• Cockpit Overhead Panel: Installed - SNAPSHOT- switch ASC255DSI on overhead panel in the spare vacant position adjacent to APU fire test switch. Comucted ASC2.55XDSI switch tin wiring as follows: Pint...are FD9030A22N to ground block E2 pin W; in 2 wire FD90213A22 to 318A1P7 pin small U; no why Jumper 22 to Pin