Model of power cables with ropes/lianas hanging from them (Land_vn_misc_cable_ep1) has collision on both the cables and the lianas. As such, depending on how low they hang, vehicles driving under them will hit them. However, unlike the poles they're attached to, the cables/lianas are indestructible.

This will naturally lead to a big confusion on the part of driver (who'd expect his vehicle to break the cables), damage to the car, and (in worst case scenario) having vehicle stuck between cables and groud, with any action taken to move the vehicle (by script or Zeus) resulting in it's rapid unplanned disassembly.

It seems that removing collision from the cables (or at least the ropes/lianas) would be the best course of action - the other option would be to make them destructible like poles, but the resulting animation may not look particularly nice.