HP42S power-on issue


I have a new (for me) 42s. It seems to have an issue relating to turning on. Here is what happens.

- If it has been off for a while and I turn it on a message of "machine reset" appears on the screen.

- It can then be cycled off and on a few times without this happening, but eventually it will happen again even if it has not been off for very long.

- Then at some point it will not turn on again for some time. I'll come back to it several minutes later and it will turn on -- again with the "machine reset" message.

I could live with the machine reset, but it is a problem for it not to turn on at all sometimes.

I have removed the batteries. I have shorted the battery contacts for a few seconds.

Any thoughts? Can this be corrected? Do you think it is leading to complete failure of the unit?


You might want to take a look at this link:

Help with HP-42S

I have one with the same issue, it also BEEPS. I hope this helps.


I did see this before posting. The unit has new batteries and I did short the battery contacts.

The unit passes self-test and it does not beep when turned on.

Only issue is it does not always turn on and when it does it is sometimes with a "machine reset" message. But this usually occurs only after it has been off for some time (several minutes).

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