Dpf light question

[Hotboxcivic]

Hello. I'm wanting to know when the DPF is meant to turn on. I'm under the impression that when the car is doing a burn the DPF light turns on and turns off when the burn is done. I just tried to force a burn doing 100kph in 3rd for about 20 minutes and the light did not turn on. Cheers.

 

[Old.Tony]

My light never came on except:

1) When I turned on the ignition and the diagnostics were being done
2) When the sensors went silly and caused grief by not being able to sense the regen.

So, basically the DPF light indicated the car's perceived inability to do a regen. While it was doing a regen (and it does a regen approximately every 200 to 300km of driving) the light stayed out.

I think the general idea is that a warning light should only appear if there's a problem with the system, otherwise it's all handled automagically.