Triton shower intermittently heats & cools?

Hi my Triton Biarritz has been intermittently going from hot to cold, had a look, found cable from 1st thermal cut out to microswitch (leading to solenoid valve) heat damaged. Cable leading to 2nd cut out(sensing outflow) was heat damaged close to cut out, so replaced cables, now power amber light not coming on, water only becoming lukewarm at max positions for both dials. How to determine if cut out are the problem? is it possible amber neon is "blown?" plse help!