355 F1 Transmission Problem

My 1999 355 F1 has recently begun to flash the transmission light (far left). This does not happen all the time and there is not a clear pattern (although it happened 3 times yesterday). It seems to occur after transitioning from highway driving to non-highway stop and go driving. AC has been on with this occurs. Perhaps heat? When the light flashes and I am stopped at a traffic signal, the transmission shifts to Neutral and I must shut down the engine and restart in order to drive. It has occassionaly flashed when I have been driving non-highway and I have not been able to shift out of gear (once 1st and once in 4th). It has not occurred on a highway yet. Ideas?

Just last week I had a F1 fault come on a few times as I drove home from work. In my case the car is a 2001 360 spider. In hunting down possible reasons yesterday I found that the F1 fluid was very low; well below the minimum mark. Refilled with Mobil 1 ATF (Dexron III compliant) but haven't taken it for a long ride yet.

Thanks for the response. My fluid level is not low, so still searching.

Sounds like you need a Dealer to plug in the Fault Reader Equipment...and let them pull out the error codes. I would do this sooner, rather than later because there is always a chance you can catch something simple and take care of it before it because bigger and more expensive.