Understanding European DIN Wiring

1 Understanding European DIN Wiring BY KARL SEYFERT. European Wiring diagrams may look strange and incomprehensible. But they're not so tough to understand when the underlying standards are explained. O. ver the years, I've ignore the differences of language and heard many explana- culture, isn't it still a difficult problem tions for why some for a European manufacturer to build technicians choose not vehicles in a different country like the to work on European To oversimplify the challenges vehicles. For some, it's involved, how do you get an American based on their desire to work only on assembly line to crank out parts for a vehicles built within our borders. For European car? The answer is stan- others, the choice may be based on the dards.

2 Standards have been an integral belief that European cars are just too part of the automotive world since the foreign and their systems too unusual earliest days of the automotive assem- or exotic to easily understand. bly line. Standardization of parts al- In today's automotive economy, it has lowed automakers to transform their Fig. 1. become increasingly difficult to hold businesses from a one-at-a-time propo- onto these attitudes. Many cars sold in sition to a many-at-a-time operation. world, as long as it conforms to the this country by European (and Asian) In this country, the Society of Auto- same set of standards. manufacturers are actually assembled motive Engineers (SAE) is responsible In Europe, the most widely recog- right here in the This blurs the for maintaining order by establishing nized organization responsible for es- conventional definition of an imported many of the standards that apply to au- tablishing and publishing automotive vehicle.

3 At the same time, many Amer- tomobile manufacturing. When you standards is called Deutsches Institut ican cars are actually assembled out- pick a bolt for a domestic vehicle out of f r Normung Standards estab- side our borders, further confusing the the bolt bin, chances are the standards lished by this organization are often re- accepted definition of a domestic car. and specifications concerning its ferred to as DIN standards. Auto manufacturing is truly a global thread pitch and hardness were origi- DIN standards have been estab- enterprise, with all of the major manu- nally defined by SAE. Thanks to stan- lished for a multitude of things, includ- facturers conducting business in sever- dardization, that bolt should thread in- ing many outside the automotive al countries simultaneously.

4 Even if we to any nut made anywhere in the world, but we'll limit the focus of this 38 April 2003. Fig. 2 Fig. 3. article to the DIN standards for auto- always represents a direct connection to motive Wiring . Why Wiring ? Because WIRE COLORS the battery positive terminal. And ter- that's the one thing I've heard the most English DIN (German) minal 50 is always battery positive with techs complain about when it comes to Black ..Sw the key ON or in the CRANK position. Blue ..Bl working on European vehicles. For Brown ..Br some, it's the layout of the electrical Green ..Gn Wire Color Codes components throughout the vehicle. Gray ..Gr Before we get into some actual DIN. For others, it's Understanding the Orange.

5 Or Wiring diagrams, a word about wire Pink ..Rs Wiring diagrams that map out the posi- Purple ..Vi color codes. Most Wiring diagrams tion and operation of all those systems Red ..Rt you're likely to come across will have and components. The diagrams may Turquoise ..Tk already been translated into English. look strange and incomprehensible. White ..Ws Wire colors in those diagrams should Yellow ..Ge But when you understand the underly- be labeled with abbreviations you'll be ing system and standards that were able to understand. But just in case used to design the vehicles and the dia- many of the common terminal desig- you run across a diagram with the orig- grams, it's not as tough as it first seems.

6 Nations described under DIN 72 552. inal Wiring color codes, use the Wire Some of the more obscure numbers, Colors key at left to sort things out. By Terminal Designations which refer to components on trailers, the way, color codes for electrical DIN standard 72 552 establishes the heavy-duty trucks and such, have been Wiring are defined in DIN 47 002. terminal numbering system that's used intentionally omitted. for any Wiring diagram or vehicle When you've worked with DIN Circuit, Block &. Wiring that conforms to DIN specifica- Wiring for a while, you'll begin to recog- Schematic Diagrams tions. The terminal codes are not wire nize certain numbers that come into Description of an electrical system or designations, as devices with differing play more often than others.

7 For exam- circuit may begin with a circuit dia- terminal codes can be connected to ple, a terminal 31 designation always gram. This is an idealized representa- the opposite ends of a single wire. The refers to a direct connection to vehicle tion, rendered in the form of symbols chart on pages 42 and 43 outlines ground and a terminal 30 designation to provide a quick overview of circuit April 2003 39. Understanding European DIN Wiring and device functions. The circuit dia- to see how the current flows through gram illustrates the functional interre- the various sections of the circuit. lationships and physical links that con- The diagram also includes informa- nect various devices. These diagrams tion on terminal numbers, wire sizes may also include illustrations and sim- and colors, connector sizes and a basic plified design drawings, as needed.

8 Representation of the internal working A block diagram is another simpli- of the gauges and sensors. The symbols fied representation of a circuit, showing used to define the components also only the most significant elements. It's conform to DIN specifications. A key Photos: Karl Seyfert designed to furnish a broad overview of explaining these symbols will often be the function, structure, layout and op- included with the schematic diagram. eration of an electrical system. This for- Even if you're fairly familiar with a mat also serves as the initial reference circuit on a given car, a schematic dia- for Understanding more detailed gram will help you find the correct lo- schematic diagrams. Squares, rectan- cation of a ground terminal, or help Most DIN relays include a miniature gles, circles and symbols illustrate the schematic diagram, right on the relay you identify a specific pin number in a components.

9 Information about wire housing. Flip the relay over and you'll connector. colors, terminal numbers, connectors, f ind the relay terminals are also Another example of a current flow etc., are omitted to keep the diagram as numbered. The numbers correspond schematic diagram is shown in Fig. 2. simple as possible. to the DIN terminal designations. (page 39). This diagram also explains The schematic diagram shows a cir- the meanings of some of the letters and cuit and its elements in detail. By pleting the circuit to the battery. numbers in the diagram. The way the clearly depicting individual current Occasionally, a wire in a circuit will components and wires are situated in paths, it also indicates how the electri- be continued in another current track.

10 Relation to one another in the diagram cal circuit operates. Most DIN When this happens, a small box with a usually bears no resemblance to how schematic diagrams are current flow number inside will send you to the cur- they're actually arranged on the vehicle. diagrams. They're arranged from top rent track where the wire is continued. Break this diagram down and you to bottom, so we can clearly see how Fig. 1 on page 38 is a schematic dia- can see how it can work for you. Four the current flows through the circuit. gram of the gauge circuits on a Volkswa- things are needed to have a complete In a current flow diagram, a large gen. The lines across the top represent circuit: a source of power, wires or con- block or several lines running across the positive feeds to the circuit.