Hybrid Battery: When doing it yourself goes terribly wrong.

welcome! did you close the orange safety plug according to hoyle? slide it down after latching?

also, it's not as simple as replacing a bad cell with a good one. whose directions did you follow?

try disconnecting the 12v negative for a minute. and press the power button 3 times or some such.

all the best!

 

sorry, i don't know the exact procedure. hopefully, someone with the knowledge will pop in. in the meantime, try browsing the rebuilding threads for tidbits.

 

i don't see anything about reconnecting the orange safety plug properly, when you're done.

and again, just replacing the low cell isn't always sufficient. although it may work in the short run sometimes, more likely than not, it won't work at all unless you balance all the cells properly.

 

Yes the orange HV interlock connector needs to be in place. And it looks like it can be in place, but it isn't.

 

Are you installing the service plug in the fashion described in the pdf file below?

You have to plug it in, pivot the swing arm, and then slide the whole thing into position. Are you doing something like that?

The pdf is for a 2004 {Prius, but the routine is still the same. The plug may be turned differently and in a different location from what is pictured in the pdf file, but the three steps involved are still the same.

Plug in, move handle (swing arm) 90 degrees, then slide the whole thing.

 

From a complete duffer, but anyway:

Even that 7.4 to 7.7 spread seems outside of normal. Also, my limited understanding is that voltage doesn't tell the complete story, it's how similar they perform when a load is applied.

As bisco said, someone should be along shortly who knows this stuff.

 

Okay, assuming you have reinstalled the orange safety disconnect correctly, here's what you
need to do after reconnecting the 12V aux battery.

Put your right foot on the brake pedal
Press the start button TWICE while maintaining pressure on the brake pedal.

This should engage the READY light and enable you to change from Park to Reverse or Drive.

Many make the mistake of pressing the start button only once after replacing the HV battery.

If this isn't it, I have no idea what steps you missed. Hopefully this is all it is.

 

What sort of 'code reader' did you connect? If it isn't one of a very few choices, it'll miss the hybrid and battery codes.

-Chap

 

In your OP, you say all the indicators are lit up. Does this include the MIL (check engine light)? If so, there are DTCs and you're not reading them with your scanner. Getting those DTCs will eliminate all the guess work and maybe a lot of work. You may need to purchase the MiniVCI and the associated Techstream software. It will tell you exactly what is out of spec, and can even do some active testing.

 

Maybe skip the "terminal protecting gel"? Not sure, maybe someone else can comment, but might that be detrimental to conductivity? Toyota installed the bars clean and dry?

 

Sounds good.

After balancing/conditioning my pack with a grid charger, all 28 modules were within .01-.02 volts of each other.

Did you by chance not reconnect the three smaller harness plugs (or incompletely).

 

I don't like the idea of getting warning triangle, then immediately moving to tearing into the battery pack and guessing which modules should be replaced.

You should have a bluetooth OBD or mini vci to pull proper codes to see which modules it says are bad. Then also resetting the codes and driving the car under load to see exactly how those bad cells are performing.

 

Look at the still frame of the video linked in post #7 above. See the black wire harness going into the pack? That plugs into the battery ECU and a couple of other things.