Allright, so after a lot of testing and research I got this answer on a reddit repair sub:
"On iPad Air 1st gens, there's two hall effect sensors for the smart cover. One is on the home button flex, the other is on the motherboard near the home button connector. The smart cover has two magnets in these locations and both sensors have to be triggered for the smart cover function to work. When wrapped around the back, the motherboard sensor will trigger, but the home button sensor should not. If the latter is faulty however, then the motherboard sensor will trigger it front or back.
I do see this a lot on replacement home button flexes or aftermarket where there's no sensor at all. I haven't scoped it out to see whether the logic level to trigger is active high or low, but it appears the faulty cables essentially indicate to the Air that a magnet is present all the time.
Now to test replacements, I connect the home button separately and leave it hanging out of the chassis. I use an external magnet near the motherboard sensor - if it triggers, the home button flex is deemed crook. If not, I then hold the home button sensor onto the magnet as well and bring the whole thing up to the motherboard sensor. If it switches all is well, if it doesn't switch the home button sensor is also deemed faulty.
As I said, I've seen this on aftermarket home button cables with no sensor at all. I need to buzz it out to see whether the Chinese have shorted out pin 3 or connected it to 3V."
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Following this we finally fixed the iPad Air locking issue by switching to another original home flex that we had lying around. Apparently they're easily damaged and needs to be transferred with care.
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Following this we finally fixed the iPad Air locking issue by switching to another original home flex that we had lying around, since the original one we had didn't work. Apparently they're easily damaged and needs to be transferred with care.
Allright, so after a lot of testing and research I got this answer on a reddit repair sub:
"On iPad Air 1st gens, there's two hall effect sensors for the smart cover. One is on the home button flex, the other is on the motherboard near the home button connector. The smart cover has two magnets in these locations and both sensors have to be triggered for the smart cover function to work. When wrapped around the back, the motherboard sensor will trigger, but the home button sensor should not. If the latter is faulty however, then the motherboard sensor will trigger it front or back.
I do see this a lot on replacement home button flexes or aftermarket where there's no sensor at all. I haven't scoped it out to see whether the logic level to trigger is active high or low, but it appears the faulty cables essentially indicate to the Air that a magnet is present all the time.
Now to test replacements, I connect the home button separately and leave it hanging out of the chassis. I use an external magnet near the motherboard sensor - if it triggers, the home button flex is deemed crook. If not, I then hold the home button sensor onto the magnet as well and bring the whole thing up to the motherboard sensor. If it switches all is well, if it doesn't switch the home button sensor is also deemed faulty.
As I said, I've seen this on aftermarket home button cables with no sensor at all. I need to buzz it out to see whether the Chinese have shorted out pin 3 or connected it to 3V."
Following this we finally fixed the iPad Air locking issue by switching to another original home flex that we had lying around. Apparently they're easily damaged and needs to be transferred with care.