HELP my 02 x type 2litre has over the last 18 months developed an annoying intermittent fault. The first journey of the day ,say 10 miles goes fine ,park up for an hour, on return journey the battery light comes on [ sometimes]. Although always gets me home. Had the electrics checked out [with the battery light out ] and was getting 14.42 volts at alternator [normal ] 12 volts at battery [normal ] .But getting diode ripple of 0.49 volts which is high .What does this mean?, any ideas .THANKS Henry