What causes warning message 725 (e.g., “While traveling on lane 1 on link (2, 3), vehicle 4 no longer has a candidate lane on which to travel.”)?
Various downstream geometric objects, such as off-ramps, lane drops and incidents, force vehicles to avoid certain lanes. When warning signs for those objects are not located correctly, the result can be that there are no lanes that should not be avoided by some, or all, vehicles. A vehicle is in that situation will ignore the warning signs and stay in its current lane, which can cause vehicles to get stuck at lane drops or incidents, or take the wrong exit. Vehicles begin to react to the geometric objects where the warning sign is located, so the combined effect of the warning signs must allow at least one lane that can be used by the vehicles that have crossed the warning sign.
