What model timer do you have? What model pump do you have?
Is your pump 120V or 240V?
Do you have a multimeter? Check there is voltage on the LINE wires into the timer. If you have voltage there turn the pump on the timer and check if you have voltage on the LOAD terminals of the timer.
Show us pics of the timer, the inside wiring of the timer, and your pump wiring and data plate.
Something had to cause the circuit breaker to pop.. I doubt it was the breaker itself..
As Allen points out, you need to test the voltage at the input and output of the timer.. If you have voltage at the input to the timer and no voltage at the output of the timer, then the problem is the timer.. If you have voltage at the output of the timer, then you need to test the voltage at the input to the pump. If you have voltage at the pump, and it is not running, then your pump is the problem.
Keep in mind that if your system runs off of 240 volts, you must test between the two input pins to see 240.. Testing each input pin to ground will not give you a valid reading..
Thanks for the info.... weird thing about this timer and pump they are on a shared on the same breaker.. not sure what else is on this breaker. The house is my mother in laws and shes the second owner. When testing what do you set the multimeter too. I am a fixer/repairer dont mess with electricity too much. Pump on off switch is tied Into the timer so only way to manually turn it on is there... timer was ticking.. so not sure if..something iswrong internally.. I'll post some pics.. in a min.. away from the house