Powerbook 100 detecting Low Level battery

[bibilit]

I have cleaned and replace caps, repaired the hard drive, the 100 boots ok and works fine, but once the desktop is present i have a message saying the battery is low and after a very short period the Powerbook turns itself down.

Of course, the battery is dead as a dodo, the powerbook is only working with the freshly repaired PSU, so something is detected as a low battery.

I have tried with two different hard drives, played with the small switch in the back, and the fuse is ok...

Any help ?

 

[techknight]

Do you have good stable voltage from the AC adapter? Thats important here. 

 

[bibilit]

The PSU was repaired (new caps around) and was stable a couple of weeks ago when tested with a Powerbook 145, but again you are right, i didn't tested it before firing the 100.

I will have a look and let you know.

If it's not the PSU, any idea here ?

 

[techknight]

Broken/rotten trace somewhere that was missed. Probably one of the control lines from the power supply section back to the PMU to tell the PMU is in charge/battery mode, and the ADC levels. All come from the main power supply circuit area. I believe the PMU chip itself is the same as the portable, so I know those 2 signals exist there. 

 

[nvdeynde]

Are you using it with the old battery installed ? If so remove it and set the battery switch at the backside in the down position.

I have had this issue with one of my PB100's.
I removed the 2 copper contacts in the housing that connect to the battery and then there's a switch with a small lever in the battery bay that detects if there's a battery installed or not. I just removed the metal clip of this one and it was sorted

 

[bibilit]

I will have a look, was tested with and without battery, maybe the switch detecting the battery is faulty...