I have some washing machine motor driver boards (Fisher & Paykel, 421389NAP and others like those) here. They all have rather obscure issues. I just found out that resistor values are all over the place, for example 200 kOhm resistors that are extremely consistently at 160 kOhm over >10 samples (100 % of tested) over 2 years of production. Same with other resistors (80 Ohm instead of 330, 80 kOhm instead of 100 kOhm). I can read the markings and will thus replace them, hoping that it will fix the obscure issues.
However, one resistor is unintelligible across all of the boards. I have 2 pictures of 2 different boards attached, one from 2005 and one from 2007. Take a look and have a guess. When measured out of circuit, one was reading something with a 2 at the front, I think it was ~2 kOhm. The 4 and 3 are very clearly readable. But the 3. digit is impossible to make out. An 8, which seems like the most likely number, makes zero sense, since that would be 4.3 GOhm. Has anyone every seen something like this? What could that be? Is it an R, so 43 Ohm? Other resistors on the boards use 0 instead of R to denote such values (at least above 10 Ohm), so that would seem to be inconsistent.
Also, any ideas how they can drift to such a degree? Or is that from production? Seeing such terrible silk screen makes it seem like a super low quality. However, all the caps on there are nichicon... so... jeah.