Outer Limits 4x4 Board

Only started yesterday before that it ran really well, when i went to start my NH swb paj the plugs wouldnt pre glow (wont click), checked all the fuses and they seem good. It will eventually start and run.
Im a little lost this is my first diesel so still working it out. My thoughts are that it is the relays but i dont know which ones it will be.

Anyone have a wiring diagram for the glow circuit?
Or any other ideas?

Hey mate I don't no were there are or which ones they are but when it
happened to my hilux and it still is i can't find the problem and can't find it all I did
was take the wire off the glow rail and put one that reachs the battry
and hold it on for 10secs that way when the car is cold it starts first go
I m going to fix it but all in due time