Across the nation from southern California to the east Coast:
I have two Viking Designer SE machines, motherboards when out on both. My Viking dealer want $650 (each) to replace with 'used' motherboards (no warranty). Other dealers were even higher, and a new machine is too expensive.
After searching the Internet for 'how to repair' and after A LOT of prayer, I found 'The Sewing Machine Repair Guy' on YouTube (retired...worked as an electrician on nuclear submarine for 20+ years). Turns out, his wife also has a Designer SE; he replaced all the capacitors on the motherboards. He has videos on how to do this on YouTube, and sells kits on Etsy.
Cavaet...I took both my machines apart MYSELF, and shipped the motherboards to him (his suggestion as I do not have original packing to protect machines during shipping, nor does he.
He was able to replace all the capacitors on the motherboards for both machines for less than $175; they work beautifully...including the embroidery.
There were two special screwdrivers that I had to purchase and a wrist/static thingy (so I would not get shocked). Also, I watched his video on how to take the machines apart and replace the motherboards several times (including taking screen shots of each and every step and putting them into a PowerPoint presentation...also took a lot of photos with my phone while taking them apart.
https://www.youtube.com/@SewingMachi...h?query=Viking