EOL means "End Of Line", also known as the Proxy Alignment Procedure. EOL OK means the procedure has been carried out successfully.
At the end of the production line at the factory, the vehicle is connected to a computer which tells the Body Computer which electronic systems (known as NODES) are fitted to the individual vehicle. Once the BC has this information, it, and all the NODES can communicate with each other via the CAN (Control Area Network) connections.
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