How to remove components

I have removed some components from the schematic using Delete. Nevertheless, they still appear in the Symbol Fields Table, and, probably for that reason, cause error messages such as Duplicate Items in Annotation. The right-click Delete does not work in the Symbol Fields Table. What is the correct way to delete components?

Are you talking about deleting a symbol from the schematic?

You should just delete the symbol, either with the delete key or the right click context menu.

If the symbol still appears in the symbol fields table after that, I’m not sure. This is just a guess but do you have multi-unit symbols (U1A, U1B, etc) and you’ve only deleted one of the units?

Posting your schematic would be helpful.

Yes, this is with dual op-amps. I had to edit manually the U#'s because the Annotation tool connected my amps across chips, and not on same chip. That’s when it started. - A lot of confidential info in the schematic, let’s try to do without. Now the symbol fields table has two U4’s, but the schematic only has one. So, how to clean up the table?

Are you sure you have cleaned up all the U4 units such that you have a single U4A, U4B, and U4C? Don’t forget the VCC/VEE unit!

You can use ctrl-F to double check that you haven’t forgotten any U4s.

I did remove all U4 units, A, B and C. Then I replaced them. No change. Somehow, U4C assumes a zombie existence. Annotation says Duplicate Items U4C.

Ctrl-F doesn’t show any U4Cs you aren’t expecting?

If you reannotate with the “reset existing annotations” setting checked, does it still complain? Maybe back up before you do this.

Also, is this v6 or another version?

I checked with ctrl-F. Only U4A, U4B, U4C visible - the ones that should be there. I would like to show the symbol fields table, but copy-paste does not work, nor does clipping tool. I tried reannotations all conceivable ways, no change. I also tried closing and restarting KiCAD, no change. I have V6.0.2. Reset existing annotations I have tried - but then I have to re-edit the U#'s, and I’m back to square 1.

Hmm. I don’t know what else to suggest without looking at your project.

You could try making a copy of the project and deleting bits until you’re left with just U4 or the problem goes away, whichever comes first.

You could also try updating to 6.0.8 and see if there was a bug that was fixed sometime in the last 6 months in that area.

Thanks a lot for your help. I think I’ll do the upgrade tomorrow morning and see what happens. Of course, I always have the option to rebuild from scratch.

Clicking on the Reference column in the Symbols Fields Table should pan to and highlight the schematic symbol to which that line corresponds. Pressing Delete to remove schematic symbols from the schematic is the normal way to remove parts from the schematic, and the Symbol Fields Table should always reflect that.

There should never be entries in the Symbol Fields Table which are not on the schematic. One of the “extra” tools you can use is to open the schematic in a text editor to search for strings. The saved version you see in the text editor can of course easily differ from the active / opened schematic in KiCad. Don’t make changes to the file with the text editor, especially when KiCad is open, but you can use it to search for strings.

Maybe there is something weird about that particular op amp symbol. One idea: Make a copy of your entire project folder to minimize risk if you prefer. Then try adding some other dual op amp or other dual device. Then save everything, then delete it and see if you have the same problem.

From where did you get 6.0.2?
From where did you get the symbol?
What is your OS?

In actual fact, there are entries in the Symbol Fields Table that are not in the Schematic.

I got 6.0.2 from the usual place, The symbol came with it. I’m in Windows 10.

Can you find the reference designators of the offending parts in the schematic file with a text editor?

Can you make a copy of the project, then remove most of the schematic so your intellectual property is secure but the offending parts are still present and then post it here?

Some time ago there was a weird issue with someone else’s schematic. After some analysis it turned out that a small part of the schematic had coordinates approximately 11 meters to the right side of the screen, which had the result that part was never visible on the schematic, and therefore it could not be selected or removed from within KiCad.

With a text editor however, that part was quite easy to identify, and I removed the first two one’s from each of the X coordinates. This showed that block (a transistor, few resistors and wires) thereafter normally in the schematic. It looked like it was the remnant of some block copy operation gone awry.

Problem resolved, I think. I used Notepad to gain some understanding, and then I methodically deleted and reinstalled all duals I have. Apparently, some unit#'s and reference #'s were crossed. So, be careful if you have to edit the reference #'s. Maybe the error message could be more explicit? Thanks to everybody for your help.


Similar happened to me not so long ago… Do not really know what caused it, but I removed it with a text editor. A text editor is always available as a last resort with KiCad. Be sure to make a back up copy of everything before experimenting on KiCad files with a text editor.

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Kicad shouldnt allow two u4c’s in the first place.
If someone tried to rename to a already there U then it should flag an error.

I don’t think I agree. There are lots of things you should be able to do in transition from one state to another. ERC will report an error, but that doesn’t mean KiCad should prevent me from temporarily having two symbols with the same reference.

At some point the extra u4c will have to be deleted so why not stop it in the first place.
Its one less error to deal with.
Sometimes freedom with that sort of thing can create a right mess.