Loss of Power on Canyon Road!!!

OK - wasn't sure where "So Cal" was?

 

If the traction battery over heated it would have set off a code! Driving with foot on brake pedal cancel out any attempt to engage the traction motor or ice. but then you was able to drive 18 miles up to 3 bars, backup lights on? sound like there some serious electronic problems! do you drive using right foot gas only and left foot brake ?

 

OP is in Southern California. I'd be surprised if he found snow yet.

 

Might have been better if you had had it towed. By driving it you might have reset the invisible trouble codes. Grinding noise a bad cooling fan on one of the computer boards cause heat related errors? (do they even have fans?) Grinding or buzzing? Buzzing could be a bad relay.
There is a thread about a Gen3 going up a hill in New Mexico I think that had power problems do to some bad power IC chips in the inverter/charger over heating. Can't recall if it caused fault codes or not. If the generator motor can't reliably send excess power to the hybrid battery you might have drive issues like you describe.
Gen 2 inverter cooling pump type problem?
Have them test the 12 volt battery and charger also. Bad/intermittent 12 volt system can cause some bizarre computer/electrical symptoms.

Problems like you describe are few and far between.

 

That's makes sense. It's odd that the 2nd vent is not mentioned in the owner's manual.

My 2nd vent is not in the middle, like shown in Alan's photo. Mine is on the far left side. It's long and skinny, and partially obscured by the lip on my rubber floor mat. You wouldn't even know it's there unless you were looking for it.

Vintage Pep's incident, is just another example of why I consider the Prius to be "complicated." Unexplained, weird things, that can only occur with a Prius. I've had a warning pop up a few times when simply shifting into "D", drive. The car won't move, and one time all the power cut off. I think I saw this on the screen... "!"

 

Maybe the "2nd" VENT is in different places according to the battery which could be a different shape - mine is NiMH - what's yours?

 

Hi Alan. I have the new fancy Lithium-ion battery. But it is supposedly smaller, and located on the right side by the big vent?

We may NEVER know what that 2nd vent is for. I try to not keep anything on the floor back there... don't want to block any air flow.

 

If they didn't find any problems or fixed it! take it back to the dealers ship it was purchase, kindly explaining the problem, and concerns of your safety ! ask them kindly to have their tech or some one to drive it for a week or so , it needs to documented! otherwise just trade it in for something else of your own liking and take the loss but gain a piece of mind!

 

Does anybody remember this limp home issue on the prior generation:

Toyota Recalls 1.9 Million Prius Hybrids Over Software Flaw - IEEE Spectrum

I lived with a Saab intermittently going into limp home mode towards the end of its life and It was very disconcerting to say the least. Those symptoms were very similar to what the OP described.

 

One of the fun games my Jeep Commander played with me was the drive by wire throttle going crazy. Intermittently I'd get what sorta looks like a lightening bolt error on the dash and I would lose all throttle control, it'd drop to an idle. I suppose that's better than going wide open but it happened to start occurring 500 miles from home in Utah on a holiday weekend. I finished my trip (stuck to the pavement sadly) and then limped home. Every now and then it would cut out then a second or two later be fine. this got worse and worse, cruise control quit working, then eventually the ABS and traction control systems failed and I got a "service 4x4 system" message. I do get it home without much drama, just the occasional "come on big girl!" When I got home I let it sit over night, started it up the next morning, no issue, hooked up the code scanner, no codes. Drove it for a week, it was fine, next week it started again. Immediately hooked up the scanner got a code about a brake light being out. Confirmed my brake lights were fine but that got me looking at my brake pedal switch. It was a bit dirty, but nothing dramatic, new part was $15 or so. Well I took it out, turns out AutoZone had to order it, so I went home, cleaned up my old part a bit, put it back in.... everything has been fine ever since.

I drove that thing a lot with muddy and dirty shoes. It's like not there was mud on the switch, but just a bit filthy with dust and crud. My theory is the switch was sticky so it wouldn't come out from time to time when I let off the brake. That would throw the drive by wire throttle, brake lights, traction control/abs and awd system into a fit. If you're someone who drives with two feet in a modern car you're probably going to have strange problems.

 

I think that the phrase that pays here is: Canyon Road.

If the batts overheat, you're going to throw a code.
Actually? I thought that forcing the vehicle to go into limp mode would too....but I have an old G3 and it was built before octogenarians started confusing one pedal with another causing SUAs.

OP:
Do you drive with only your right foot, or do you sneak a left foot into the driving equation every now and then?
No offense intended, just trying to solve the riddle.

Also: Is this mysterious Canyon Road filled with curves?

 

The lack of error codes is really odd. As MrMischief said, I would check the brake pedal sensor and harness. If there is a problem with it, it would explain the behavior of your car. Brake should override the accelerator in a drive by wire car as the Prius. Try to start the car without pressing the brake pedal. If you can do it just once, take for sure there has to be an issue with the brake pedal.

Nexus 10 ?

 

About two weeks after I purchased my car, I ran into a squirrely situation. The battery drained to one bar and would not go into regenerative mode on a steep downhill grade right before I reached town. I did my shopping and everything was fine on the return trip. I haven't given it much thought since because it hasn't happened again. I figure there are a lot of things that I'm not familiar with and if something only happens once or I can find an explanation, I'm okay. If it becomes a standard thing, I'll have it checked out.

 

The one bar situation can be caused by many actual problems or a true fault. But once you have 1-bar, you will have very minimal battery just as the OP described which all sounds normal for an overheated battery except for when it finally died.

I can say that something similar happened to us a couple months ago. A Lexus RX450h which is essentially the same as a big Prius driving down the road, then the battery discharges, power lags, and within a couple minutes, dead on the road.

Turns out sediment in the gas tank killed the fuel pump and that's what happened. It's one of those problems that is not electrical or common in nature, so the ECUs don't have any idea what's going on to throw the right codes.

 

That's interesting - ½ dozen "simultaneous brake and accelerator" within 13 minutes - wonder if it's a fault occuring if you only did it once yourself.

Then between 22152 miles and 26504 miles there were 4 "SUDDEN BRAKING HISTORY" and 5 "ABS OPERATION HISTORY" logs. There were none of either of those before 22152 and after 26504 (and during those times there were no logs of "ACCELERATOR POSITION ..."- which, unless your driving style was dramatically different before/after 22152, it indicates the car has been doing something different.

An ABS fault?

 

HMMMMMM....
It's starting to smell like a TLA problem rather than a cockpit problem.
By TLA, I mean Three Letter Acronym. TPS....BPS...ECU....VSS etc.

Since the Prius if fly-by-wire, you have the advantage of some bread crumbs to follow.....but....since the G4 is a FYM (first year model....in keeping with the TLA theme....) you may be out on the sharp end of the stick with a desingn problem.
New Pintos never caught fire back in the day!
People had to drive them some until they weren't new anymore.
If you think that this might be a safety issue (2 child seats in the car?) you may want to loft a report to the NTSB, and inform whatever bureaucratic workers at Toyota Customer (Don't) Care that have you on "ignore" at present that you have done so.
File a Vehicle Safety Complaint | Safercar.gov | NHTSA

Remember the octogenarians and the SUA reference earlier?
Well, Toyota had to pay up for that one even though (IMHO) they were COMPLETELY blameless for the SUAs.

I'm thinking that saying "NTSB" at a Toyota dealership is a little like saying "I smell SMOKE!" at a Tesla dealership, or "Hey! The FBI is here!" at a certain unnamed political campaign HQ.

.....really gets their attention!

Good Luck!

 

i have the same problem with my Prius 2016, live in Monterrey Mexico, it´s been with the deales for two months and still no answer, it has only 3,000 miles. Was your prius fixed? Please let me know if they gave you a solution, it´s the same problem.

 

TWO MONTHS???! I think I would tell them to just keep it!

Or is that post a joke....