Ask Honest John

Most recently answered batteries questions
Does the 12v socket work when a car is not on or does it work when it's only on? I require a black box in my car and have to keep it plugged in for six months.
Why are electric cars so expensive? Surely nearly all the components are cheaper to produce than conventional petrol/diesel versions.
I have a 2012 BMW 520d. The battery is the original and would not start the car after not being used for two weeks. It's fine when I use the car regularly. Is this a job I can do myself, or does the battery...
Am I likely to have battery problems with a self-charging hybrid if I only do short journeys? Are hybrids the way to go in replacing a car that you intend to keep for a while?
Does charging an iPhone or playing music on it drain a car battery?
I plan to over winter my old Morris Minor in an underground car park that has no source of electric power or light. What do you suggest I do to preserve the battery so it will start after three or four...
What is the best way to maintain PHEV batteries and enable them to keep their charge?
My power steering has failed.The power steering warning light has not come on but the battery warning light is on now constantly. Is the power steering failure due to low battery power?
I have a 2018 Alfa Romeo Giulia with 8000 miles on the clock. The car was running fine until the end of October, but I parked it in a garage overnight for around 11 hours and the next morning the battery...
I have a 1999 Morgan +4. Should I buy a lead acid or a calcium battery? My last battery was a Halfords lead acid and lasted seven years.