Power lites come on **** its black when you look threw the vewer

Year make and model would help. Sounds like a A wiring harness is rub threw. Check the black conduit from the switch back to the main harness.

Possible crankshaft sensor at fault. Find someone with a wave form vewer and check voltage and voltage flow and ground

what i would recommend is to turn power off to unit, turn water off, now open a hot tap inside. Go back to hw unit , turn power back on, now turn HW cold water tap to open. Now you should hear the unit start up.& click continuosly, this is the unit trying to lite. The unit has a flow sensor so as water passes threw it ,that tells unit when to lite. If you hear nothing & no water comming threw you strainer located above cold shut off tap is blocked, unscrew black knob & check. If you have flow & no HW check your gas, usally by losening gas union, there is also filter above this. Also plug another power tool into power point to check you have power

you can also use an ATX PSU by put a wire between green and black to switch the power on and put your died psu's wire into black and yellow plug (+ on yellow - on black)

Sounds like the processor has gone on the mainboard.
Using r4 or similar card? if so these burn out the board sometimes.

errr

Try removing the battery completely and powering it up on AC power. Sometimes a dead battery (even if you're plugged in to AC) will stall a boot-up in its tracks. If this doesn't help, please reply back and let me know if anything changed.

printer ane error prin color'nya g bisa

your screen is broken go to a electronic shop to buy a new top screen

it could be your oil pump or it threw a rod