Damaged network wiring

Physical damage to the vehicle's communication bus wiring, which is worth naming separately from a module fault because the codes it produces name modules — plural — that are all in perfect health.

A bus is a shared pair of wires, so damage is not local in its effects. One chafed conductor, one crushed section behind a trim panel, one corroded splice, and every module that talks across that point reports lost communication with every module on the far side. Several lost-communication codes naming unrelated modules is the signature of the network, not of the modules — and it is the single most useful inference in this area.

The bus is also deliberately fault-tolerant, which hides the damage. One broken conductor of a twisted pair often lets communication continue in a degraded single-wire mode, so the vehicle works while errors accumulate. Measure resistance across the pair with the ignition off — around sixty ohms for a terminated bus, and a reading of roughly one-twenty means a termination or a section is missing. Look where the loom moves or passes a body seam: doors, tailgates and the joint between engine bay and cabin account for most of it.