SiePortal

The integrated platform for your product selection, buying and support workflow - bringing together Industry Mall and Online Support.

Products & Services
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
Support Support
{{(apiData.Support | filter:{'rank':1}:true)[0].title}} Support
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
MySiePortal MySiePortal
{{(apiData.MySiePortal | filter:{'rank':1}:true)[0].title}} MySiePortal
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
Cart ({{apiData.CartCount}})

Navigation

S7-400 - EXTF

3/6/2025 2:19 PM	Rate (0)
AutoGen_4091511 Member Joined: 3/15/2017 Last visit: 6/18/2025 Posts: 1 Rating: (0)	Hi all, we have a Siemens 400 series PLC with EXTF permanently lit. The batteries are fine. We have tried clearing all OB blocks. The PLC continued to run normally, but the EXTF is still lit. There is also nothing in the diagnostic buffer. HW configuration reports no error. The profinet topology is also fine. Can you advise how to proceed in finding the cause ?

Suggestion To thank Quote Answer

3/6/2025 2:42 PM	Rate (0)
Towome Platinum Expert Joined: 7/9/2015 Last visit: 8/29/2025 Posts: 4443 Rating: (641)	Hi, did you check manual of you PLC? There you find further informations about Status and error displays Regards, Towome
	If my post was useful, please rate me - if not, please tell me - thank you!
Suggestion To thank Quote Answer