tsum058cdt9-8 pinout

[Tony.T]

I have a circuitboard from a Dell Monitor SE2416H

https://www.ebay.com/itm/263828211518

Everytime it has been turned on for a while it starts to shut down and on automatically. if i use a hot gun on some areas it turns off DIRECTLY.  (bottom right area on the picture from the link above).

i have tried to measure the changes in that area when it turns off but cant see anything odd.  it is hard to only warm up a very small area and as i said, the board turns off and on also without having to much heat on it. During normal usage . Only when powering it up it takes maybe one minute or two until the problem starts. it turns off and on every maybe 30-60 seconds. If i warm up the mcu itself it will turn off and on but it is hard to say if it is the mcu or some other components.

i measured the ps on/off connector and DIM. on the connector top left. two lowest pins.   And can clearly see that dim clock stops before the shotdown. THen on off pin  goes low aswell.  After 10 seconds the clock (dim) starts again and monitor turns on again.  Those leads go to the MCU tsum058cdt9-8

I can not find any pinout of this MCU to see what part of the circuitboard has this overtemp protection circuit.  Is in built in and the only right thing is to change the MCU or is it another part of the circuit that somehow is involved and that needs to be replaced.

The PS works good and all the voltages are present. And as i said....o can change the frequency of the turning off and on by heating it. Does not matter if it turns on after its shutdown...as soon i put the heatgun...it shuts off. (normally it does that again after 30-60 seconds but if only 2 seconds and putting the heatgun it shuts down)

Any ideas here? Any help?  Would be appreciated a lot.