Hi all, recently received a "Hybrid Battery System Failure" Alert on my vehicle which has about 70,000 miles on it. took it to the dealer for the $350 diagnostic and got a P0B51 error code "hybrid battery voltage sensor "E" circuit low". I am not entirely sure what happened, but next thing i know they are telling me i have a new $1000 charge to fix the voltage sensor. Final straw, they now want to replace the entire battery assembly for $4500, because the bus bars are corroded and that the battery warranty will not cover the repairs. Should i keep fighting to get it replaced under warranty (10 years/150,000 mile which toyota recently upgraded from 8yr/100,000miles) - since i believe it is a result of galvanic interaction b/n the copper bus bars and the stainless steel nuts and likely presence of battery fluid BUT they are saying is water damage? should i just tell them to replace existing battery as is and clean the corrosion from the busbars and sensor arrays myself/ at my local shop for time? OR should I bite the bullet and replace the battery? any and all advice welcome i included photos of the corrosion.
no not yet. i am still trying to get them to agree. toyota corporate is BS and cant put me in contact with the corporate warrantee center as only dealerships can do that. dealership wont give me adequate info on why the claim was rejected
My guess is that they can tell it is not original, because there should not be any black marker on any module. Worst case just buy yourself a new bus bar kit from AcenBay.com and use promo code "azusa" to save some money. Then once the new bars are installed, check the battery with the Dr. Prius App. Depending on your available funds you can source OEM modules and replace the bad ones you have. There is also the best option and that is to upgrade your prius with a Lithium HV battery from here. https://projectlithium.com/?ref=mG0GE waiting until after October will give you the latest modules which have better air flow.
My guess is that they can tell it is not original, because there should not be any black marker on any module. You are 100% incorrect with this statement. Anyone who works on these batteries will tell you the factory OEM modules frequently have marks on them like this. And for the OP, that corrosion on the sensing wires/tabs is 100% not from water damage. That is the exact corrosion seen on just about every single OEM battery after a few years of use. It's nothing unexpected. You may want to check the plug/socket on the voltage sensing module. It will often have corrosion buildup on the pins, which will cause codes.
Agree with TMR-JWAP my battery has similar corrosion on bus bars and I know it didnt get wet. Mine isnt as bad but environment can be the cause, moisture in the air, etc. So are bus bars not part of the battery?
If there's a defect with anything contained inside the battery case, and it's within the warranty time/miles requirement, the battery replacement should be taken care of under the car's warranty. If the case was opened by the car owner prior to Toyota diagnosis, broken seals may or may not affect warranty claims. Sometimes those flimsy plastic film tamper seals crack and split on their own after several years.
Question. When I connected my battery charging cable I didn't see any seals or remnants. The car was supposedly only serviced by Toyota. Wouldnt they replace the seals? Or maybe they fell off? Or the seller lied to me? Battery appears to be original. Would like to know the truth.
What battery charging cable are you talking about? Can you explain further? Typically, if the HV battery has seals, they are a piece of green plastic tape about 2-3 inches long and about an inch wide. I don't think all Gen 3 models have it. Definitely Gen 2, tho. I may not be accurate on this, since I'm more of a Gen 2 person, but I'm pretty sure the Circuit E code you got is referring to Block 5 of the HV battery. Whether it be the sensor wire, the voltage sense ecu, or the module itself, it should be covered under warranty. I may be wrong....wouldn't be the first time. You can look at the serial numbers on the top of the modules to get the manufacture date. They should be very close in sequence also. If you find some that are way off, then battery is not original. The date codes should be within a couple months of the car build date.
Could the seals in question be those orange plastic caps that need to be unscrewed with the tip of the safety switch?
