The most common reason for this is the earth has been lost - try connecting the head unit to the chassis or some earth wire (best to check with a multimeter). It should fix all your problems.
Hey guys my d22 is doing the same thing dash lights keep turning off and brake lights aren't working
Fuse keeps blowing.
Haven't installed anything but a little led bar that's hooked up to my reverse light with a seperate earth.
Have had the led installed for about a year and hasn't given me any problems so I'm not thinking it is that anyone had this happen to them
Thanks guys
You could try disconnecting the reverse plug and see if the problem persists. In most cases the issue you describe is associated with the trailer plug and/or wireing. Moisture can get into the tail light assembly and give you those drama's too.