ummmmmmmm, try getting a voltmeter, try it on the the power and disk drive led's, also, instead of using a vacuum cleaner, get one of those static-free , water-free, everything-free :-) air-in-a-can from computer stores, and then blow around the keyboard area including where you can under chips etc...
The keyboard also has its own processor, RAM, and ROM. It also has a selftest that performed on power up in the following sequence.
Performs a checksum on the ROM.
Checks the 64 bytes of keyboard RAM.
The timer is being tested
Performs a handshake with the computer and gives the result of the selftest.
If the keyboard does not pass the test, it will tell you through the blinking of the caps lock light.
One blink: Keyboard ROM check failed.
Two blinks: Keyboard RAM check failed.
Three blinks: Watch dog timer failure.
Four blinks: A short between two lines or the special control keys.
READ THIS (please). Don't panic if your keyboard flashes once when you switch on. THIS IS PERFECTLY NORMAL. Every Amiga in the entire universe does this.
check all that out :-D and give us more info
