With the A Ten unit we generally feel it’s the unit itself. Check the grounds to pumps, and for power coming out of the unit. Early models had an EPROM setup, later models thermals. The thermals were more KISS and not as hard to tech. If there’s no power coming out of an older dash, try wiring a test light or something that burns power, as they turn off when there is a failure in the feed that doesn’t meet the programmed power (amp) requirements, which have we believe an 8 amp maximum drain.