Code 14770: [Channel %1: ] Block %2 auxiliary function programmed incorrectly
Issue Description & Safety Warning
The Siemens SINUMERIK 840D CNC has triggered a critical [Channel %1: ] Block %2 auxiliary function programmed incorrectly alarm. Immediate attention from a qualified operator or maintenance technician is required to prevent secondary damage to the equipment or spoiled parts during the manufacturing cycle. Always ensure standard safety and LOTO procedures are followed before accessing electrical cabinets.
Official Troubleshooting Steps
Parameters: %1 = Channel number %2 = Block number, label Definitions: The permissible number of progra mmed auxiliary functions per NC block has been exceeded or more than one auxiliary function of the same auxiliar y function group has been programmed (M and S function). In the user-defined auxiliary functions, the maximu m number of auxiliary functions per group in the NCK system settings has been defined for all auxiliary functions by means of the MD11100 $MN_AUXFU_MAXNUM_GROUP_ASSIGN (default: 1) For each user-defined auxiliary f unction to be assigned to a group, the assignment is effected through 4 channel-specific machine data. Return jump from asynchronous subprogram with M 02/M17/M30, whereby the M code is not alone in the block. This is impermissible if the asynch ronous subprogram interrupts a block with WAITE, WAITM or WAITMC. Remedy: Program M02/M17/ M30 alone in the block or replace via RET. 22010 AUXFU_ASSIGN_TYPE: type of auxiliary function, e.g. M 22000 AUXFU_ASSIGN_GROUP: required group 22020 AUXFU_ASSIGN_EXTENSION: any required extension 22030 AUXFU_ASSIGN_VALUE: function value Reaction: Correction block is reorganized. Interface signals are set. Alarm display. Remedy: Correct the part program - max. 16 auxiliary functi ons, max. 5 M functions per NC block, max. 1 auxiliary function per group. Program Continuation: Clear alarm with NC ST ART or RESET key and continue the program.
Source: SINUMERIK 840D sl / 840Di sl / SINAMICS S120 Diagnostics Manual (DAsl, 03/2009)
Last reviewed: 2026-07-01 · Verified against the manufacturer’s official documentation.
About Siemens SINUMERIK 840D CNC Alarms
Siemens controllers include extensive self-diagnostics that flag or halt the machine when a fault is detected. Error code 14770 on the SINUMERIK 840D CNC identifies one specific fault condition — its documented cause and the official corrective steps are listed above, sourced from Siemens's service documentation. Always confirm against the manual for your exact machine configuration and follow LOTO procedures before servicing.
Complete Alarm List: 4014 Siemens SINUMERIK 840D CNC codes.
Have a better solution?
Help the industrial community by sharing your repair experience for code 14770.
Need a searchable reference for more Siemens SINUMERIK 840D CNC manuals?
We structure equipment manuals into searchable code, title, cause, solution, safety note, and source-reference data. Send a PDF and example searched codes when you need public pages, private search, or structured exports.
Space reserved for Google AdSense / Industrial Affiliate Links
Monetization target for 2026