Hi.

Driving round the motorway roundabout before a 250-odd mile journey
last weekend and this light illuminated on my dash. Red cog with an
exclamation mark in the middle of it.

Oh dear.

I didn't stop - because I was unsure as to whether the car would go
again if I did. Drove it straight to a local Ford garage. There was no
loss of power. No odd noises. Nothing unusual - aside from the light.

After stopping and switching the engine off the car started again
first time - no warning light.

The service dept. was on half day, so I asked a salesman about it.

We chatted, he noted that sometimes on a diesel these lights come on
if a sensor detects something a bit funny. But if they go off again
and the car drives normally, it's nothing to worry about.

So I set off on my merry way. Did the 250 miles on the Saturday. 380
on Monday. And then 250 miles back on Wednesday. Car running (fingers
crossed) as good as ever.

So to the question.. What causes this?

Thanks.