HP48 won't turn on (nothing on display)

[JDW]

I've been mulling the purchase of an HP-48 and found an SX which the seller says won't turn on. I instructed him to try the following:

1. Leave the batteries out for 48 hours then insert them and see if it powers on.

2. Reset by removing the upper right rubber foot, as viewed from the back side. You'll see a small hole with the letter R next to it. Insert a paper-clip as far as it will go, and release.

3. Press ON, hold down A, press and release F, release A, then release ON.

They performed all the above tests but still nothing will appear on the display. Is this truly a dead unit? If so, considering the appearance is pristine, what could be wrong with it? (In other words, is it easily fixable, do you think?)

Thanks.

[rprosperi]

(07-04-2016 12:03 AM)JDW Wrote:  I've been mulling the purchase of an HP-48 and found an SX which the seller says won't turn on. I instructed him to try the following:

1. Leave the batteries out for 48 hours then insert them and see if it powers on.

2. Reset by removing the upper right rubber foot, as viewed from the back side. You'll see a small hole with the letter R next to it. Insert a paper-clip as far as it will go, and release.

3. Press ON, hold down A, press and release F, release A, then release ON.

They performed all the above tests but still nothing will appear on the display. Is this truly a dead unit? If so, considering the appearance is pristine, what could be wrong with it? (In other words, is it easily fixable, do you think?)

Thanks.

Try pressing down on the area below the LCD but above the keyboard, while turning-on; this may work, and if so, it will be necessary to press down on that area while using many keys along the edge of the machine.

There is a common problem with older 48 machines where the foam used internally to maintain pressure on a keyboard connector has worn/dried-out. This can be repaired by opening the machine and replacing the foam, and usually everything else is fine. Assuming this is the problem, you can find instructions on how to open a 48 case in many places, including several here in the archives.

Adam Jones here on the forum (aj04062) can do this 48 keyboard repair if you aren't handy or if you want the machine to appear untouched after the repair.

All that said, why not get a 48GX? Many folks like the color-scheme of the SX better, but the GX has unquestionably better f/w.

My solution was to get both.

[JDW]

(07-04-2016 12:55 AM)rprosperi Wrote:  Try pressing down on the area below the LCD but above the keyboard, while turning-on; this may work...

The "pressing down" trick didn't work, so I ended up not making the purchase. Not sure what could be wrong with it, as it looks pristine!

Thanks for your help.