General key code

[oldAlbert]

started my van yesterday and the 'CODE' light remained lit up, was worried,
drove 12 miles to work and it remained lit the whole journey.
started the van on the way home and the light went out.
what happened?

 

[Peter Pick-Up]

I guess just an Italian/Brazilian electronic Gremlin....!!

Is the key equiped with a small battery..if so, replace it, if not, live with it