Tranit 130 T280M FWD - intermittent warning lights

[kevinj]

Tranit 130 T280M FWD - Our transit has for some weeks now has exhibited a ABS & ESP Warning Light for a short time then
it goes off. Yesterday the lights went on when started, after the van had sat idle for a few hours. Other times has come on and off whilst driving.
Cannot find any actual fault - any remedy please?
15th March Now the weather is not wet the problwm has stopped - must be moisture!