HP17BII will not power on

[burkhard]

Just the other night, I had something similar with a 32SII, also in the Pioneer series, so likely similar electrical architecture.

The calculator worked fine, but the display seemed a little low in contrast, so I popped the three LR44 batteries out and installed three new ones. Nothing. It wouldn't turn on.
So I took those out, checked their open-circuit voltage and all were OK. I checked the old ones and they were only marginally less. I put the old ones back *knowing* it had worked just a couple of minutes earlier on them, but still no good... no response at all to ON or any other key.

I had heard that sometimes (on Voyagers at least), they go "dead" and it's necessary to take the batteries out and jumper briefly (a second or so, not critical) the + and – terminal in the battery compartment, which discharges an internal capacitor. I never had to do that myself, but apparently others have. A wire would work, or a paper clip. I spread open a pair of metal tweezers that were handy to span between the contacts.

I gave that a try on my 32SII and voilà, it fired right up!

So, give that a try.