acer travelmate 2700 motherboard problem

I have a acer travelmate 2700
Symptoms include:

1. Operating laptop on power, with battery inserted - after a while, it
will revert to battery power. Won't recognise when the external power
plug is inserted, so eventually drains down the battery.

2. When 1 above occurs, if I shut down the system, the battery charging
indicator comes on and the battery recharges.

Currently it is shut down, external power on and battery inserted and
the battery led is flashing orange. Don't know what that means,

I'd appreciate any guidance on troubleshooting this further – I am pretty sure it’s a hardware (motherboard) problem
The problem has got worse now motherboard sounds like a ticking bomb ticking very fast

Thanks in advance for any feedback.