The E24 was a replacement for the CS and CSL coupes, production started in March 1976 with two models: the 630CS and 633CSi.
The following electrical troubleshooting manual provides detail information about the entire electrical system, components descriptions and electrical testing and troubleshooting for BMW E24 633CSi 1983 model year. This manual is divided into following sections: Index, How to Use This Manual, Electrical Circuit Symbols, Wire Size Convertion Chart, Systematic Troubleshooting, Diagnostic Connector, Power Distribution Box, Fuse Data, Schematic Diagram, Component Charts and Figures. All wiring between components is shown exactly as it exists in the vehicle; However, the wiring is not drawn to scale. To aid in understanding electrical operation, wiring inside complicated components has been simplified.
Find more information about BMW E24 633CSi Electrical Troubleshooting Manual, Wiring Diagram, Electrical Circuit, Connectors, Fuse and Relays here. (source: armchair.mb.ca)