Redondo Beach, CA
Quoted from Kodiak:So the left ramp will not register a shot when the advance raft is lit or meg millions. So it makes the game unplayable because you can not advance down the river. We replaced the CPU and that did nothing. We are ordering a new ASIC chip. All of the switch tests work. Driving us crazy.
Sounds like a bad diode or a short in that row of the switch matrix to me. Go into the switch test and hit every switch in the game. I bet some do nothing and others show multiple switches being triggered when a single switch is hit. Make a copy of the switch matrix and circle every switch giving you problems and then check the problem switches out very closely. Do a diode test on all the questionable switches. 
