On Wed, 16 Mar 2016 22:50:06 -0500, legg wrote:

Looked to me more like dye concentrating as the curing epoxy puckered.

So not likely to cause a fault then?

Did you ever reset this thing, while it was still in the vehicle?

No. I think if the fix were that simple the service specialists who
swapped the unit over wouldn't have gone to the trouble of sourcing a
replacement. They charged me next to nothing for the job so I trust them.