Automotive Wiring Diagrams

diagram for automotive relay

Watch the Diy automotive wiring diagrams video at the bottom of the page to find out how to pinpoint electrical problems like a pro. Read your way down to gain additional knowledge on the subject. My Name is Mark and I am a Certified Master Technician.

Wiring diagrams are drawings of electronic systems. This repair diagram is the quickest way to auto repair success when dealing with complex electrical problems on any vehicle. On this page you will find some solid information required to understand, diagnose and repair difficult car electrical problems.

In the drawings below are some of the most common electrical symbols you will find in automotive wiring diagrams. Memorizing what these symbols stand for can speed up your understanding of the given circuit which intern leads to faster detection of system malfunctions.

In the electrical schematics to follow you will see symbols are arranged in a circuit to reflect the function, power state, and relative location of various components.

An electrical symbol may have a slight resemblance to the actual component or its main function. Be aware solid and dotted lines represent energy that flows in and out of component connection points.

Abbreviated text labels or codes placed next to the symbols and lines aid in providing descriptions. Both All-Data and Mitchel 1 provide a depository of electronic auto repair schematics related to specific model electrical repair. Each section has links to the DIY automotive wiring diagram to help decipher the controls of that system.

Automotive Wiring Basic Symbols

electrical symbols defined

Automotive electrical diagrams provide symbols that represent circuit component functions. For example, a few basic symbols common to electrical schematics are shown as: (1) Switch, (2) Battery, (3) Resistor and (4) Ground.

Note the switch symbol displays an open or closed circuit path, which is what an actual switch performs. The battery symbol appears to be made of layers or plates, common to internal battery construction. The resistor symbol appears to impede energy flow, which is a resistor function.

The G100 ground symbol indicates a connection pointing downward (ground) that dissipates energy. The G100 designation is to help you find this location on the automobile. Factory service manuals provide component location diagrams including important ground locations.

Variations of symbols will exist depending on function or other characteristics. Examples are: Variable Battery symbol (5) and the Case Ground symbol (6). Electrical repair diagrams are mostly standardized for the above symbols.

Auto Wire Diagram Advanced Symbols

electronic symbols

Abbreviated codes on the diagrams provide circuit path and part or component information. The codes or labels may be used to show circuit connector pin numbers, circuit values or component polarities will add clarity to the diagnostic drawing.

These sets of label examples are: (1)A for Amperage or Amps. (2) ORN for wire diameter and color (3)1340 for Circuit Path ID (4)P for pass through grommet (5)A for Pin ID & Location (6)C1 for Terminal Connector ID (7)B+ for battery positive.

Automotive Wiring Electrical Symbol

electrical wiring symbols

At first glance the repair diagram may not convey how wires are of many colors and diameters. The diameter of each wire symbolized is indicated by a label placed at some point along side its drawn line (1)(0.8).

Being aware of the color of a wire is important.(2) Wire color information is provided as a color code label in this case black/white. (3)Also shown are common schematic illustrations of wires, (4)wires connected and (5) wires crossed but not connected.

For consistency most electrical schematics have signal or energy flow from top to bottom. Component inputs on the left and outputs on the right. Providing an understanding of how a system would function makes the wiring repair diagram one of the most valuable resources a technician can use in repairing a vehicle.

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I wanted to let you know a little more about the way to get the exact Do it yourself wiring diagrams for you're specific vehicle on the cheap. People ask which one is better a one month or 1 year subscription. Or what company is better Mitchell or All Data? It's like Ford and Chevy Pick up trucks! Both have loyal fans.

Alldata-diy repair manuals offers a 1 year subscription for around 27 bucks at the time of this writing. No coupon code to enter at checkout because it's the regular price at this time. Now there is no excuse not to access the automobile wiring diagrams that professional shops would have.

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These are about the same schematics in dealership manuals because they pull data from factory publications. You can print out what you need and take them right to the vehicle! So in short (electrical pun intended) you can subscribe to this for a month and find and print all the wiring diagrams for your specific vehicle for around 27 bucks and have them for life.

Another update: I have purchased a subscription to E auto repair for my own vehicle so I could make a video demonstration of what that looks like. View the demo video for this program that puts auto repair online.

A wide variety of do it yourself automotive information can be found on the page I built dedicated to DIY auto repair tips.

More information on the use of automotive wiring diagrams. Take a look at 2 golden rules for using electrical troubleshooting manuals.

My latest video on my website has some advanced tips for using electrical diagrams to solve car problems. This is the method I use every time I break out a wiring diagram.

Find out more about me and this website. Also discover what gives me the right to talk about automotive wiring diagrams. This next link takes you to the homepage from this article about car wiring diagrams.

Specific answers to car electrical problems!