If all else fails, try this:
Remove the ram. There is a spot labeld j4 under the ram. If you look closely its actually two pieces of metal very close to each other. Short them to a ground like the ram chasis with a paperclip or other conductor and start the computer while they're shorted wait 10 seconds, turn it off, put the ram back in and turn it on.
pulled both rams and no j4 any where to be found ?? Model A215-7437