Prius's spontaneously catching on fire?

Just two months ago, BMW recalled over a million vehicles for fires from an electrical problem that can happen while the car is parked cold. Really cold, e.g. freezing. Long before that, Ford and other makers had to recall vehicles for electrical problems in switches (ignition, windows, etc.) and electrical connections that burned parked cars. Some of these involved large numbers of actual fires.

If you suspect that your case involved a vehicle defect, you can report it directly to NHTSA:
File a Vehicle Safety Complaint

 

Just within the last 5-10 days we had a post about a electrical fault someone had on a Prius. I cannot seem to find.

@fuzzy1 On the BMW it would be interesting to hear specifically what cold do to cause a fire

 

our last hycam was recalled because the window switch mechanism on the drivers door could short out if opened to the rain, potentially starting a fire.
nothing to do with the hybrid part of the vehicle to my knowledge.
of course, it probably happened once, so all have to be reworked.

 

Didn't the fire department have any opinion on the source? The pictures don't show the engine compartment, which I take to mean that it wasn't the major damage area. The trunk hatch appears to be missing, which would indicate the trunk area as a problem. Anything in the trunk that could have started the fire?

 

With Ford, it was hundreds of fires from the ignition switch problem, and hundreds of more fires from the later cruise control switch problem, and many recalls.

Honda's fires were from a window switch problem, though I don't see numbers at this moment. And yes, other makers have had similar fire problems and recalls.

 

Only the hybrid battery. They think that's what happened to mine. It had been both serviced and inspected about 2 weeks before the fire.

I also have pictures of the car's interior, if anyone's interested.

 

That's not a "hybrid battery" or a "Lithium Ion" problem.

If this happened right after the car was serviced and inspected....then I'd be curious as to what they were "servicing."
Priuses are involved in fires, but probably to no greater or lesser degree than any other passenger car - especially 12-year-old cars.

Glad nobody was hurt!

Good Luck!

 

I do believe Prii are involved in more fires than Teslas.

Which is to be expected, because the Prius is still a gasser, therefore subject to the same fire problems as other gassers. Hundreds of gassers burn every day.

 

That's true, but remember how many 2007 Tesla cars that are NOT on the roads these days.
Reliability rates for battery packs degrade over time, and with the loving attention of mechanics OR lack thereof.....

I'm a submariner.
We don't like gas engines NOT because we're hipsters who like to invent cutesie names for stuff and look down on other people, but because the first submarines WERE hybrid 'gassers'....like, with gasoline engines.
We've evolved past that, and the diesels that replaced those, and nucular will probably give way to AIP, and then autonomously powered fuel-cell or pure electric.

However.....(COMMA!)
Submarines have always had big honkin' batteries in them....and I have a submariners instinctive respect for what happens when something goes wrong with big honkin' batteries....

It's like "gassers".
Safe....as long as you remember that it's dangerous.

 

<bump> I will refer you to this thread regarding the HV monitoring system in Gen I Prii.
The battery fires at ECU sense connector thread | Page 7 | PriusChat
No idea if it is relevant here. But I point out:
The HV monitor lines are connected to the battery ALL the time, so IF (hypothetical) a conductive path can form either internal to or on the surface of a connector, current can flow and cause issues, up to and including fires.
I own only Gen I Prii, and I have observed some incredible levels of charring on the connector between the battery harness and the HV ECU in the battery itself.
How long does it take to form? No data.
Me personally, I think it should be an annual inspection item for owners (and Toyota); but the HV Monitor connector is "inside" the battery case, which says (metaphorically) "No User Serviceable Parts Inside, So Don't Bother to Ever Look".
Just sharing information...

 

<bump>
pointer to data (from 2019) on vehicle fires.
Baseline: 2018: 111 million automobiles registered in the US,
and 275 million total vehicles (cars, trucks, snowmobiles, etc).
<edit> my memory tells me the average age of an automobile in the US
is on the order of 12 years. Interesting statistic would be #fires by age of vehicle.


Vehicle fires

 

We're doing a lot better than a few decades ago:



... though the improvement seems to be leveling off.

Says the leading causes were mechanical failures or malfunctions and electrical failures or malfunctions. Makes me wonder what other categories they had.

 

Chap, the really interesting statistic is # vehicle fires by vehicle age. I'm still looking for it.
Properly done, it's (# fires) / (# vehicles from that year on the road).
How long does the neoprene (or whatever flexy plastic used in vehicle fuel lines) stay plastic before it splits?
In the old days, why would people replace spark plug wires? Ans: engine heat & time caused them to crack.
Tires, even if unused, eventually dry-rot... 5 years or so.
FWIW, I'm thinking my HV ECU connector charring took place over 10+ years.
So for Gen I drivers (yeah, a vanishing breed), should be an annual inspection item.

 

My guess about the HV ECU connector (though still a guess; I haven't watched it) is that the charring itself didn't take 10+ years.

My guess is that the growth of somehow conductive material on some of those pins (either the malachite seen growing on many of them on the same two pins, or tin whiskers from the pin plating) grew over 10+ years, and when it finally made a conductive path, the charring happened pretty fast. It might also burn away the conductive path and be self-limited, but repeat again later.

I did see this in the NFPA report:

"Highway vehicle fires were more likely to begin with the ignition of electrical wire or cable insulation than any other specific item."

Tires, I hear, don't like to be unused. Rolling redistributes some protective waxes/oils that can be degraded at the rubber's surface, so they deteriorate faster if unused, especially if exposed to the elements and sun.