Nozzle temp showing 0 on 1.2mm head

So I’ve sent this to support and got the standard uninstall reinstall cura response, my hs 1.2 head worked perfectly for a while I changed back to the standard 0.5 head for some smaller detail prints. I’ve changed the heads a couple of times and the 1.2 head was sometimes showing 0 on the nozzle, I’d unplug it and replug it in and the issue disappeared, however 2 days ago I plugged it in and now it constantly shows 0 and won’t do anything. Does anyone have any ideas? Support have not replied (clearly to dodge replacing a £500 print head) the standard head works fine shows nozzle temp and prints. This is on a taz workhorse

If I had this problem, I would look very carefully at the wires close to the connector and the pins themselves. A loose crimp of the pins on the (thermistor) wires could act this way.