I took mine in for the Shaker500. The car had to sit there for a few days because it required my head unit be sent in and another returned as a one for one swap. BS if you ask me. Anyway I drove it home and the next morning driving into work in the dark notice the head unit doesn't light up (I didn't even know the speed volume didn't work). Took it in and the tech who did the work asked another tech about the problem. He then was told it had to be programmed into the PCM. Tech told me there were a bunch of them out there he swapped that didn't work right because he never knew he had to program it.

 

+1

 

..only ford

 

I drove a Pontiac G6 and the functions that Mustangs have with the IUP, (MPG, Miles to Empty , timer, etc) are displayed on the factory stereo display instead of in instrument panel. This tells me that some of GM's factory stereos are tied even more into the ECU than Ford's are.

 

i didnt have this problem at all. i have the KB tune in the car and when they repalced my shaker a few months ago there was no issue. in and out in 40 minutes with the KB tune still in the car. I have the shaker 500 by the way.

 

This leads me to beleive its the locked tunes that would cause the problems...

 

who knows, i think this is a case by case deal. in the end the dealer was able to figure out how to get it all working anyway. My message to anyone is not to worry about it.

my shaker 500 has been fine since the day i bought my car.