Code 206262: <location>Infeed: Temperature switch in the line filter open when powering up
Issue Description & Safety Warning
The Siemens SINUMERIK 840D CNC has triggered a critical <location>Infeed: Temperature switch in the line filter open when powering up 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
Message value: Drive object: A_INF, S_INF Reaction: OFF2 (OFF1) Acknowledge: IMMEDIATELY Cause: When powering up the infeed, the temperature in the line filter is too high. Powering up is prevented. Remedy: - check whether the line filter type set in p0220[0] ma tches the line filter that is actually connected. Ensure that the line filter specified for the inf eed being used is connected or correct the setting of the line filter type in P0220[0]. - temperature monitoring is mandatory for AIM line filt ers (refer to P0220). Ensure that the line filter temperature switch is correctly and reliably connected to input X21 of the infeed. - the filter temperature is too hi gh. Allow the system to cool down. - the internal fan of the filter module is defective. If required, replace the fan. - defective temperature switch of the filter module. If required, replace the filter module. SINAMICS-Alarms Diagnostics Manual (DAsl), 03/2009
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 206262 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 206262.
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