is necessary to use the device of pumping of brakes which is available on sale in service department.

Brake fluid gets to a spare tank and compresses thanks to the 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 the brake drive opens (in an example for in front on the right). All other carving traffic jams of removal of air are closed.

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

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