My car's generator is putting out 13.5 voltages when on full load (blower, ac, lights etc) but when i check the voltage on car's cigarette lighter port it it drops to even 11.6 when blower is on, when blower is not on they are between 12.8 to 13.0
My car's battery keeps dying every year because it keeps drying the water inside it.
This is how i think it is happening and correct me if i am wrong,
On battery terminals, voltages are 13.5 which is great and battery is charging and all.
But for some reason there is high resistance between the battery terminal and the wire that is coming inside the cabin to distribution box (which has fuses etc) and when 20amp blower run it drops the voltages to 11.8 or below.
But the main problem why battery is getting damaged is because inside the cabin voltages are 11.8 and of course the car's ECU is getting the voltage reading from inner distribution panel so because of that ECU gets 11.8 and it keeps the Alternator to keep charging battery because it suppose to stop charging when battery is at 12.6 which according to the inner distribution box it never happens.
I know somewhat voltages are suppose to be lost during transmission, but it is practically dropping 1.5 something voltages and these voltages are making differene because ECU is not getting enough voltages, and alternator does have two port signal wire on it which according to some people online are the one that turn on and off the alternator when ECU tells it to be.
And the problem i am facing is low mileage when blower and ac is on, and i am eager to find the problem because mechanics in my country are very dumb and they have practically denied any problem.