Nexus 5X no "Charging rapidly" on original (stock) charger After 7 months LG Nexus 5X now doesn't show "Charging rapidly" but only "Charging".

Ampere app shows 1700 - 2100 mA max. Overall charging time now 50% longer than initially was.

In accordance to screenshots of Ampere I see the following wattage:

4.07V * 0.89A = 3.62W

or 

4.26V * 1.79A = 7.62W

Both measurements are far from 15W declared by Nexus 5X specs.

I have checked my original 5X charger with Nexus 6P phone - it displays "Charging rapidly" on 6P from my charger. This makes me to believe the issue with the phone or its battery or QC IC (Quick Charge integrated circuit).

Update: 


My charger is OK with Nexus 6P -> "Charging rapidly"
Nexus 6P charger doesn't detected on my 5X at all -> no charge, nothing
Switching cables on 6P charger with 6P phone -> 5X cable OK on 6P "Charging rapidly"


Conclusion: Phone Nexus 5X itself is suspected: battery or charger chip or system.
I had the same issue with my Nexus 6P. Tried everything but nothing worked. Visited service centre and got it fixed. They told some hardware issues with the fast charging chip.

 I read somewhere that flashing the firmware again using Fastboot on the phone solves this issue for some users.I didn't worked for me. Might you wanna try. Good Luck!!