Servo rotates uncontrollably when powered on

A few weeks ago, the XRP was working well. I was able to program auto movement including servo movement. Today, when I took it out of the box again and powered it on, the servo started rapidly moving back and forth across its full range of motion. I re-imaged the XRP and also tested the servo in the servo 2 port. Neither one had any effect.
I’m hoping the servo’s not dead. This XRP has been nothing but fragile since I started working with it.

The servo has 3 connections. 2 are for power and ground, the third is a PWM control signal. The PWM signal will be an approx. 50Hz signal with a positive pulse width between 1000-2000 micro seconds.
Can you verify what the PWM signal is doing when the servo is moving erratically?

Thanks, how do I check the PWM signal? Also, I checked it again today and instead of the erratic movement, it went immediately to the down position and stayed there.

Just as an FYI, when you turn the XRP on it will run the last program that was run with XRPCode. That may be why you are seeing the servo move.