Front camera not working after several replacements

Hi there,

I have recently replaced the front camera assembly on an iPhone 5s because the auto brightness feature wasn't working.

However now the camera itself doesn't work.

I have tried resetting the phone, even putting it into DFU mode and updating to the latest iOS, and tried several different camera assemblies - all to no avail.

I can't see any damage at all to the pins on the motherboard where the flex cable attaches, is it still a possibility that this is damaged?

Or is there any other solution that I haven't thought of?

Is it worth disconnecting the battery to power cycle the phone?