Dead battery- what could it be?

[Gilles]

A month ago I parked my car at a friends house as I needed the space to work on a different vehicle and noticed that the battery struggled a bit to start the engine (2016CS with original battery..), the car was parked at her house for about two weeks but left the hood latch covered with a towel just in case.

Afterwards, I installed a new AGM battery and it ran great (starts the engine with much more power), however yesterday I plugged the Durametric to reset the oil service message and I noticed that I had a P1559 code on the engine module..

Could the P1559 code caused by the weak battery, and just needed to be cleared? Thank you!