The AC03 manual has a very simple troubleshooting tree. Here is the short version:
If you’ve just unboxed a Pramac AC03 (or picked one up second-hand), you might be staring at a control panel full of dials, sockets, and a mysterious pull cord. The "quick start" guide often leaves out the crucial details. pramac ac03 manual
After spending a weekend troubleshooting my own AC03, I realized that the Pramac AC03 manual isn't just a pamphlet—it’s the key to keeping this rugged little generator running for a decade. The AC03 manual has a very simple troubleshooting tree
Here is everything you need to know about finding, reading, and actually using the manual for the Pramac AC03. pramac ac03 manual
Page 12 of the manual is the most important.