Ensoniq ESQ-1 dead key

I have just rediscovered a long disused ESQ-1 from parent’s basement. I have to change the battery, which seems pretty easy, but there’s another problem- it has a single dead key. I’m looking for ideas about things to try from an easy fix to more complicated causes so that I could at least try the easier ones and see what happens.


The easiest fix would be if there was a problem with the flexible spring under the affected key.
The hardest will be that you’ll have to remove the pcb from the keybed and check for continuity on the traces. Good luck with the repair.

Thanks, I wonder if the spring would be issue. The action of the key is fine, just no sound when pressed (I didn’t t make clear) your other suggestion may work I’ll update when I have chance to go in.

The key can feel fine, but if the very delicate contact spring is bent or just very dirty, it might not make contact. You’ll need to remove the keybed and give it a close look - this is almost certainly where the problem lies.