stwatson wrote:It is hooked to a switched ignition source. When you turn the key to start the car, the power is momentarily cut as you turn the key to the cranking position.

HRTuning wrote:As soon as the key gets turned from the off position, it should have constant power to the module.

Find a different power source. It cannot be cut during cranking. Since the ECU is powered full time it produces some feedback through USB to the module keeping it running during this cycle of power even though it doesn't have enough power to run properly (Supply power has been cut). This does not reset the module when power returns, causing it not to go through the powerup connection phase to regain communication.

I see what your saying. I wonder why this has JUST started happening. Before it would work and now its not.

What other 12v sources are normally "tappable"?

Ya, that's odd. Usually it's a problem right away.

The ECU power connection has been used. It keeps power as soon as you key on.

Alright,

I'll look at some wiring diagrams and see if that is actually a 12v source going to the ECU. Then I'll see if I can tap that.

I'll report back.

The ECU definitely requires +12. I've powered them on the bench. Good luck!

Ok...

Here is what I am going to try and do. I am going to run a wire directly from the battery and attach a fuse and switch to it. My question now is what size fuse do I need to make sure I dont over power the tunerview II?

You'll never overpower the TunerView, since it goes through the regulator. However, the regulator could blow. 5 amp, 10 amp. I can't give you a specific recommendation.