Hi Eric (@emfritz ),
Many thanks for the extra info and detective work. It does indeed sound like you’re having the same issue as our other customer…
Please get the unit back to us. We’ll test it, swap the diode out, retest (!) and get it back to you.
The diode is the PESD0402-140 from Littelfuse. 0402 is the package size (yeah, sorry, I need magnifiers too!). 140 is the operating voltage: 14V (14 * 10^0). It is the right part for the job. In your case, maybe ESD has caused it to fail? But I’m guessing. Please get it back to us and we’ll take it from there.
Thanks for your support - and apologies for the inconvenience,
Paul