Kenwood radio installed ATT keeps coming on and off as i brake

SOURCE: Volume turned up, kenwood shuts off briefly...

I had this same exact problem when my last older Kenwood Marine stereo cooked itself while I had it up loud for a few weekends on the lake. (smelled like it had burned inside). I went out and bought a new Kenwood KMR-550u stereo deck. (I do not have an additional amp). I hooked it up to the exact connections where my older Kenwood stereo unit had been hooked up, as I never had a problem with this for the past three years until it failed after smelling of burning elelectrical. I had chalked the problem up to heavy rain we had one day. Every time I turned up the volume, sometimes up to 27 out of 35 possible, or 29, or 32, the stereo would suddenly shut off as if I had turned it off. After a few seconds the stereo would come back on, but unless I was quick enough to turn down the volume it would do it again right away. Of course on a boat, we were beached in a cove and the engine was not running when I encountered this. I searched the internet finding hundreds of similar complaints and several dozen theories of all types, but only a couple that pointed me towards the power (voltage) idea as the problem. I put a volt meter on the positive & negative wires powering the stereo. I watched as I gradually turned up the volume, the voltage on the power wire gradually decreased from 12.5 volts, down into the 11 range, and as it hit 10.9 or 10.8 volts it shut off typically around a volume of 32. The red power wire in my boat that never seemed to have an issue with my old stereo until it fried was determined to actually be inadequate for the power flow for the new Kenwood, and probably was the culprit of my failed older unit. I offer this sound advice: Run a new pair of positive & negative wires directly from the battery (with an appropriate fuse of course (the deck has a 10 amp fuse in it's back so I would use that at the battery) to the stereo. Check the voltage as you turn the volume up into the high 20's and low 30's to ensure you are still getting voltage in the mid to high 11-12 volt range. The stereo is designed to require a minimum of 10.8 volts to operate, and when it drops below that it protects itself and shuts down.

SOURCE: Kenwood stereo Won't turn on

look and see if there is a reset... usually a tiny hole you can push a pen point into...(lightly)

SOURCE: Volume turned up, kenwood shuts off briefly...

does it keep cutting in and out?
if so i think you have your polarities crossed
make sure you have negative to negative positive to positive