Step 8: Repairing the Control Board: checking the Diodes

Picture of Repairing the Control Board: checking the Diodes
With the DMM still set to the Diode-check range, check each one of the large Power Diodes on the other side of the board (see pic) the following way: Connect the DMM probes to each end of the diode and look for an open circuit indication (no indication) or a diode indication (an indication of somewhere between 0.4 and 0.6). Then reverse the probes and check for the opposite indication to the one before. If any of the DMM readings indicate a short, or an open in both directions, the diode is faulty; and must be replaced. Check all power diodes. I never found any of the smaller diodes faulty, but if all else fails to repair the board, you will need to check these too. On the last repair, all four diodes in the bridge configuration feeding the electro caps had blown, all cracked open, and part of the PCB track had vaporized.
jasshrie5 months ago

I am in mid-troubleshoot mode on my GW712 and have only found the 4A fuse blown and vaporized PCB tracks as well. Is this repairable or must the board be replaced? Here is an image of the tracks below.

And the story of faults in brief: After failing to drain the tub, it threw the error code 37 (Pump Blocked Error). I tried to put it into spin mode a few times to drain the water and each time it would pump for about 15-20 seconds before stopping, and after a few min would throw the code. I noticed a faint burning smell. The final time I tried this, the LEDs on the control panel flashed and then went out. The machine was dead. I removed the pump and control panel, found no blockage in the pump, so far only the failed fuse and vaporized tracks on the PCB shown below.