Hi @gachaz
Does it indicate that is is charging when you just plug in the charger and switch the charger on only?
Here’s a [https://www.youtube.com/watch?v=G5FpTkQ52ro|video] that shows how to solve starting ( and non starting) problems for an Asus Zenpad C 7.0
If that doesn’t work and it only starts when the charger is connected perhaps there is a problem with the battery and / or Power button and it (or they) need to be replaced.
Here’s a [https://www.youtube.com/watch?v=3ivSHyE6Fo8|video] that shows how to dis-assemble the tablet so that access to the battery is possible.
As there are at least 6 different Zenpad C 7 models and they don’t all use the same battery you will need to search online using the full model number of the tablet to see if there are suppliers of a replacement. Alternatively the part number should be printed on the battery in your tablet, so use that number to search for suppliers.
ZenPad C 7 Z170C (P01Z)
ZenPad C 7 Z170CG (P01Y)
ZenPad C 7 Z170MG
ZenPad C 7 Z171KG
ZenPad C 7 Z7010C
ZenPad C 7 Z7010CG
If the Power button is faulty i.e. intermittent in its’ operation, it is part of the Power and Volume Buttons flex cable. Search online for ''Asus Zenpad C 7.0 (insert model number) Power and Volume Buttons'' flex cable to find suppliers