I checked all connections, then sent my speedometer to a VDO authorized repair shop here in PA.
They called today, but I couldn't answer the call at that time. The voicemail informed me that what I sent them could not be repaired, but I could buy from them a reconditioned unit for $675, including shipping. I imagine they will ship my "irreparable" unit back.
I'll call them tomorrow to get more details. (core, condition, warranty, etc.)
Does this sound reasonable?
Thank you for your responses.