JVC KD-R200 won't power up for more than 5 seconds

Check your wires they might be touching steel around your car mostly look at your yellow and red wires those are the 1' that give it power and light to your radio also check your radio fuse in the back.

I had the same problem with a JVC KD-AHD69 after clearing trouble codes in my Jetta. I called Crutchfield tech support and was told the symptoms point to constant or ignition switched power sources (both must be on for the stereo to work). Since Jetta has CAN bus and no direct ignition switched power (requires an adapter), possibly the CAN bus module is not working properly. Recommended solution is pull the stereo out and check for power on yellow and red wires when the ignition is on. Check any inline fuses, and (in my case), with everything off, unplug the adapter module for 30 seconds. Then plug it back in and cycle the ignition 5 times about 1 second each. I hope this works...