RAMPS PLUS 2 and E1 socket problem (K200 Delta, but related to the PCB , not printer)

Hi

Total 3D printing newbie here, apoloies in advance if my terminology is wrong.

I have a dual head K200 delta printer with a heated bed which I put together 8 months ago, but gave up due to frustration of the following error in Repetier:

temp sensor defect marked defect
Errorrinter set into dry run mode until restart!

I've tried again today, and all 3 thermistors (and the spare) work fine, but socket E1 on the BT7200 V1.8.26 RAMPS PLUS 2 is giving me -20oC readings no matter which thermistor I put in.

Even though I’ve tried to tell it there’s only 1 extruder (in Printer Settings), the display right at the bottom of Repetier still thinks there’s 2.

I've emailed the seller and the company I bought it *through*, to see if they can help.

In the meantime - is there any way to change things so that I can use the heated bed socket for the other extruder instead and just try to make due without the heatbed for now?

Hope you can help.

Please don't triple post the same thread 'everywhere' in the forums.