Sometimes you’ll hear a loud crack or notice your springs are in two separate pieces. Another sign is that your door will start to open but then quickly go back down or only finish opening with help from you gently pushing on it
The opener light just blinks when you try to operate it. If it’s not responsive make sure it’s still plugged in. Also, make sure there’s nothing in the path of the sensors.
Your door will operate normally until it gets to the damaged piece and either stops or pops off the track. If you can see the best piece you can take pliers to try to gently guide it back into place
Your door will operate slowly with halting movements. Check your rollers to see that they are lubricated, can spin freely in their shafts, and don’t appear worn down or with chunks missing