Accessory Wire
 

Finishing up the radio installation from months ago, and can't remember where the radio wire labeled accessory goes. The stock wiring in the W123 was butchered, so have to hardwire. :( So, there is black, red, brown, and grey in what had a four pin connector, then a separate black wire. I am thinking it was doubled up with one of them. Does anyone know?

Thank y'all in advance! :D