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My device is Rockstock Max v2, software using Repetier Host v1.0.6
After connecting and switching on the machine, the hot bed temp control icon disappeared in the manual control window. During the last few sessions of operations using previous version(with temp control icon appearing), the hot bed temp can never reach 110 degree C after turning on for over an hour. I wonder if this is a hardware problem or not. Can anyone tell me how to diagnose this problem?
I have pulled out the board and check the voltage of terminals, Heat 1 has 12V but heat 2 has no reading. However there is 12V reading from the black and yellow wires directly from the power supply.

The problem when trying to achieve such high heat on the bed is normally the stock power supply.
It just does not have enough current capacity to heat the bed to the higher temperatures.
There are many threads on this forum about the inability of the hot bed to reach temperature and the majority were
solved by replacing the stock power supply with a higher wattage power supply.