Electronic Control Unit, the orange box in the pic. EDIT you'll have the 1.25 ohm resistor in that kit. I'm assuming you have an OE 5 pin ECU and 4 terminal (dual) ballast. You can pull the dual OE ballast & plug in your new ballast to the 2 connectors that were on the lower ohm side of the "dual" ballast. This's let you use your wiring unaltered if desired & if the orange box fails you can easily plug the 5 pin ECU/4 terminal dual ballast back in.
Thank you so much. Yesterday the new set was installed. The guy who did the work said there is no need to replace the resistor and the old one was not replaced. Is it true or should i replace the resistor as well? I feel a slight difference in the ignition and throttle response now.
