Hey Bruce, just came across your msg today.
You have probably resolved your issue by now.
I had to replace the multi-function switch located on side of transmission.
Part No. 986 325 612 01 Expensive though.
All good thus far.

Hey Sammie. I have a 986. Just had local independent shop do a transmission fluid service on my car including adjusting gear selector cable. Was getting flashing R indication. While driving did have current gear indicators light. Now after service flashing D and no gear indicator indication. Did you get your flashing D resolved. Irritates me that I pay for repair an issue remains or new issue once repair is made. I’m a mechanical engineer and design automated assembly machines. I can’t get away with this at work, expect the same of others. Wish I had a larger garage so I could work on my own car.

Hey Sammie. I have a 986. Just had local independent shop do a transmission fluid service on my car including adjusting gear selector cable. Was getting flashing R indication. While driving did have current gear indicators light. Now after service flashing D and no gear indicator indication. Did you get your flashing D resolved. Irritates me that I pay for repair an issue remains or new issue once repair is made. I’m a mechanical engineer and design automated assembly machines. I can’t get away with this at work, expect the same of others. Wish I had a larger garage so I could work on my own car.