Bill, have you tried pulling the battery, unplugging, and pressing the power button for 15 seconds or so to discharge?
Then plug in the battery, power, and the external keyboard and powerup.
If that fails, it could be a bad keyboard, but it could also be a jammed key. Look very carefully at each and every key and see if they are all in the up position.
This error could be a keyboard buffer overflow error which results from a key sending too many signals at post.
If all keys appear ok, I would remove the keyboard and add only the external keyboard.
To do this, release the latches at the top near the prtsc sys req key and the f2 key. You do this by pushing them up with a small screw driver...they are just spring loaded locks. They keyboard pops up after you move them out of the way.
You then need to slide the keyboard up about 1/8 inch toward the screen, then the keyboard will lif t out BUT, simply flip it over onto the hand rest. Now you need to remove the cable attaching the keyboard to the motherboard. carefully slide it off the pins--you will understand when you see it.
Now boot with just the external keyboard. if it works, they keyboard needs to be replaced.
Contact Sager (costs quite a bit. cannot recall how much.) You might also be able to acquire one in the For sale forum. I know one guy had one about 3 months ago from a machine he was parting out, but never sold the keyboard--I was going to buy it myself, but found one locally. He just had it in a drawer.
But try cleaning out the keyboard first...I find that people tend to each over their keyboards and things get jammed between the keys