Top right by the orange mark is the pressure sensor. They fail at a high rate. When they fail the weep hole leads directly into the compartment shown. It does not leak to atmosphere. There is no weep hole in this compartment. You can see the traces of DEF everywhere. Now look at the bottom left. Thats where the plug is. So the compartment starts filling with DEF and its only outlet is the wiring harness. Its literally pressurizing the DEF into the harness.
But wait, theres more.
After the DEF enters the harness what is going to stop it? So now the DEF harness - or whatever it is called - is ruined but the DEF keeps going to the main harness contaminating and destroying it as well. At this point a simple sensor failure has caused $10,000 in damage!
But wait, theres more.
It didnt happen in this case but the DEF can even make its way into the ACM. My guess is if that happened it would be an additional $5,000.
Someone needs to redesign and recall this system. It has a cascade of engineering flaws that lead to cascading failures.