Delayed starting on Auto Grandland X

[JimFiFife]

Can anyone help. I have Grandland X Automatic Diesel 1560cc. I have an unusual fault, that my auto electrician or dealer cant seem to fix. When I attempt to start the car by putting my foot on the brake and pressing the start button it will wait for 24 seconds before the glow plug warning light goes out and the car will then turn over and start first turn. Usually first thing in the morning it will start straight away but if switched off and restarted I have the same issue. The glow plugs, the glow plug cables, the glow plug timer relay and the EMU have been replaced. I have also fitted a new stop start AGM battery. Has anyone had similar issues or can offer help please. The auto stop start does not work either.