Keysight U1271A Service Manual page 39

Calibration Procedures 1
If the four digits entered are correct, the display will show PASS. The calibration
security code is now set to its factory default code, 1234.
If the incorrect security code is entered, an error code will appear briefly, after
which the instrument will prompt you for the security code again.
If you want to enter a new security code, see "To change the calibration security
code" on page 37. Ensure that you record down the new security code.
Keysight U1270 Series Service Guide 39