BMW 3 series E46

Since 1998 of release

Repair and car operation

Brake system

Specifications

Separate characteristics are resulted also in the text of the Head and in case of compulsion of their performance are allocated by a bold type

The general parametres
Design	Disk brake mechanisms on forward and back wheels. Disks of forward brake mechanisms - ventilated. Disks of back brake mechanisms - ventilated except models 316i and 318i. Elektronno-hydraulic system of antiblocking of brakes ABS. The braking Monitoring system on turns CBC. Hydraulic system - two-planimetric, diagonal. Drum-type mechanisms of a lay brake on the back wheels, equipped тросовым a drive
System of antiblocking of brakes ABS	Dynamic system of stabilisation of stability built in in ABS DSC3 on early models Е46 anti-slip system (Teves ABS/ASC Mark20ET)
Thickness of overlays brake колодок disk brake mechanisms
Deterioration limit (without a back plate)	3 mm
Thickness of overlays brake колодок drum-type brake mechanisms
Deterioration limit	1.5 mm
Brake mechanisms of forward wheels
The minimum admissible thickness of a brake disk	20.4 mm
Diameter of a brake disk
316i, 318i, 320d, 320i, 323i	286 mm
328i, 330d	300 mm
Brake mechanisms of back wheels
The minimum admissible thickness of a brake disk
316i, 318i,	8.4 mm
320d, 320i, 323i, 328i, 330d	17.4 mm
Diameter of a brake disk
316i, 318i	280 mm
320d, 320i, 323i	276 mm
328i, 330d	294 mm
Admissions of the sizes and palpation of brake disks:
The maximum size of processing on the party	0.8 mm
The admission of a thickness of a brake disk	0.01 mm
The maximum lateral palpation
It is established	0.2 mm
It is removed	0.04 mm
Lay brake:
Diameter of a brake drum	160.0 mm
The maximum radial palpation of a brake surface	0.1 mm
Brake liquid	1.5 l DOT of 4 specifications FMVSS 116
Efforts of a tightening of carving connections
The moments of an inhaling of fixture are resulted also in the text of the Head and on some иллюстрациях*. *Выделенные in the text a bold type the inhaling moments are subject to exact observance; the efforts not allocated with a bold type are resulted only roughly
Directing bolts of a brake support of forward wheels	28 Н•м
Mudguard, ahead	10 Н•м
The lever of a lay brake on a body floor	25 Н•м
Brake hose on a support	235 Н•м
Bolts of wheels	120 Н•м

The brake system consists of the main brake cylinder, the amplifier of a brake and disk brakes of forward and back wheels. The brake hydrosystem has two contours: one contour influences forward wheels, another on the back. Thanks to it at refusal of one of contours car braking is carried out by other contour. Pressure of a liquid in brake system is created in the dual main brake cylinder by pressing a brake pedal.

The tank with a brake liquid is located in an impellent compartment on the left side over the main brake cylinder. It provides with a liquid all brake system. The amplifier of a brake at the block of cylinders accumulates a part of the vacuum created by the engine at всасывании. Through the valve the effort of a pedal of a brake if necessary amplifies vacuum. As the diesel engine has not enough the vacuum created at всасывании, the vacuum is created by the special vacuum pump located on a head of cylinders.

Disk brakes are equipped by supports with one cylinder.

The lay brake is set in motion through тросовые draughts and influences back wheels. As the disk brake is inefficient as lay, on back wheels there are in addition two drum-type brakes which have been built in brake disks. Drum-type brakes are put in action exclusively through the lever of a lay brake.

Work with brake system demands special cleanliness and an order. If necessary experience of such work is absent, she should be spent on HUNDRED. It is recommended to apply brake Pads, resolved by the manufacturer of the car. At movement on wet roads it is necessary to press periodically brakes to dump from brake disks deposits. At the expense of the centrifugal force arising at rotation of wheels, water leaves from brake disks. However on disks there is a thin film of silicone, greasing and pollution which reduce efficiency of action of brakes. Dirt on brake колодках and rain flutes lead to formation задиров on a surface of brake disks. All it promotes decrease in efficiency of braking. At clearing of brake system the brake dust is formed. This dust is unhealthy. Therefore at clearing of brake system, watch to inhaling a brake dust.

Systems of stabilisation of stability of the car on road ABS/CBC/ASC + T/MSR/DSC

ABS: the Antiblocking system interferes with blocking of wheels at sharp braking of the car. Thanks to it even during braking the car remains operated.

Continuation ABS is the braking monitoring system on turns СВС (Cornering Brake Control). СВС on signals of four gauges ABS learns that the car moves on turn. If braking occurs on turn, it usually leads to that the car tries, as though to be screwed in turn. This effect is a consequence of increasing loading on a forward axis. The braking monitoring system on turns СВС regulates increase of brake effort in such a manner that it accrues faster on external in relation to turn a forward wheel, than on other wheels. Thus, action, the return to the effect specified above is created. СВС on turns works practically as system of electronic distribution of effort. Thanks to it there is possible an influence on back wheels with the big brake effort.

АSС (the system of automatic stabilisation) reduces a twisting moment both drivers wheels by reduction of capacity of the engine when wheels at car dispersal start to be turned.

In the presence of the monitoring system of effort coupling (+Т) at трогании the car from a place turned wheels are braked. As a result of it the twisting moment is switched to "linked" wheels. The considered system practically operates as electronic blocked differential which is disconnected at speed over 40 km/hour. System ASC use + Т is displayed to the driver by fire of a control lamp.
The system of regulation of traction moment MSR is integrated into system ASC + Т. This system interferes with blocking drivers wheels on equal road at the expense of brake action of the engine at switching on lower transfer or at gas reduction.

At movement of the car with snow chains in deep snow or at трогании from a place from a deep dirt it is expedient to disconnect system ASC + Т by means of the switch on the central console. At repeated inclusion of the specified switch or at following start of the engine system ASC + Т again automatically joins.

The system of the dynamic control of stabilisation DSC is established as the additional equipment on model 328 i. System DSC Monitor constantly spends comparison of current parametres of movement with the parametres of an ideal condition received by a settlement way. If, for example, the car at movement on turn too strongly недоуправляется, capacity of the car and, hence, speed of movement decrease, simultaneously the system brakes a back wheel, internal in relation to turn. Thanks to it the turned forward wheels create more than a lateral direction and the car does not leave turn.

Instructions on systems ABS/CBC/ASC + T/MSR/DSC

The safety scheme in the electronic block of management watches that in the presence of defect, for example, cable breakage, or at too low voltage of the storage battery (more low 10) the system was disconnected. At normal work after ignition inclusion the control lamp lights up for short time and then dies away. If the lamp does not die away and in the course of movement continuously lights up, it specifies in malfunction presence. The car can be maintained further, but the system of electronic regulation is disconnected.

If in the course of movement one or several control lamps on a control panel light up, pay attention to the following:

1 Stop the car for short time, switch off the engine and again start it.
2 Check up pressure of the storage battery. If it less than 10.5 In, charge the battery.

If in a start of motion control lamps light up, and then through short time die away, it specifies that in a start of motion pressure of the storage battery was low, then during movement the battery was charged from the generator.

3 Check up, whether plugs of the storage battery are tightened and whether there is a reliable contact.
4 Lift and establish the car on supports. Remove wheels, check up external survey presence of damages of wires of gauges of number of turns of wheels (presence of retyrannies). More careful check of system ABS/CBC/ASC + T/MSR/DSC should be spent by means of special devices. Address to Section Diagnostics of malfunctions. Work it is desirable to spend HUNDRED in conditions.

Before carrying out of electrowelding works it is necessary расстыковать a socket of an electronic monitor. Undocking should be made only at the switched off ignition. At carrying out of painting works it is authorised to subject a monitor to short-term influence of temperature to +95С, and долговременно (no more than 2 hour) – to temperature +85С.