For many years now i've been keeping the car ''live'' with jump leads jump pack or if none available a bit of jerry wiring a lead from another battery to the terminals whilst the battery is changed, but you have to be careful not to short the thing out as the battery leads tend to return to position and the live might touch earth whilst your back is turned..a bad thing.

This practice is since i was having a chat with an AA breakdown chap retrieving a new Rover 800 Sterling from a rental office compound, the battery of which had gone flat and the car in his words lost its memory.

They don't worry about such things at car compounds where thousands of cars are stored, simply connect jump leads and fire up, the odd one (tiny number) that goes awry they simply drag out and send to the nearest main dealer.

Probably a bif of faff for most people, but sods law dictates that the one time i don't do this the initial spark from a new battery will kill something very expensive hence my faffing.

Some cars need different things resetting if power is lost not just the radio/clock (altimeter/barometer/compass/outside temp recorder on my Landcruiser), some newer cars apparently need 'telling' that a new battery has been installed however you change it or it won't charge right, i believe this is the case with new BMW's, some older BMW's needed the steering position resetting for ABS to work, and variations on the above.

There thats helpful innit...:-)

Edited by gordonbennet on 25/04/2016 at 10:51

Thank you to the people that have replied. I have actually just spoken to a Honda technician who has re affirmed what 'bolt' has just said. Negative off, positive off, change battery, positive on, negative on. Job done.