It took a long time to sort out because we had to wait for a motherboard to arrive but in the end a new motherboard cured it. Not great news but sharing an odd fix that went past the shop.
My Dell Inspiron 1545, not working properly. It boots only when you don't power up for few days. Once ON, then I need to wait few more days to turn it ON again. I started inspecting mother board. I have downloaded schematic from net. I found, the power section is not getting enabled. Ther is no 5V_ALW and 3P3V_ALW. The 18V from the adapter and 3.3V RTC and 5V VCC1 are stable.Help me to further debug the problem.