replacing a bad cell do i need to balance all cells ?

Block 10 is weak and, I believe block 6 may be starting to have problems too. Or, the pack may just need reconditioning (careful deep discharging & recharging). It is difficult to tell.
@TMR-JWAP here has done a lot of battery testing & evaluation in his hobby. He could better inform you.

 

I am in same situation. The car is not going to HV mode. The engine runs continuously. Were you able to fix it?

 

What situation is the same? What car are you talking about? "The car not going to HV mode" and "The engine runs continuously" is not really useful information.

Generally, it is not a good idea to tag onto someone else's thread (which is called hijacking) and if you want to diagnose your car you should start your own thread in an appropriate forum and begin by stating what codes your car has.

 

He did create a thread for his problem. Take a look at this link: https://priuschat.com/index.php?threads/245008/

Posted via the PriusChat mobile app.

 

First, I didn't hijack his thread. Also I only asked if he was able to fix it.

Generally, it’s good idea to read everything what someone has posted before becoming keyboard warrior.

 

So no need to cross-post, then.