Shortly after buying my 2016 GTI I disabled the start/stop by changing the start/stop voltage limit in the Can gateway controller, the originally stored values is 7.6 I changed it to 12.1 per a guide I found somewhere ....
all is well for 2 yrs ...
I have a car parked 6 of the 7 days of the week and the battery needed to be charged , while charging the battery in the GTI while driving it I was monitoring the voltage and was surprised to see the following:
Idle and coasting voltage was 13.8V
Accelerating voltage was 12.2V (why so low ?)
GTI battery voltage 11.9V (this is way low and I fear I'll need a new battery very soon)
What the hell? Checked my wife's car battery and it was a healthy 12.6V , why is the GTI charging at such a low voltage when pressing the accelerator ? After thinking a bit I remembered the change in the voltage for the start/stop, so I reset it back to 7.6V
Drove again after the change, the voltages in the GTI were:
Idle and coasting voltage was 14.8V
Accelerating voltage was 13.7V
GTI battery voltage 12.2V , I hope it keeps recovering and lasts a little longer with normal charging voltages
This is just my opinion and I can't understand why changing the start stop voltage limit will affect the charging voltage or if my car or battery have a problem, but the difference was very clear, so, if you changed the voltage limit to disable the start stop, it would be nice if you can check your battery voltage , with the engine off it should be above 12.5V
and in the mean time I'll keep pressing the button to disable the start stop