Just ran charge / discharge cycle with prolong system. Still have bad module. It says block 3. I have spare hood modules can someone help me identify which ones are #3 I’m guessing it’s the ones I’m pointing at. Just swap those, rebalance and should be good?
Just the answer I was looking for. So opposite end. So modules are paired in two and I would replace those two and rebalance correct?
Just to clarify, you've initially charged to 235V+ and let it cook there for some amount of hours, then once balanced you started the first discharge down to 134V, and the subsequent top charge? Did you also perform any of the successive lower discharge and charge cycles?
Yes. I charged/ discharged three times. Did all the cycles. Upon last charge it was at 238v so I let it sit for some hours and I hooked the discharged up for just a minute to check voltage and it ready 221 idle so I figured I’d t was good to hooks back up and try running the car.
How many miles are currently on the vehicle? No need to replace both modules in the block, just the one, unless both are noticeably lower than the other modules. You can let the pack sit/rest for hours/days, and by using a voltmeter the bad module(s) voltage will measure lower when compared to the rest of the modules. If you do disassemble the pack to replace the module(s), do so after the HV battery has completely cooled off or overnight. Hopefully someone else chimes in, as the voltage difference (.77) seems low enough that block #3 might pick up with additional cycles.
Car has 136k on it. I ran techstream and looks the same the voltage is all over the place in module 3 and 6 looks a little suspect or is that one fine? So I will be swapping these two out. I have a bunch of spare modules I can use so I'll find some that read around the 7.37v range and toss them in and do another rebalance. Here are the screen grabs below of what I got from Techstream. All readings taken in about 5 minutes.
One of the two modules in block 3 has a bad cell for sure. You will find it easier to see the outlier(s) by braking hard and accelerating hard, the bad modules should droop (voltage) under heavy acceleration and spike (spike) under heavy braking. Go for another drive with techstream to see if block 6 is jumping around. Driving hard and parking it hot degrades the HV battery faster. If possible, always park out of the sun or with the windows open/cracked. Run the AC when temps are over 70-80F, this will help keep the HV battery cooler. Increase the HV battery fan speed if you can. Have you cleaned up the HV fan already?
3 cycle discharge is alot. My 07 battery woke right up to one 90 volt discharge and a 30 hour balance. Next one discharge was 4 months later to 134. Every time you discharge it takes a little bit out of the modules this is not magic. 3 discharges create alot of heat and that's very stressful to the pack. Those inside modules get very hot. I assume you had a fan blowing hard on the pack and an IR thermometer monitor along the way. When the pack is in the car the Aux battery fan module forces the battery cooling fan to run full power for cooling during charging & discharging. You have to be very careful when the pack is out of the car you don't cook the pack. It will distort the modules and crack and leak electrolyte. I assume you pulled all the connection black plastics covers off the battery connectors and addressed all the corrosion and checked the ecu for corroded connectors.
