BMW 3 of the E46 series

since 1998 release

Repair and operation of the car

Explanatory remarks to schemes of electric connections

The schemes of electric connections provided further are made by the schematic principle when components of each contour communicate among themselves on the shortest way without a form of laying of an electrical wiring round the components and plaits located on the way of its following.

On BMW cars the single-wire scheme of turning on of devices of electric equipment is applied. To plus of power supplies consumers unite a wire, and to minus – through a body of the car or on weight. Such method allows to reduce number of wires and to simplify their installation. Connection with the mass of minus of power supplies reduces electrochemical corrosion of metal details of a body. In certain cases it is not enough direct connection of the electric consumer with weight, and the consumer unites to weight an additional wire of usually brown color.

The supply voltage is brought to most of consumers via the ignition switch. Power-supply circuits of those knots of electric equipment which work can be demanded in any circumstances, are always connected to the battery, irrespective of the provision of a key in the ignition lock.
For connection of wires electric sockets with flat contacts are used.

For normal food of consumers the electric chain has to be closed, otherwise at it there will be an electric current, for example, if to the electric motor of a screen wiper positive tension moves, it will not work until its electric chain is not connected to weight. In an electric chain switches, the relay, safety locks, measuring devices, electric motors and other consumers of the electric power can be connected. For the correct connection of consumers of the electric power contacts of electric sockets have the corresponding markings. Connection with the mass of the car is carried out or directly via the case of the consumer of the electric power or an additional wire.

Contact 30

On this contact always there is positive tension of the accumulator. The wires connected to this contact have color, red or red with a strip.

Contact 31

Contact connects to the mass of the car a wire of brown color.

Contact 15

On this contact positive tension after ignition inclusion moves. The wires connected to this contact have color, green or green with a strip.

Contact of X

On contact tension after ignition inclusion moves, however at inclusion of a starter tension is disconnected. It gives the chance at start of the engine to disconnect consumers of the electric power, unnecessary at this moment. Headlights of a driving beam receive food also from this contact therefore at the turned-on driving beam and switching off of ignition there is an automatic switching on marker lights.

Colors of wires are designated by Latin letters.

If in designation of color it provodaimetsya some letters divided by a sign/, the left group of letters indicates primary color of a wire, and right – for color of a strip.

On the scheme all consumers of current and switches are represented in neutral situation.

Designations of flowers of isolation of an electrical wiring *

BLK	The black
BLU	The blue
BRN	The brown
GRY	The gray
GRN	The green
LT	Light (shade)
NCA	It is not defined
ORG	The orange
PNK	The pink
PPL	The purple
RED	The red
TAN	The golden
VIO	The violet
WHT	The white
YEL	The yellow
* OR	OR
For example: BRN/VIO OR GRY/BRN — Brown with the Violet strip or Grey with the Brown strip