The E30 3 series was introduced at the end of 1982. It came available in 1983. It was available as 316, 318i, 320i and 323i. The E30 was sold from 1982 through 1991 in sedan form.
The following electrical troubleshooting manual and wiring diagram apply for the BMW E30 318i 1984 model year. This manual is intended to show electrical schematics in a manner that makes electrical troubleshooting and repairing activities easier. All the electrical parts and components which work together are shown together on one schematics/ circuit. At the top of the wiring diagram/electrical schematic, there is a fuse that power the circuit. The flow of current is shown through all wires, connectors, switches and motors to ground at the bottom of the page.
This manual is divided into following sections: Index, How to Use This Manual, Wiring Diagram Symbols, Wire Size Conversion Chart, Systematic Troubleshooting, Diagnostic Connector, Power Distribution Box, Fuse Data, Schematic Diagrams and Components Chart and Figure. The wiring diagram/electrical schematics shown in this manual covers power distribution circuit, fuel control, idle speed control, vacuum advance, charging system, wiper/washer, speedometer/indicators, service internal system, headlights, brake warning system, etc.
Find more information about BMW E30 318i Wiring Diagram and Electrical Troubleshooting Manual here. (source: armchair.mb.ca, wikipedia.com, bmwinfo.com).
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