Does the HU overheat? Did u tried touching the body of the HU? Any chance of exposed cables or wiring tape loose and touch somewhere? If your wires are long try to expose the HU to aircond blowing and try to play to see if it restarts or not?If some of the electrical component overheating in the HU better change new HU.The cost of repairing is not worth it.If its expensive HU and you want to try to repair it why dont you send to kenwood service center.

I had one old jvc hifi which i likes alot.One day due to lighting spoilt.Tried many shops cant get spare part.Went to the factory at shah alam.It was repaired cheaply and fully serviced.They have alot of spare parts even for the older models.

http://www.kenwoodworld.com/en-MY/customer-services/
http://my.kenwood.com/Support/Contact/

Change the player lor since its very much cheaper than changing the car..