Temperature Spikes when G28 used, CoreXY

Hey guys,

I've recently converted a Creatr machine to a CoreXY and am currently battling a temperature spike issue with the heated bed thermistor.
The electronics are a Arduino Mega 2560 with a Ramps 1.4 board driving dedicated stepper motor drivers.


When the machine is being homed in the X, Y and/or Z the bed temperature spikes up


This issue is also present when the machine is off and only the controller(ramps+arduino) is on. The issue goes away when the "corexy" is commented out in the firmware.

I've temporarily replaced the bed thermistor with a 5k resistor, but the spike issue still persists which makes me think that it's a firmware issue and not that the thermistor is acting up.

Is there anything I missed in setting up with the firmware for a corexy printer? I attached the two files that i made changes to(Configuration and pins_RAMPS.h)
pins_RAMPS.hConfiguration.h

Any help will be appreciated, as I've been stuck on this for over a week now.