To cope with the rising complexity of automotive electric/electronic architectures (EEA), model-based development at system level is well-established and typically realized in architecture description languages (ADLs) and high-level tools. In this paper, we extend a previously developed approach for automated cross-domain simulation synthesis of model-based EEA descriptions enabling system-level evaluation by a behavioral specification layer. The key contributions of this work are modeling extensions applied to a state-of-the-art EEA ADL to refine specified behavior during synthesis with electric circuits including wiring harness details modeled at the hardware layer. Preliminary experiments show that the novel combination of quantization- and SPICE-based synthesized circuit simulation, conducted in a discrete-event manner and applied to a buck converter, a typical device in an automotive EEA, increases simulation efficiency up to a factor of 2.0 compared to other state-of-the-art tools while preserving accuracy. Finally, another example EEA hardware network, modeling the dynamic current consumption of an Electric Power Steering actuator, applied to a realistic vehicle topology model demonstrates the impact of wiring harness refinements.