The next likely bad part is the motherboard as you replaced the other parts. The DV6's I see are now over 4 years old and never repaired today.
I have a hp pavilion dv6. The AC adaptor was bad so I bought a new one along with a new battery. I put the new battery and the computer worked until that battery was dead. Now I have it plugged in and the indicator light comes on but the computer will not turn on. I've tried to unplug it take the battery out and hold down on the power button for 60 seconds and that didn't help. Can anyone help?

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