Older Style Key Maintenance
My key remote wasn't working very well any more so I tried a new battery (even though the battery checker said it was okay). And even tried holding it to my head.
But nothing helped. So I decided to take the key apart and clean out the insides. I just used a pencil eraser to clean up the gunk that had accumulated on the contacts on the plastic bubble sheet and on the transmitter unit. Now it works great. Take a look: