E01 and E02 apparently connected to Ground Point B.
http://www.cygnusx1.net/Supra/Librar...=Main&Page=148
http://www.cygnusx1.net/Supra/Librar...n=Main&Page=26
This is the Pinout for the '89 N/A There are a couple additional connections that aren't present or used on the pre89 models. The pinout for power and ground point is accurate though.
http://www.cygnusx1.net/Supra/Librar...ion=FI&Page=31