We have recently upgraded to a excellent Element console from an Expression 3.
We intend to keep the Exp 3 as a back up.
The only fault it has is some of the keys are not registering when pushed.
I know the caps pop off, is there a way of cleaning the innards and what solvent/cleaner should be used.
Another repair tech and I will use rubbing alcohol to clean key contacts. There's no good way to get into the switch, so put a little rubbing alcohol in the contacts and press the key a few times, and it may loosen up the contacts. Just be sure the console is off when you do this, and allow time for it to dry before testing it out.
Does the key feel soft when pressed and doesn't click? If so, there is one method I use to get keys working again on our loaner stock: press the key hard until it clicks. Oddly enough, this works pretty well. The contacts seem to seize up over time if they're not used. I've even had new bump boards and new bump switches do this. Once the seize is broken, the key usually works again for quite awhile. I will say, though, make sure the screws are all tightened and installed on the board if you try this method, because it is going to flex the board a little.
Now, if the key clicks, but doesn't register, the problem may be a bad switch, or there may be a deeper issue.