I had the regen issue last December with poor fuel consumption and got that 'hot' almost burning like smell coming from the car. I had never encountered this situation in the what was almost 6 years of owning the car. I followed SRGTD's procedure to the letter and it cleared the issue, but not being able to break 25mpg at the time was concerning me a lot!
Regarding your possible battery issue, I ran it through ChatGPT and got the following possibles.
On a Mk7.5 Golf GTI, the warning “Power consumption too high” generally relates to the car detecting that the 12-volt electrical system is drawing more power than expected, or that battery voltage/charging is becoming insufficient.
Common causes include:
- Weak or ageing 12V battery — probably the first thing I'd investigate, particularly if the car has the original battery or is several years old.
- Battery not being fully charged — lots of short journeys, leaving the car unused, or repeated electrical loads can trigger it.
- Alternator/charging-system issue — the alternator may not be maintaining the correct voltage.
- A module or accessory staying awake — something can continue consuming power after the car is locked, causing excessive battery drain.
- Aftermarket equipment — dashcams, trackers, amplifiers, alarms, etc. can cause excessive consumption if incorrectly wired or not going into sleep mode.
- Battery monitoring/energy-management fault — the GTI has a battery management system that monitors the battery's state of charge and electrical consumption.
- A recently replaced battery that hasn't been correctly registered/coded — depending on the battery specification and diagnostic setup, this can cause energy-management issues.
