Ask Honest John

Most recently answered batteries questions
I am about to purchase a new BMW 1 Series and have been told of a well known problem with all stop start models - that the electrics (battery/alternator) are not able keep the battery charged if other...
I have a quick query about our second car, a 2006 Mercedes-Benz E320 CDI saloon. After a fault-free three years we have now had an alternator fail and, more recently, it is very slow to start, but only...
My Volvo XC60 D5 (205) SE Lux Premium AWD Geartronic was purchased on 24 July 2010. At the beginning of August 2011 I couldn't drive for some eight weeks, and in the third week of August I started and...
I love my FIAT 500 Cabriolet, but it has been back to the dealers many times for the same problem. Every time I leave it a day or two without using it I return to find it will not start. The car is a 2010...
I have a Subaru Forester with a factory-fitted Category 1 alarm/immobiliser. We will be leaving the car for six weeks in a secure garage but I am worried that the alarm will run down the battery. There...
Can you please provide me with appropriate advice and guidance on what precautions are advised and methodology applied when replacing the battery on modern cars with sophisticated electronics, such as...
Have had some problems with my battery draining recently on my 54 plate 2.0 TDCI Mondeo. Following recommendation from the Green Flag man to replace the battery as it is the original battery, I ordered...
Please can you advise me if it will be okay to charge my engine battery on my Ford Transit 2.2 autoroller 200 motorhome using a 12 volt trickle battery charger {spec is input 15vdc 300ma 4.5w charging...
We have a Renault Laguna Initial Estate that we have had from new. It’s now six years old. The last two winters in the Highlands have been very severe. This winter we decided to garage the Laguna before...
My District Council has leased two Nissan Leaf electric cars as a contribution to a cleaner planet. Nissan calls it a zero emission vehicle with a range of 109 miles. The 'zero emission' is questionable,...