For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
well this case left me unsolved but I'll be waiting if another one arrives, deliver the equipment like this.
I reflowed the lcd connector on the motherboard, I think maybe one of the pins was not making contact, I would have changed it. But good for next time. Thanks for your help @2informaticos
In my case as well, the voltages are 1.8 V and the resistance values are correct.
I have two MacBook A1932 units, and I replaced the mainboards in both of them. After that, the ALS sensor no longer worked.
I have now found out that the 2018 and 2019 versions are not compatible with each other. For example, if a 2019 mainboard is installed in a 2018 device, the ALS sensor no longer works. As a result, there is no keyboard backlight and no automatic display brightness adjustment.
The same applies the other way around: if a 2018 mainboard is installed in a 2019 device, the ALS sensor also does not work.
I just wanted to add this information here in the thread in case someone else runs into the same problem in the future.