CM 871 won’t regen

[theironoracle]

New problem!!! Truck won’t regen with the button or with insite. Gets right up to 500+ degrees DOC. As soon as the injector opens the coolant low light comes on and aborts regen. Performed the same 4 times. Found broken wire on level sensor plug. Does low coolant level actually keep the regen from working or is this a sign of something else? Why does the light only come on when the injector gets ready to fire?....TIO