So I helped a buddy install his gauge yesterday, which was a HUGE pita! 30 minutes for my Defi, 5hrs for Pro Sport. Anywho, after extending all the wires we got it to turn on. However it flashed red, white and blue. We played with the wires and finally ended back in the original config but the gauge would only flash red and white It does NOT turn off with the key either. Here is a video:

I read somewhere that it could be not communicating with the sensor unit so maybe he didn't get a good connection when he extended those wires but any other ideas?

 

I'm running the prosports without a issue. I used the headlight fuse for the color swaping, and powered it from the cig lighter.

 

Follow the wiring instructions that came with the gauge. If its staying on with the key off its for sure your wiring. You should have a constant 12v a ground and accessory 12v that tells the gauge when to turn off and on. You can tie the 2 12v wires together and tie them into the cig lighter 12v connection so whenever your cig lighter has power so will your gauges. In other words it will turn on whenever your key is turned over. That would be the easiest way.