Upgraded Firmware 3.2.3 Selftest fails on hotend  

Upgraded Firmware 3.2.3 Selftest fails on hotend

Hi,

Just upgraded my MK2/S to MK2.5/s, no problems (other than occasionally) the infamous thermal runaway.. 

My question here, I had a old MK1 sitting unused, and mounted the now unused MK2 heatbed and the MK2 extruder including the pinda.  Downloaded the 3.2.3 firmware. Using the MK2 configuration file, I adjusted steps pr axis, extrusion rate and motor currents to match the MK1 hardware. The file compiles and uploads correctly. 

However it refuses to preheat or pass the hotend part of the selftest. Doing a PID tuning heats up the hotend. It's possible to heat up the hotend via Octopi, but not the heatbed.  Did adapt, compile and uploaded a TH3D marlin firmware configuration, no problem to both heat the bed and the hot end, thus its wired correctly and the thermistors working. (miniRambo pin definition seems to be the same in both)

Now what it that I'm missing to get the Prusa 3.2.3 firmware to work on the bastard MK1? 

Thanks! Morten