glow plug light coming on while driving

hi,
second post today.
why does my glow plug light come on and stay on while driving?
sometimes its just a faint glow, i never need to use the glow plugs when starting car its always first turn of the key no problems "touch wood"

When you start it up, the glow plug light should come on and extinguish after about 6 seconds?!?

If it then comes on randomly during driving then I expect the relay is faultly and is A putting the telltale light on, or B is actually putting the glows on again which could be caused by a bad connection making the relay think it's been cycled again but that would put the telltale on full brightness or C there is an electrical/earth issue behind the dash or in the loom powering the light

If you don't use your glow plugs you could just pull the harness off the relay in the engine bay and see if the problem disappears, if so then you know its a bad relay, you could also just run with it disconnected, if it was really cold and you needed it plug it in before starting. New ones are about £16.

thanks again for advice but whats an engine bay ?
"joking"
im hopeless and messing about with all this kind off stuff scares me as i always end up breaking everything i touch, i cant help myself.
i shall endevour to take a look over the weekend, ive promised to take my son up Ben Ledi on Sat, if i make it that is.

If not the relay or the wiring - could equally just be moisture behind the dash/corrosion on the dash circuit tracks, causing power to another bulb 'leaking' to the glow plug bulb - would explain the 'faint glow'

Could be a fault with the ignition - they tend to wear inside and let current flow at the wrong time, albeit only slightly. Try spraying wd in the key hole. If it fixes the problem then replace the barrel, if not try something else!

My glow plug light is on all the time.... Even with the key out!!!!
Removing the bulb works just fine for now.
Currently crawling all over the old girl fault finding.