12V Battery Cable help ASAP

are they not balanced? so do I need to attach the computer only?

 

They are new. No balancing bs needed.

 

Is there a diy for attaching the ECU?

 

DiY? Remove 3 nuts circled in green, to move the ECU portion to new pack. Also check orange socket and ecu board for corrosion.

New OEM hybrid battery - 6 months old | Page 2 | PriusChat

The battery fires at ECU sense connector thread | PriusChat

 

Thank you! this is very helpful as there no videos available for ECU swap, I have decided to buy a brand new battery from the Toyota dealership for $1635 plus tax and install it myself. Apart from the things you mentioned above, do I need to take any other precautions?

BTW I'm from Calgary and have recently moved to Houston.

 

Take pictures of old hybrid battery, both sides. Only puzzle might be the 3 orange cable routing if you forget to take a pic.

 

Yeah I was wondering about that, thanks for the heads up!

 

If there is corrosion on the Ecu connector then what? Does it need to be replaced?

 

If cleaning the corrosion (or replacing the harness) fails to relieve the stored OBD2 code(s), then a replacement would be the next option.

 

How can I clean it up?

 

Try cleaning the ECU pins with a widdled down piece of emory board or very fine sand paper, then gently rinse with alcohol/vodka and dry.

If the corrosion is that bad, then be sure to take a peak inside as mentioned above.

More images :

The battery fires at ECU sense connector thread | PriusChat

The battery fires at ECU sense connector thread | PriusChat

 

I absolutely wanna make sure it’s the HV battery before I buy a new one. I replaced couple of cells last time which were 6.2volt with 7.2volt, is that low as well? All other cells were above 8volts. Red triangle showed up again after 5 miles.

 

When replacing cells, you need to charge the "new" cells to the same voltage as the other cells in your battery or the ECU will flag an unbalanced battery.

JeffD

 

... and the "new" modules need to be of the same general capacity as the existing old modules.

 

How do I charge them?

 

You mean above 8volts in my case?

 

You use a hobby battery charger - about $40



JeffD

 

Thanks, after I charge them do I need to discharge them? Do I have to do this cycle few times? Also how would I discharge them? Is through the same equipment?

 

Gen II Prius Individual Battery Module Replacement | PriusChat

Module Capacities..I wouldn't believe it if it weren't sitting on my work bench.... | PriusChat


DIY Refurbish / Repair Hybrid Battery 2nd Gen Toyota Prius

Prius Hybrid Battery - The 101 and DIY Cell Module Replacement

 

And at the end of the day a bunch of diy leaves you with an unreliable battery and no warranty.