My wife's car started doing this recently, 2 days ago.
Seems to only do it when the car has been sitting several hours and is cold.
HOld lamp flashes when key turned to RUN without starting engine.
Cycling the key between OFF and RUN does not make lamp stop flashing.
On first start of engine, lamp continues to flash.
Turning engine off and then re-starting stops the flashing. Car drives and shifts normally, fluid level is correct, fluid colour and odour are OK.
Seems to me like a sensor, rather than the tranny.
Anyone have any info that could help?
My Haynes manual is really skimpy on the transmission sensors and circuits.
Thanks in advance
Emil