Volvo Electrical issues/ Abs Light

[Copper]

Thanks for the replies Windowratler and Snailexpress, so here's what I figured out so far. I reinstalled the old ec-60 ecm and that fixed the power supply code.

However now there is a new code "blink code 11-2". Which according to that ec-60 troubleshooting manual is a J1939 retarder Error. Does anyone know where this retarder is located? From what I understand reading that guide the problem actually lies in the j1939 data link. The brake ecu needs to talk with the engine ecu. Which this this faulty data link is preventing thus the abs light. Does that sound right to you guys or am I way off?