Folding Mirrors

[Concept]

My folding mirrors have suddenly stopped folding.

All other functions work fine.

Any ideas on this?

Thanks

[doddski]

My folding mirrors work when they want to.
The passenger side rarely works - drivers side is much more likely to work.

They stopped working after I stopped folding them as much - living in a very dusty environment, I expect that they are so full of dust which why not working.
The drivers side works a lot better now - I did have to lightly encourage it a couple of times though.

I expect once cleaned and re greased all should be 100% fine for both sides