So I am trying to restore my 1991 vr4. It didn’t come with a radio. Where the radio goes there are 5 plugs. I know two go to the radio, but I’m not sure what the other white plug, the black plug and the blue plug are for. I will attach some pictures for reference.
Black plug with yellow wire is steering wheel controls
The blue plug connects to the other blue plug hanging just above that. It’s the annoying beep when the door is open
The 3 white are radio plugs. The one in your hand comes from the silver box in the blue plug picture. That is actually a factory amp. There should be a 6 pin din cable in there somewhere. That also plugs into the factory radio and comes from the amp. It loops itself. Let me know if you have any other question