There is actually a timer motor, that is hooked to the dial switch on the back side of it. Sounds like the timer motor is bad. Which most of the time there too slow or never move at all.

Turn breaker off to washer, and remove screws to inner plastic molding around door, then you will see the timer. You will notice a small motor mounted on, or near the dial switch. This is the timer motor and will have (2) small black wires coming out of it. Take it off and get a new one. Not very expensive.

Last but not least, the timer itself(dial switch you see from outside) could be bad. But try the timer motor itself first. Let us know.