help with dr prius battery graphics

Block 8 would be the most likely candidate, based on the graph in your screen shot, but there should be at least one other code (P3018) to go along with your P0A80 that would prove conclusively that one of the modules in Block 8 needs to be refurbished or replaced. Possibly your code reader is not fully hybrid compatible if it is only showing the code you mentioned. In fact, one screen shot alone is not enough to establish that Block 8 is bad, particularly since the difference of .20V between the highest block voltage and the lowest block voltage would not normally trigger a battery code. Before spending any money on the battery, I believe you would be wise to get hold of one of the code readers recommended on this list, if Techstream (the more complete tool) is not a possibility for you.

 

Ok, a 1.71V difference is definitely enough to trigger a code and it's clear that one of the modules in Block 8 needs to be refurbished or replaced (probably replaced because that large of a difference means almost certainly that one of the cells in one of the 2 modules has shorted out and cannot be refurbished). Still your code reader should be showing P3018, so I would suggest replacing it with one of the recommended ones. The C1259 and C1310 don't really tell you anything, just that the braking system ECU has noted a problem reported by your HV battery ECU. It's probably time to start checking prices on new HV batteries from Toyota dealers or from newpriusbatteries.com, or if you want to save money by playing whack-a-mole for a few years, you can read the threads in this forum about replacing individual modules and balancing them to the remaining modules.