My Renault Megane 1.5 dci has an alternator problem and the battery light illuminates on the dashboard. The trouble is I don’t know the radio code. Would there be any problems if I changed the alternator without disconnecting the battery? Gino
There would be no problems caused to the alternator or charging system by replacing the unit without disconnecting the battery, but the danger of shorting out the main feed wire to earth while carrying out the job would be very high. Shorting out the feed cable to earth would cause serious problems and could be very dangerous.
The alternative would be to use a fused battery saver device. Although you would still lose the radio code if you were to accidently touch the cable to earth, at least you would not be at risk of more serious danger.
You should be able to get the radio code from your nearest Renault main dealer. They normally require the V5 as proof of ownership and some will charge for the service.
There are also companies online, such as radio-code.co.uk, who will supply the radio code for a small fee.