swapped TZ touch

[Matt C]

the replacement plotter works but now the plotter at the helm won't turn on.

 

[Johnny Electron]

I guess this is a TZT14 or TZT9? If another unit that was working fine won't turn ON, then maybe the boat power system isn't up to powering two units and there is a lack of current. I would recommend using a power supply and test the unit(s) with known good power.