Al: Hi!

I quickly searched the ST4000 Operating & Installation manuals
available on the Net. V interesting. Looks like the firmware has
changed over time. Not all ST4000s have dealer calibration mode. And
the procedures for accessing Compass Calibration differ too.

Do you have the paper O & I manual for your ST4000 unit?

If not a quick search of the net should show at least three versions
(not all in English) with minor differences due to those changes in
firmware.

Those minor differences include differences in accessing the
calibration modes. Those differences render my earlier post useless.

In some versions, to get to compass calibration mode you need to press
and hold Standby for 2 seconds (to see the firmware version number),
then press Disp to work through the compass calibration routines
(heading alignment and vessel swinging). And in those versions,
standard user calibration has a three-fold entry process that involves
(1) pressing and holding Standby for 2 seconds, then (2) pressing and
holding Standby for 4 seconds; and finally (3) pressing and holding
Standby for 14 seconds.

Perhaps no one can offer generic instructions to cover all ST4000
versions? You might need the O & I manual for your specific firmware
version?

Cheers