SYMPTOM 1: Laptop shows no signs of life, no lights appear when power supply is plugged in with the main battery removed.
DIAGNOSIS: Either the internal or external power supply is faulty - check the obvious: a)fuse b)if you have a Volt meter - check the voltage output of any external PSU is correct & constant. If you find the ac working then you have an internal PSB (Power Supply Board) fault.
SYMPTOM 2: Laptop doesn't power on when the power button/switch is switched on - power led light lights up and not much else happens - screen does not light up.
DIAGNOSIS: Remove all removable devices such as: additional memory, battery, hard disk & try powering the system again.
