PowerBook G3 Wallstreet/PDQ flaky power input jack

[mac27]

Howdy folks, I could use another set of eyes on this PBG3 power board issue:

I recently picked up a PowerBook G3 that works but has a flaky power connection at the DC input jack. The power connector has to be pushed and held in HARD for the machine to get power; as long as it's held like this it works fine. The instant you let go, the power drops out.

So I am suspecting a problem at the power jack, which resides on the power + sound board:

Upon initial inspection it appeared that one of the silver pins (legs) on the sides of the jack was not soldered at all (??). The jack also felt slightly loose when being wiggled. So I re-soldered this in an attempt to fix the connection.

Photos showing how I originally found it:

Photos after re-soldering this side (I am not a very good solderer):

So the jack is now soldered on both sides, and is also no longer loose - but unfortunately the issue persists (no change).

I am wondering if the issue might actually be related to these gold-colored legs on the rear of the jack. If they are also part of the connection, maybe their flat bottomsides are not making good contact with the board? This would make sense as the jack would be tilted back slightly when pressing hard, pushing these closer to the PCB.

If anyone has experience with this sort of issue or ideas regarding how to fix/troubleshoot further, would be much appreciated.

Replacement boards seem to be readily available online but I'd rather fix the one I already have if possible.

 

[alectrona6400]

i think somewhere someone had a similar issue with the pdq's charging board and it was fixed by replacing a ceramic/mlcc capacitor: https://tvc-16.science/wallstreet-pram-replacement.html
perhaps this might need a replacement

 

[mac27]

Thanks for the link. It seems that this person had problems more to do with sound and display, rather than with getting the power jack to make the connection. But it is also good to see some documentation regarding the construction of a new PRAM battery, anyways.

The fact that it takes physical force to fix/connect the power on my unit makes me think that there is something physically wrong with the connection(s) on the jack/board somewhere, rather than a component that's gone bad...

 

[alectrona6400]

ohhh, right. i mean, a dead PRAM battery in a wallstreet powerbook is kinda painful. the system will start for a moment and then shut off, then it will turn on after it takes its time to do the memory test of course. i would check your soldering joints of course, and perhaps clean up the jack with some 99% isopropyl alcohol.

 

[Kai Robinson]

Howdy folks, I could use another set of eyes on this PBG3 power board issue:

I recently picked up a PowerBook G3 that works but has a flaky power connection at the DC input jack. The power connector has to be pushed and held in HARD for the machine to get power; as long as it's held like this it works fine. The instant you let go, the power drops out.

So I am suspecting a problem at the power jack, which resides on the power + sound board:

View attachment 19215 View attachment 19216

Upon initial inspection it appeared that one of the silver pins (legs) on the sides of the jack was not soldered at all (??). The jack also felt slightly loose when being wiggled. So I re-soldered this in an attempt to fix the connection.

Photos showing how I originally found it:

View attachment 19219 View attachment 19220

Photos after re-soldering this side (I am not a very good solderer):

View attachment 19221

So the jack is now soldered on both sides, and is also no longer loose - but unfortunately the issue persists (no change).

I am wondering if the issue might actually be related to these gold-colored legs on the rear of the jack. If they are also part of the connection, maybe their flat bottomsides are not making good contact with the board? This would make sense as the jack would be tilted back slightly when pressing hard, pushing these closer to the PCB.

View attachment 19222

If anyone has experience with this sort of issue or ideas regarding how to fix/troubleshoot further, would be much appreciated.

Replacement boards seem to be readily available online but I'd rather fix the one I already have if possible.

Take a look at the MLCC under the word 'SINGAPORE' - cracked/dry solder on those fillets. I'd add a dab of flux and reflow each side, to be sure.

 

[mac27]

Take a look at the MLCC under the word 'SINGAPORE' - cracked/dry solder on those fillets. I'd add a dab of flux and reflow each side, to be sure.

Thanks for the tip - after reflowing the connections on both this MLCC and also on both sides of the power jack, the condition has improved some but a degree of wiggling/coercion is still required. Could just be my lackluster soldering skills and equipment. I've got a tested-working replacement board on the way for a hopefully better solution.

 

[JDW]

I'm watching this thread with interest because I too a PDQ (Pretty Darned Quirky) and it has power-on issues too.

 

[mac27]

Some good news - got the new (used) DC power / sound board installed, and that took care of this issue. No longer have to apply sideways and/or vertical pressure to the input jack. Success!

Link to the seller/listing I used for this part: https://www.ebay.com/itm/396093134707

"New" (top) and original (bottom) DC power / sound boards

Happy PDQ!

 

[JDW]

@mac27
So if it wasn't bad soldering of the power connector on your previous DC power board, then it must have been a fried component on it. Very interesting.

 

[mac27]

@mac27
So if it wasn't bad soldering of the power connector on your previous DC power board, then it must have been a fried component on it. Very interesting.

I'm inclined to think that it was something physically wrong with either the solder or maybe some other connection(s) somewhere on the board, as once you applied pressure at certain angles it did send power through and the computer worked fairly normally. But it was just not possible/realistic to hold that much pressure for that long if you actually wanted to use the laptop.

It would seem to me like a fried component would lead to a consistent no-power condition or the like, all the time, regardless of physical pressure applied.

 

[JDW]

I'm inclined to think that it was something physically wrong with either the solder or maybe some other connection(s) somewhere on the board...

I just wanted to reconfirm because in your opening post you mentioned having applied solder to the connector, but now you feel you cannot rule out the fact that the solder you applied wasn't perfect. In other words, it could be soldering of that connector, or it could be a "questionable" component. But it seems like you are leaning toward the soldering a bit more.

I am just curious and have been following this thread because I have my own PDQ with similar issues.

Anyway, thank your sharing the details, and I am overjoyed to hear yours is now fixed!

 

[mac27]

I just wanted to reconfirm because in your opening post you mentioned having applied solder to the connector, but now you feel you cannot rule out the fact that the solder you applied wasn't perfect. In other words, it could be soldering of that connector, or it could be a "questionable" component. But it seems like you are leaning toward the soldering a bit more.

I am just curious and have been following this thread because I have my own PDQ with similar issues.

Anyway, thank your sharing the details, and I am overjoyed to hear yours is now fixed!

Yes, that is correct. If yours is suffering from a similar intermittent-power issue and you're better at soldering than me then maybe you could fix it! Luckily this board comes right out without removal of the mobo (although it does require near-total disassembly anyways). Cheers!