Norcold fridge doing on-off, on-off routine

Hi, all -

I have a Norcold fridge on my boat that's suddenly doing an on-off thing, running for about 2 seconds, off for about 4, then over again.

The basic question is whether or not this condition points to a specific problem. I'm pretty handy with tools, so if this indicates some electronic part is fried, I'll order the part and replace it myself. If it's low on freon (or whatever they're using these days), that'll require a service guy.

Any thoughts, gentlemen?

Thanks,
Eric