dont get desperate.
first of all. all e36 have a trunk mounted amplifier for the speakers. the output from the radio goes to the trunk, to the amp, then to the speakers.
the amp is hidden underneat the trunk carpet on the drivers side, us spec.
the adpter you got is an universal bmw adaptor i've seen them i know what you mean.
go to the link below and follow the wire diagram.
The reason you got no speaker action, is because to turn the amp on the trunk on, there is a wire that send +12v to the amp, this un turn turns a relay on inside the amp and then the amp can work. this wire is called the remote wire. it sends power to the amp and the diversity antenna, which is on the rear widnshield, the radio antenna is integrated with the electrical defroster.
the link is for a 95 e36, but it should work, if needed, just google e36 radio diagrams.. http://www.unofficialbmw.com/e36/stereo/e3...reo_wiring.html
note, the link has the wiring diagrams for the radio and for the amp. if its only the radio plug diagram you need, this will work, but if you need the diagram for the amp too, then you have to look specifically for e36 made from 92 to 93, as in those 2 first years BMW offered a sound since that was replaced by the HK system of amp and speakers and so the wiring pins and plugs are different. But for the radio plug it should all be the same..
hope this helps.