HP LaserJet 2600n Hidden Service Menu

During a troubleshooting session of a HP LaserJet 2600n printer I happened across a post on the official HP forums about a second level service menu. It's hidden away by default but you can access it by pressing the Green button, then the Left Arrow and Orange Cancel button at the same time, and finally the Green button again. This enables the Second Level Service option in the main menu. From here you can choose different calibration settings, additional reporting and higher level cleaning options.

While it didn't help solve my problem, from a support perspective it could prove to be very useful indeed.