I have a 2003 Honda Accord lx v6 high mileage ... problem started yesterday, while I drive the car turns on and off. Today it turned off completely and I had to take out the key and turn it on again. The TCS and the ABS lights flashed on ...

 

Not a whole lot to go on here.....I'd inspect the battery cables (both ends of both cables) to be sure they are clean and tight.

Next I would have the battery tested - when you remove the cables a nice time to take the battery for testing.