So I'm having an issue with my battery not holding charge which seems to be getting progressively worse, to the point where it is now discharging below the required voltage to turn the engine over if left for a day or 2.
The battery is 3 years old and is of high quality (supercharge gold) and when placed on a 7 stage charger does not indicate any faults so I'm starting to think I may have a faulty diode in my alternator.
Using my obd reader and torque app I can see that the alternator is charging ok at between 13.8 and 14V while the car is running.
Anyone had a similar issue or know how I might be able to diagnose the culprit?