A friends 02 Fatboy started flashing the 4 ways 3-5 times a few seconds after the key is turned on.
I found in the manual how to check this with the turn signal buttons.
It showed a code 31 alarm output low. This bike doesn't have security installed on it. I followed the manual stating the lt/grn-brn wire should either be open or grounded, I checked this wire and it is neither open or grounded.
I read where a couple of people pulled the connectors and cleaned them and the problem went away. These are sealed connectors and found no problems with them, others with this problem, never came back online to report how they fixed it.
Any thoughts as how to solve this problem? I'd hate to spend the money for a new TSM module and not have it fix the problem.
I've tried clearing the code with the turn signal buttons, but it comes right back.

Note: The only mod on this bike is the H-D run/turn/brake aux module, I have unhooked that and no change.

 

I have the same problem - throwing code 31, '02 FLH, no security, cant figure it out. Dealer mechanic friend offered no advice other than, "run it til it dies." Not good if on a trip. Intermittently, the code seems to clear itself, but then eventually returns. Any other thoughts? Did you end up replacing the module? My '02 has p/n 68920-01a, but dealer said superceded by 68920-01d.

 

Open/ground or power/ground? How did you test for open? The voltage on a line connected to nothing is arbitrary. It's like saying you're 12' above. Above what?