Small resistance between 5V and GND normal?

[giZmo350]

After you hear the short beep, try reversing the leads of your DVM and recheck the circuit for continuity. Do you hear another short beep? If so, you are charging and discharging a capacitor in the circuit with the battery in the DVM. Check schematic, there's probably a cap in the circuit somewhere. So, that would be normal.

As far as malfunction, not sure.

[giZmo350]

I tried and yes, that's exactly what happens if I invert and test again, and again, and again... I can spend all day hearing those short beeps hehe

Mesmerizing, ain't it! :laugh1:

About the cap... there are many caps that sit between 5V and GND, decoupling caps I think they are, so ok, If that's expected then I'll need to continue searching somewhere else for the trapdoor issue.

1 cap, many caps.... doesn't mater. What that tells you is that you don't have a short anywhere between the two points you had your leads on. That's a good thing.

This machine had an A501 whose battery went mad and the acid affected even the motherboard, so I think chances are high some trace or component got damaged, hopefully I'll find the problem soon.

BINGO! You'll find it! Schematics are your friend.

[giZmo350]

Glad I could help but you did all the work! Good job!