The brown could be ignition power, and if I remember right, the Digital DIC needs ignition at two wires, which I used the single brown wire to supply.
The blue wire, depending on which one it is may not be needed, It could be for an "EM Switch", english/metric switch. If you have a HUD, this wire would go to the HUD and toggle between MPG's and KMPL. LOL
I would double and tripple check everyting. Use those wiring diagrams and a multimeter is your friend.
Also, what kind of car, and what year DIC did you get? Some 97's are incompatible, and the GTP and GT DIC's are not interchangable.