The invention relates to a system for arranging electronic control units (ECUs) in a chassis of a vehicle. The system comprises a set of ECUs arranged on corresponding circuit boards that are arranged in corresponding casing members. Each casing member comprises a frame structure extending circumferentially in a plane substantially parallel to its corresponding layer. Each circuit board extends in a plane substantially parallel to its corresponding layer and is arranged inside the frame structure of the corresponding casing member. First and second end plates are arranged at opposite end portions of the layered structure. The first end plate is adapted to be connected to the chassis of the vehicle, and at least one connection member extends along the layered structure between opposite end portions thereof. The at least one connection member is configured to be connected to the first and second end plates to hold the layered structure together.