How old is the device? Is it set to temp? Are your coils temp controlled (nickle, titanium, stainless steel) or are they kanthal? Has the device suffered any damage? (i know its showing a high temp and sounds like its saying the device itself is too hot but sometimes the coil settings can be to blame for the error)
Sometimes devices get switched to temp control and they do not register that the coil is not a temp controlled coil and they immediately show a high temp warning upon you trying to fire the device, switching out of the temp mode could help. Also if it is in temp mode the temp could be too low and that could flag the high temp message.
If however this is not the case and no damage has been done to the device by you, or the device is new, then I would say the chip could likely be faulty. Older devices can start to fail as well so if it has some miles then it's a sign that the chip is probably giving out, I've warn down a few in my time vaping.
I hope that helps some.