Hello I've had a light come up on dash of a Ford fiesta ztec s diesel 58 plate which is a amber cog shape with a exclamation mark inside of it, I went into the hidden diagnostic menu but now it won't seem to go back to the normal menu which shows you mpg, mileage till I need to put more diesel in, average speed anyone now how to get it back to normal?

Don't know about how to get correct menu back up but that dash light came up out of nowhere in my daughters 1.6tdci 07. It went to limp mode and error in diagnostics came up as glow plug relay. Rather than order a new relay my mechanic thought it best to check the glow plugs on his machine first while there were in situ as faulty glowplugs gives the same error description. He was right. All the glow plugs had failed for some reason so he replaced them with NGK ones.Never needed the relay after all even though diagnostics showed this was the case.

I think on the fiesta you press the end of the indicator stalk to toggle through the menu to get back to mpg. The manual will tell you the method.