I'd say you have a max temp set too low in your host software. Earlier when you heated to 180 were you using RH? And then when you got the error of exactly 150 degrees were you using Simplify 3D?
My advice would be to use Slic3r and RH. Take the time to learn everything you can about setting up proper profiles. Remember there's a start code section in your slice profile and a start code section in RH as well. Use one or the other but not both. Ensure that all profile temps match, yes they can be in the start code so set them correctly or remove those lines and use the manual control.
Here's what I know for sure.
It's not the board or the firmware.
It's not the hot end, although your splices or the stock connectors leave little to be desired. They shouldn't be causing this issue. But may be worth double checking.
I am 95% certain you have a software setting issue.
Hope that helps.
Printit Industries Model 8.10 fully enclosed CoreXY, Chamber heat
3-SD3's & a Workbench all fully enclosed, RH-Slic3r Win7pro, E3D V6, Volcano & Cyclops Hot End
SSR/500W AC Heated Glass Bed, Linear bearings on SS rods. Direct Drive Y-axis, BulldogXL
Thanks to all for your contributions