News on battery rubber vent smell

1. Please provide a full list of the problems that your Prius currently has, besides an odor issue. Some owners have reported odor caused by the air conditioning system needing cleaning, so you may want to investigate that and make sure that is not the cause of your car's odor issue.
2. Remove the little triangle-shaped hatch floor trim to expose the 12V battery.
3. Make the Prius READY, and measure the voltage across the 12V battery. The voltage should be ~13.8V.
4. Now make the Prius IG-OFF. Given the smell being as strong as you've described, if you get within a couple feet of the source, your nose should be able to identify the problem. So remove the folding hatch floor and the black plastic tray over the spare tire, and smell around the 12V battery. If you determine that is the problem, then remove the battery and satisfy yourself that is the source. While the battery is removed, make sure there is nothing nasty in the fender well.
5. If your nose tells you the 12V battery is OK, then remove the orange traction battery interlock switch for safety. This is done by pulling the lever out so the switch can be removed from the battery case.
6. Then remove the remaining floor trim over the traction battery case, remove the traction battery case cover and smell around the two black vent hoses to see if they are the problem. Even though the safety interlock is removed, you can still get zapped if you contact the battery modules, so keep away from their terminals.
7. While the traction battery case is open, take a good look at the orange busbars that connect the modules, looking for corrosion. If this is present, the modules involved are leaking electrolyte and you will eventually have a ground fault DTC logged by the traction battery ECU.
8. After you are done inspecting the traction battery, replace the cover and the floor trim. Install the orange interlock switch. Pivot the lever 90 degrees, then slide the lever down to lock in place.

 

Thanks for providing the list. I just wanted to ensure your car did not have other problems which are related to the odor problem.

1. The steering problem sounds like a safety issue, the local dealer or a competent independent needs to evaluate the steering system and explain to you what is going on. I hope you can demonstrate the free-play and jumped tooth issue upon demand. The dealer service writer should be shown your observations.

1.1 Regarding the lower control arm bushings that no longer creak after being sprayed with lubricant - excellent detective work, it sounds like you have determined exactly what is the problem. If the noise returns you will know the control arms need to be replaced (I don't think the bushings can be separately replaced.)

3. When measuring voltage across the 12V battery, first measure the voltage while the car is IG-OFF, first thing in the morning before the car has been driven, to see what the open-circuit voltage is. Then make the Prius READY, and measure the voltage again which will show what the DC/DC converter voltage is.

 

how many miles on her?

 

I haven't needed to remove the vent tubes so I do not know what is involved. It would be a good idea to wear some sort of glove protection when working on the battery to protect your hands from possible electrolyte leakage, not to mention the high voltage present.

3. The 12V battery measurements are good. They indicate the battery is in reasonable condition and that the DC/DC converter is not overcharging the battery.

Did you consider removing the 12V battery to see if the smell follows the battery or not? That would address the suggestion from the link you referred to in post #30.

 

There, I fixed it for you.

Do you think that no one else here owns another car? Or that no one ever travels in other people's cars or has non Prius accustomed passengers sometimes travelling with them?

I often have passengers who are totally unaccustomed to the Prius, some of them world class whiners and complainers, and yet so far not one compliant about a stinky Prius. Now given the many people who actually have the problem say that the smell is so bad that it permeates their clothing for days, I'm absolute certain that (even if I was somehow immune to the smell) I would have received some complaints by now, but yet there have been none.

Look, no one comes onto these forums and says "My Prius has a flat tire. Therefore I believe that all Prius have flat tires all the time, but people just don't notice it". For some reason however, just out every time the topic of "stinky" Prius come up there is always at least one person wanting to claim that it is a universal problem.

Given that the problem is reported here from time to time makes me believe that it certainly is a real issue, however I am in no way convinced that it is anywhere even close to being the "universal" problem that some people suggest.

 

your ig off should be 13+ on a new battery. it may be something as simple as trickle charge to bring it up to speed, the car won't do that for you. my 3 year old battery is 12.7v.

 

Are these fasteners between hatch floor and top of battery?

In my experience, albeit with 3rd gen, while they were pretty tough to pop free, none broke. A few slipped out of their (open slot) moorings on the floor underside. Because there are also hooks and a bolt, I elected to leave all the plastic fasteners OFF at reassembly. It makes subsequent removal much easier.

Again, this is with 3rd gen, but I don't think you should dwell too much on the fastener issue.

I keep thinking you could cobble something, to replace the (allegedly stinky) vent tube: appropriate diameter vinyl tube, with holes drilled in it at the cell vent locations, a stopper at one end, connected to the original vent conduit.

Or use smaller diameter tubing, branching out from a trunk line with T-connectors.

 

Hi Battery Driven. I've had a 12V battery very similar to that one of yours installed in my Prius for over two years now. I know it's not an ideal OEM replacement, but mine has given me absolutely no problems so far.

With the vent tube and the elbow not fitting properly, on mine I just removed the elbow joint and stuffed the rubber tube directly into the vent hole on the battery. It was a fairly snug fit and I think it is sealing ok. I did also wrap a bit of plumbers (teflon) tape around it to make sure it was tight, and it seems to be doing the job. Also, on my replacement battery there was a vent hole in both ends of the battery, so if yours is the same then make sure you plug up the unused one.

My post here has some more details if you want to take a look: Finally replaced my 8.5 year old 12V battery! Non AGM??? | PriusChat

 

I monitor the middle temp sensor on mine. There's 3 sensors along length of pack, and middle one supposedly hottest. Anyway, highest I've seen (with ScanGauge) is maybe 45C. I'd guestimate highest would be 50~55C.

 

Thinking about the price of those vent tubes, it seems to me:

If there's a part that's easily replicable, a lot of potential customers just circumvent the purchase, make something up from commonly available (and much cheaper) materials. And that just drives the part price up more, 'cause no one's buying.

As far as temperature, I think you'd be ok with black vacuum tubing, the stuff that's used in the engine bay.

Something like this might work: elbows on the vents:



Then some T-connectors:


All connected by short sections of vacuum tubing. Should work, as long as the c/c of vent spigots is greater than the length of the T-connector's main section.

^ Hopefully the price of all these pieces doesn't end up rivalling the OEM part, lol. If that was the case, a simple tube with holes drilled in it at the vent loc's would be a lot cheaper. When drilling the holes, maybe put a slim dowel inside it, to prevent the tube collapsing as you drill? Or not: small diameter likely pretty stiff, if you drill slowly.

 

Yes this. Like I said, my 12V battery is very similar to yours and has given me no trouble at all. I know that 12V batteries can get a bit of a sulphuric acid smell if they are overcharging and gassing a lot, but with your 12V battery in good health and the charging system working correctly, that definitely won't happen. Besides, from the description of the smell that most people give it doesn't sound at all like the sulphuric smell of a gassing lead acid battery anyway. So I'd say you're looking in wrong direction by worrying too much about the 12V battery.

I think it's the tubes on the HV battery, that's the cause that others with this problem have discovered. Just why some Priuses get this problem of these rubber tubes degrading, while most don't get a problem, I don't know.

 

pm brit prius for his source.