Ambient Light Sensor not working after LCD replacement
I've had the display (full upper case) replaced third party after I somehow managed to crack the LCD. My insurer's terms are you have to use a repairer company that they specify (and accidental damage is not covered by Applecare in the UK) which is not Apple Authorised, so they have to use refurb parts.
It's all good except for the light sensor. Shine a torch at it, cup your hand over it, nothing happens. I wouldn't mind so much as the display and keyboard can be manually adjusted, but unfortunately the touch bar cannot - it relies entirely on auto adjustment based on ambient light level. So it's always on full brightness, which is distracting in a low light environment.
I've tried the following:
NVRAM reset (several times)
SMC reset (several times)
Reinstalled the OS from scratch
And of course auto brightness is turned on.
Is there anything else I can try or is it just likely to be a duff sensor? I don't really want to send it back to the repairers if I can help it as it's a very slow process, it's been over 3 weeks turnaround and I'd probably be in for that timescale again.
The iSight camera works fine, and as I understand it the sensor is on the same board.