Portable won't run from battery

[timoog]

I've made a new battery for the portable, using a cylon 3 cell job. Simple to trim the sides and fit to the case. I had the same set up previously but the battery has died due to the time the portable was out of action.

Battery is charging (original power adaptor) holds a good ~6.5V but when I unplug the power cord the screen slowly fades and dies.

Any suggestions what to look for?

Thanks all!

 

[GRudolf94]

Has your machine been recapped and gone over? Normally these issues stem from capacitor damage. A faulty hybrid could also result in a machine not being able to run off battery.

 

[timoog]

Hi @GRudolf94, yes recapped last year. Maybe have to get the mb out and test the hybrid board. Thanks!

 

[alexGS]

In the non-backlit Portables, I’ve done three where replacing the hybrid made a huge improvement to turning on (without doing the little dance with the buttons on the side) and to battery charging, battery gauge when running, etc. The first one in particular, I replaced all the capacitors and it was still really flaky - as I lack the knowledge to diagnose the Hybrid properly, I highly recommend the replacement hybrid modules sold on eBay by ‘supersvga’ at what I think is a modest price.

I don’t find it easy to desolder all those pins at once, so I simply clipped them and removed pins individually. The first one below, I desoldered them off the Hybrid but that was difficult also as it was double-sided.

Either way, it seemed better not to risk damaging the through-holes in the main board. Maybe that was a bit rough of me to destroy the original Hybrid that way, but the end result with the new parts looks tidy.

 

[timoog]

Thanks alexGS, that's very encouraging. Good solution, was thinking solder wick and then heat gun, but there's a lot of bits that might go awol! Need to get a hybrid replacement first though

 

[alexGS]

Thanks alexGS, that's very encouraging. Good solution, was thinking solder wick and then heat gun, but there's a lot of bits that might go awol! Need to get a hybrid replacement first though

Yep, I had the same idea, draw away the solder with the solder wick, heat the whole thing with the SMD hot air tool, but I just couldn’t get all those pins moving at once, the holes in the logic board are small. I found it more difficult than removing, say, a 40-pin 6522 from an early Mac logic board. Maybe some people find it easier, but just letting you know the cheat way works too

To give full detail - first one I did by straightening all the pins on top of the Hybrid, then heating with the heat gun to pop the Hybrid free of the pins (they’re soldered on the bottom of the Hybrid), then used the soldering iron to heat and remove each pin from the logic board

 

[timoog]

Thanks @alexGS that's good detail

 

[Brooklyn]

Simple, but did you check the battery cover switch is working? The symptoms you describe could also be due to the portable running off the 9V battery when unplugged instead of the main battery.

 

[timoog]

Good shout Brooklyn, I checked it was sending current to the battery terminals when depressed so guess that would be working?

 

[timoog]

Done! new hybrid from Supesvga and now running happily from battery. Not easy to get out cleanly but took my time, had to chop the old one up but all ok. Big shout out to @SuperSVGA and @androda for their hardware projects for the portable

 

[desertrout]

Done! new hybrid from Supesvga and now running happily from battery. Not easy to get out cleanly but took my time, had to chop the old one up but all ok. Big shout out to @SuperSVGA and @androda for their hardware projects for the portable

Nice! I keep thinking I should get a hybrid replacement, even though my Portable actually runs pretty well... but battery usage is kinda dodgy - seems to drain quickly and charge inconsistently (it's one of those cheaper replacements, not sure that's part of the problem). Did you go through androda's test steps, or just swap it out?

 

[timoog]

I didn't, I had the new board to jumped right in to replace