Am I missing any diagnosis steps for my Whisperflo Pump?

[cheezedawg]

One of my pumps quit working this week- might be related to the colder weather (temps have dipped into the upper 20's overnight), but I don't know. We don't get cold enough here to really warrant a full winterization- this is as cold as it gets. This is just a pump for the waterfall, so the rest of the pumps seem fine.

When I turn it on, I hear the relay click, but thats it. I dont hear any other noise. I haven't been able to get out to check it out any further yet, but what all should I check?

- I plan to probe the voltage at the pump using my multimeter to make sure the relay is working
- I can try swapping the capacitor with an identical Whisperflo pump that is still working (used for spa jets) to see if that is the problem
- I will try to spin the pump by hand to make sure its not a bearing or something, although it seems that it would make some sort of noise if that was the case
- What else?

 

[JVTrain]

Looks like you've got a good list to start with!

 

[cheezedawg]

Figured I should update this. I went out with my tools prepared to do battle, but it turned out that the GFCI had tripped on that circuit. So now I am mildly interested about why it tripped (pump is the only thing on that circuit and there were no obvious signs of water intrusion to places where water shouldn't be), but the pump is still working.