If those two switches are on the planet ramp, it may be the same issue that I had. I got the error when I put in a newer ROM chip to get the balls to lock around the planet. That is when I learned that two switches changed locations and numbers after the very early production games. I swapped back to the original ROM and the errors went away. All I had to do was install the planet ring with the holes instead of the slots for the balls and the ROM that came with the pin already supported the locking.