Citroen berlingo electric fault

[Bottsey]

Hi, I have a Citroen berlingo multispace year 2000 and when I start the car nothing usually on the dash works speedo taco any gauges but after a short time they start to work on and off then they just work all the time. I guess it could well be damp unless someone thinks differently if it is the damp where would you recommend I spray the wd40 to help clear this problem. Thanks.