My new 2005 Prius hybrid battery trouble shooting

Thanks everyone. That makes sense. So im going to get a new pack.

After my grid charge , driving that first day i got 55 mpg. I womder why ? Lol

Anyway the beautiful All .027 ohm IR lasted about half a day. Now 10 amd 14 are .030 amd .029 when i start. I threw the replace battery code the next day on a long flat stretch when i was really working the battery, breaking my ev only record of .5 miles. Lol. So that makes sense with what Jim explains.

now i have changed my driving habits -- i give it gas amd keep the gas engine going or glide so as not to put too much load on battery. it has been 2 days and no code and 47 mpg avg.

So now my hypothesis is that Toyota's firmware in the battery control module is too finicky and could use a tune to not throw codes as much. Anyone else suspect that?

For this to be possible , it would have to be true that having one weak module wont detrimentally deteriorate the rest of the pack quicly. Battery gurus -- what is the practical downside of driving with a weak module ? The other modules dont see as much charge and discharge. That could lessen their life maybe ? Or extend it maybe? At any rate , they could be periodocally grid charged for maintenance.

This week i am driving it like a regular car not trying to hypermile it and making sure i dont stress the battery. Im going to see if i can break my 3 day record of no codes. I cant argue with 47mpg.
Also i put it back on the grid charger tonight. Maybe some periodic grid charging can bring the weak modules back a little bit. I would like to figure out how to discharge it driving.

Im going to look into programming the battery control module, eventually. My guess is i wont get very far.
Even just putting in a filter in the can bus line or whatever to catch the battery module codes and throw them out if they are sporadic might be doable. Im no car hacker but i am a software developer. Id love to get with the tuners and see what can be done.

Do scan gauges clear all codes with one button click ? Ive never used one. A button on dashboard to clear codes would maybe help people go a long way with weak modules. Ive gone what two or three weeks so far.

 

Thanks! I let it go 12 hrs. Yes it runs the fan. Maxx says when the voltage stays steady let it charge 4 more hrs. Thats what i did last time. I could let it go all day tomorrow.

So if i put it in ev mode amd drive it til it died would that count as a deep discharge ?

Regarding clearing codes not doing much -- i disagree. For me its been three more weeks of driving without having to take car to mechanic and a several thousand dollar bill. Maybe it will go a year like this ? That would really mean a lot.

 

I may have found a way to discharge hybrid battery fully or to whatever stste of charge i want. Put car in neutral amd run ac and the ice won't charge the battery. Im going to give it a go. I saw this on greencarforums :

It is normal for the battery state to drop rapidly when sitting stopped with the AC running. I see that almost every day here in Florida. Running the AC takes more energy than you might think.

When I am stopped in traffic, I normally leave it in "D", with my foot on the brake. I sometimes put it in "P" while waiting for a draw bridge. In both of those states, the engine starts when the car decides that the battery needs to be recharged.

The care will NOT run the engine to recharge the battery while the shifter is in "N". I think I read that here, somewhere. But today the best explanation I can find is on a lexus forum: http://us.lexusownersclub.com/forums...howtopic=65264 :

"From the shop manual - "When in neutral, MG1 and MG2 are shut down. This is because MG1 and MG2 must be stopped electrically as a means of shutting down the motive force, since MG2 is mechanically joined to the front wheels. On the 4WD model, MGR is shut down as well."

"So what this basically means is MG1 is shut down in neutral because MG2 is connected to the front wheels and in neutral you don't want any power going to MG2 from MG1 since you don't want the wheels to be powered. However, MG1 also charges the battery as well as powering MG2, so it can't charge the battery when in neutral because it's shut down so it doesn't power MG2."

 

Thanks all. Yeah the plan is to get a good battery from jim amd then make this one better, experiment with it.

In theory it is possible to bring the cells back to life and relearn how to work together by some deep dishcharge cycles?

 

Thanks. dolj. I've been reading on discharging. My understanding is discharge at like down to 6 V.

While reading this YY4U story here Traction battery rebuild question | PriusChat, someone mentioned something about the wires on each pair of modules that go to the ecu to tell it the voltage of each module. I don't know why i didn't think of this earlier. No need to hack the ecu. If this voltage is what is used mainly to throw the replace battery pack codes -- too big of a difference in voltage between modules, just take the voltage reading wires off the bad module and put them on a good module ... presto. I haven't seen those wires yet to see how easy that is to do.

The idea is that by lying to the ecu, I could buy some time -- wait for some more modules to go out before doing all the work to replace just one or two modules.

 

Dang. I was wondering how they were going to read each individual voltage with them wired in series. Makes sense. Thanks.

 

Alright. I threw in the towel and got a newer module feom tmr-jwap. I realized i didnt really wamt to take apart my pack, check all them, replace modules, put pack back together , then charge amd discharge for 4 days to balance it. So i got a newer pack from trw-jwap amd he got mine to do all this hard work.

I mean that would be like a full day of hard work at least for someone who has never done it. Then 6 months later , more modules go bad. Maybe when my new pack gives me trouble in 5 years ill feel like taking it apart and replacing modules.

No im happy drivig wothout having to clear codes everyday. I can pulse and glide , and got 48.9 mpg on my last tank without even trying. Thats about 5 mog better than with my old pack.

Anyone need a grid charger ? Pm me