I have had several diesel cars lately and now this 535d. All other cars when I put the key to ignition and turn on ignition there is a symbol, like a spiral, showing that the glow plugs is heating. WHen it goes out the car is ok to start. I have seen this spiral in te little display between the speedo and rev-counter on my 535 only 2 or 3 times, even if there has been cold outside over night and starting.


So quetion is, do the glowplugs start heating whenever / as soon as the car goes out o sleep-mode? (As soon as I unlock it)?
And if so why do I get this symbol this 2-3 times when I saw it?

 

I've seen the exact same behaviour and suspect it only happens on the coldest of morning (-3 or 4 C) when the glow plugs can't quite finish their work before you go to start the car. I would guess they start up as soon as the car is unlocked (as does the fuel pump I think).

 

most common rail diesel engines (although they have them) dont need the glow plugs to start the car...the high compression and high pressure "mist" from modern common rails are enough to create the required compression / mixture.
if temp drops low enough they will come into force, but the BMW engines today are not like diesel's of old where you had to wait a few seconds before cranking the car.

not a compleate explanation, but thats roughly whats happening.

 

+1 on that