OK, so my son has a 2011 CRZ with 85K on it. The IMA warning light keeps coming on, likely after it blows the fuse 53...multiple times. Sometimes I can drive the CRZ 50 miles before it blows the fuse...sometimes not even a mile. I went through all of Honda's diagnostic tests in the manual. The blow fan gets 12 volts and feeds back 5v. According to Honda diagnostics, the IMA battery fan is good. Just to verify, I bought a used IMA fan and it does the same thing. Sometimes I can hear the fan, but shortly after, it stops and IMA warning lights and charging lights come on. I have checked the 2 IMA relays and they are also working and good. The 12v starter battery is only 1-1/2 years old. It is a Honda OEM and it charges to 13+ volts fine and I had it load tested just to make sure it wasn't having that kind of issue and it is fine. Obviously, when the IMA lights come on, it no longer is being charged by the inverter so it starts to lose its charge. I am at a loss of what to do other than to change out the MCM blower fan control unit. Anyone have any other ideas?? If I do replace with a new or used MCM ($100 used, $200 new) does anyone know if it will need to be reprogrammed or have a software update by a Honda dealership, or should it work fine as-is?