Hi

I am facing unique problem. I have a Dell Latitude D505 which used to work fine till last week. Since then it give wierd problem

1. it does not boot when Main batterry is inserted.
2. If the battery is taken out, then it can boot on the Secondary battery or AC supply
3. after starting the machine, if I insert battery the system hangs.
4. Secondary battery does not get recharged when inserted in the laptop.

How can I fix the problem?

this situation tells us, that your battery is dead. the explanation is: most likely the bq8020 isn't responding via SMbus, so the KBC hangs up and the notebook hangs up too. however you can apply a "theurapetic methods" like update your bios and EC/KBC firmware. of course you sholud do that actions WITHOUT main battery. 10% chance that it will helps.