I assume you have these insturctions...
In the instructions you are instructed to connect everything, then turn on the transmitter and then the receiver (battery to the car).
The light should then show solid green.
Hold the trigger to apply as much brake as you would like when the failsafe engages then hold down the set button. Light goes orange...let up off the set button...light goes green. You should be set.
If all that doesn't work...try having the transmitter on and in the break position...hold the set button then turn on the battery to the car...see if it will set itself then.
By the way...there is nothing wrong with your car selection and traxxas makes very good products.