Stuck on a board repair

Thread Starter


Joined May 30, 2022
Hello guys, I'm trying to repair this board and have found the problem but am struggling with the cause and solution.

Images here:
So, from what I have worked out, 12V input goes to the STM32100 circled in red. This chip is receiving power on all points and the only problem with this board is caused by 1 output on that chip, so I'm guessing it's not the chip.

The output signal from the pin (PA6) on the Stm chip then goes to the input of the next chip D5160J circled in yellow. This input pin is the switch for the output side, so one it receives a signal from the STM it will send the output voltage to the 4 pin connector above it.

It's not sending any signal though for some reason, im not sure if the STM chip is supposed to receive something on one of its inputs to then output its signal on PA6 so I'm stuck.

Does anyone have any advice please? What do I do next? What would you do here?


Joined Oct 2, 2009
For starters it would help if you told us the make, model and function of this unit.
Gas fired water heater for a swimming pool?