Prius II HIV battery module change

Actually split the pair of suspect modules and mate them to other pairs. Also, look very closely at the terminal. My failed modules often show evidence of the black "O" ring melting or smearing around the terminal. You might be able to detect electrolyte loss with a pool pH test solution.

There is a plastic 'mesh' that separates the cathode and anode. What typically happens is a loss of electrolyte concentrates the current in a smaller and smaller area. Eventually the current gets high enough to heat and melt the plastic mesh separator.

Bob Wilson

 

I have a spare ECU from my 2004 Prius that you could try.

JeffD