codes+lights+drama; my head is spinning

Patch all the wires then erase codes

 

The C codes you've got mean only that the traction control ECU knows you've got the B codes. So you don't have to sweat those.

 

Hi C1TRU5,
I'm no expert, but this is what I would do:
1. Disconnect the 12 V battery by disconnecting the negative terminal from the battery. Observe normal cautions about not shorting your tools ;-)
2. Check the battery voltage with a voltmeter. If it's below 12.4V put a charger on it for 12-24 hours.
3. Reconnect the 12 V battery. This will possibly clear some or all of the codes.
4. Power up the car in the normal way. You might have to push the power button once, wait for a while - 30 seconds or so - and then push it again.
5. If the car starts normally, leave it running for a while (maybe up to an hour) with the Ready light on. This will charge the HV battery. I recall something about having to lock the doors with the metal key if you have a smart key. Obviously you don't want to lock yourself out of the car.

Many people on here are way more knowledgeable and experienced than me and they'll hopefully clarify some of the above. I've had a lot of experience with Priuses with problems like you describe and there is a lot you can fix, and a lot you can get away with and still drive (not forever but for a while)

The jump start probably/possibly was not done correctly and may have caused some of the codes.

Good luck and please keep me posted.

 

you might need a new 12v, how many miles on her? i wouldn't blame your parents, tough for a prius to sit for extended periods of time

 

Lots of possibilities there. Maybe reversed polarity jump start. Or mice...

 

Hi C1TRU5, My, admittedly amateurish, experience has been that disconnecting the 12 V bat and having it disconnected for more than 30-90 seconds clears at least some of the warnings and let's my Prius get a "clean(er)" start. Then running or driving the car gets the HV bat charged. Repeating the process, with charging the 12 V bat as necessary sometimes gives me a completely clean start. I've also found that mice or rats or squirrels chewing on various wires only very rarely creates a real, disabling issue. It's definitely not an enhancement, but it's not the first thing I would fix either. The 12 V battery (and I'm going to get some flak for this for sure) I've found also is not too critical - it has to have good voltage and power, but it only boots up the various computers, so as a temporary measure you can use any good 12 V bat. Some Prius heretics use cheap 12 V lawnmower bats!

Again, many here are far more expert than I, and I use their valuable advice all the time.

Good luck. I think you'll find your car is not ruined after all.

Does your car currently start?

 

I'll try not to jump to far ahead with what to do next if - replacing the 12 volt or getting the one in the car to hold above 12 volts - doesn't fix the issue of the Traction Battery not charging at all presently.

 

Hi C1TRU5, I made the 12 V lawnmower battery comment mostly to point out that the Prius specific 12V bat is nothing magic. A good source of "around 12 VDC" is required to get various computers up and running. What your parents likely did not know, and I didn't either for a while, is that doing a "jump start" on a Prius only requires providing a stable 12 VDC input to boot up the computers - there is no need to have another vehicle revving up, or some giant Costco battery jump start device, to provide this.

As you likely know there is some parasitic load on the 12 V bat when you leave the car sitting. This can run down the 12 V bat enough to preclude an assisted start. I think maybe the HV bat "recharges" the 12 V bat in this circumstance, and I'd welcome hearing from the smart people on here if this is so.

Glad to hear your car does start and run. I have the same issue with one of my Priuses - the ICE engine never shuts off. I'm getting around to trouble shooting that with much help from people here.

As you also likely know, the engine is started by the HV bat. I don't know enough about the systems to know whether various protective devices preclude the HV bat from getting too far discharged to prevent it being able to do it's starting function (I have that issue I think with another of my cars - the HV bat might be too low to do the start). And similarly what protective systems prevent the ICE charging the HV bat in the event of a problem, including weak or out of range modules?

What I have found, in limping around with these old cars, is that disconnecting the 12 V bat every single time I shut off the car, even just to go to the beach, allows me to get it started again once I need to drive. Obviously fixing the various problems is far better and I'll get to that. My Priuses are old so disconnecting the 12 V bat is easy - I just unplug the "big white plug" to the positive bat terminal. Prior to knowing about this plug I would disconnect the negative terminal with a suitable size wrench.

All of the above is to say that yes, it's pretty confusing and overwhelming. And from what you say your problem will require more than getting a new 12 V battery, although that seems to be the common first recommendation. I would do that (your car is new enough to be worth fixing), and make sure you keep the new 12 V bat trickle charged while you get the other problems sorted out (I suggest trickle charging with the 12 V bat disconnected from the car, but I'm not 100% certain this is required.)

Good luck. Please feel free to continue the discussion. If we attract the attention of the smartest folks on here, we're home free ;-)

 

If you can narrow it down to the HV bat then there is a lot you can do. Or like me you can just guess that it's the HV bat. There are various chargers and testers for the HV bat. You'll be getting into this deeper than you may want, but it's not all that tough. DrPrius has a good app for testing the capacity of the HV bat. He has a bunch of videos on youTube. Hybrid Automotive makes a device called Prolong. It's basically a charger and discharger which may let you "recondition" your HV bat. I'm cheap so I didn't yet get that. I got a Mean Well LED power supply which will do the charging, and a constant current/constant voltage power supply to let me recharge individual modules.

The guy from DrPrius did a couple of youTube videos on the Prolong which I just watched. It doesn't "make you a new HV battery" but it should give your HV bat enough life for you to feel you have a working car again. After that if all else is good you can decide if you want to replace or rebuild your HV bat. A lot of options exist to do that, most of which are less expensive than you might fear. (My cars are older and in terrible wet environments so I'll likely just keep them limping along until they rust away rather than installing new HV bats.)

My suggestion is to get the Prolong unit, and the DrPrius app. I think you can pretty easily resell the Prolong if you decide you don't want it (maybe even to me)

Good move getting a new 12V bat. That takes that out of the equation!

At least with your ICE engine running you can drive when you need to. You might consider disconnecting the 12 V bat whenever you park, although that is a nuisance. Supposedly the car will not let the HV bat deplete so far (during use of the electric part of the hybrid drive) that it can't start the car. But each start does "use up" some HV capacity, so it's a good idea to monitor whether your HV bat shows as getting charged when you drive. And/or you can just park the car with the Ready light on and leave it running until the ICE either stops or the HV bat shows as well charged. If the ICE does stop it indicates the car thinks your HV bat is well charged. (My ICE doesn't stop, but the HV battery shows pretty good charge, and does start the car)

If you do decide to dump your car instead of going thru all this please let me know. I'm in SoCal (and Kauai) and while PDX is far I'd risk driving it home to San Diego ;-)

The smart guys on here are probably reading our posts and laughing. They'll chip in when they find it funny enough ;-)

 

Assuming the "same exact error codes" are the ones in the original post, it has been narrowed down to the HV battery the whole time, no guessing involved, just opening the repair manual to see what the codes mean. Sometimes I wish we wouldn't put owners through as many posts as we do looking in every direction other than where the evidence points.

These codes do not necessarily mean the (expensive) HV battery has to be replaced. In fact, they probably do not.

Inside the battery, there are 28 identical modules. They are divided into 14 blocks of two modules each, and for each of the 14 blocks there is a voltage sensing wire. The modules are nominally 7.2 volts each, so each block should measure around 14ish (or a bit higher when more charged).

The three codes in post #1 mean that three of those voltage sense wires are giving readings less than 2.5 volts. That is almost certainly not an indication those battery modules are bad. Even a pair of bad 7.2 volt modules ain't going to give you a reading below 2.5 volts. A reading that low is almost surely telling you that three of those skinny voltage sense wires have gotten corroded or broken. The wire harness that contains those is around fifty bucks.

It's also possible that the sensor electronics where those plug in could need replacing too; there's a common thing that happens at the orange connector where that wire harness plugs in. It should be carefully inspected. If it needs replacing, it's not super expensive, especially as a used part.

The biggest caution about doing the work is the voltages involved. Death is a readily available option. It might be worth paying a shop to deal with it just for that reason, though there are also plenty of threads around here (and videos available) with details on tackling the job.

 

Crazy ...I was about to call your mechanic bad names for saying the harness wasn't available separately. It was in Gen 1 and Gen 2, and reasonably priced. But sure enough, in this Gen 3 diagram, it's shown with "N03 This part is not supplied as an individual part, because it is difficult to keep the function / quality of part assembled".

As a Gen 3 owner myself, I am not happy to be learning that.

 

Umm...I have a bunch of these harnesses.......like a TOTE of them....