Long-term reliability of electronics in Prius

That's a good way to look at it. You'll be saving some amount of money in terms of fuel and maintenance. I don't recommend extended warranties. I would take that money you'll save and self insure. If you have an alternate mode of transportation, then there is no worries about a major breakdown. There is only one reason to purchase extended warranties and that is for peace of mind. You seem to know your way around cars. I'm no where near as knowledgeable as you in car maintenance. I didn't purchase an extended warranty because I can work out something to share my wife's car temporarily. Statistically, Prius is one of the most reliable vehicles on the road so I know I'll come out ahead self insuring for repairs.

 

Agree!
Regardless of cost issues I could not justify buying anything other than the most fuel efficient vehicle possible for environmental reasons.
Have built an ebike for the around-town errands and small shopping excursions, though, rather than using an old motorcycle.

 

"Built an ebike"? Wow, you are ahead of me on that. I think this merits a private conversation (as it is OT-off topic) as to what that is and how to do it!

 

Extended warranties are basically "insurance policies" for those who cannot afford to self insure.

You are basically pre-paying for the repairs that you might need. The insurance company wagers that you will NOT need the repair (which most will NOT, you are betting that you will.

Since most will NOT need the repair, the insurance company usually wins and keeps your premium as a profit.

If you save your money, and like most, you will NOT need the repair, you KEEP all of your money with interest in savings. If you do need the repair, you just pay for it with CASH.

The nice thing is that cash insures more than just the one car.

 

One nice thing about the Prius models is that they made lot of them, especially the Gen II's and Gen III's.

Because they very reliable, many NEW surplus parts remain in Toyota's inventory, and many used parts are very reasonably available. I'm almost sure that Toyota explores and evaluates the costs of used, and as I have witnessed, the price of the NEW part for older models go down in price accordingly. Toyota, like most business, doe NOT want to store a large quantity of "NEW OLD STOCK."

That's another reason why the cost of keeping and feeding low volume add specialty cars cost so much more.

 

My first-generation turns fourteen this year. I've put about 100,000 of my miles on it, on top of the 126,000 on the clock when I bought it. Maintenance-wise, I've done two wheel bearings (say $400 total), a front brake job and stabilizer links (roundly, $250?), three light bulbs ($12) and a shim kit for the A/C compressor clutch ($1.21). You can save that last expense with a Gen 2 or Gen 3 because their electric compressor doesn't need a clutch. Oh, and one trace repaired in the rear defroster (free, because I already owned the silver paint). Plus normal scheduled stuff, hmm, 24 oil&filter changes ($720), 4 coolant and transaxle oil changes ($120), a few air filters (engine and cabin), say $50, set of iridium spark plugs ($40), wiper blades a few times ($60), and a V belt ($11.48). That last you can save on a Gen 3 because the electric water pump has no belt. Probably $1200 in tires. Over 7 years, that looks like about $400 in maintenance a year. Toyota changed an expensive steering rack for me, 7 years and 140,000 miles past the end of the original warranty, because they realized it affected lots of owners.

Ah, but you can. There's the beauty of it. Sounds like you and I are close to a certain age (my first car was a 1972, but that's not when I got it). Sure, I remember how it was ... the sun, the sweat, smell of warm oil, click of a wrench. Sweet memories of favorite destinations brought to mind as their fragrant soils sifted gently into our eye sockets while we squinted upward from the creeper. Snarl of the intake with the air cleaner off for carburetor adjustment. How quickly I knew I could pull the valve cover (aluminum, cast, two bolts) off that 4G32 engine any time I wanted to reset the valve clearance. Sacred hand-me-down techniques for tracking down sneaky vacuum leaks. The ecstatic feeling of accomplishment in figuring out how in blazes something worked when it was a whole subsystem the car had that wasn't even shown or mentioned in the Chilton manual or the Clymer.

But as we approach a certain age, it's ok to start to appreciate another kind of game. A kind that can be played largely in a comfortable chair with good light, fingertip access to the genuine service manuals complete, computer diagnostics that, interpreted carefully, can save hours of time figuring out the problem, and a cold drink. Then just a bookmark's click over to the full dealer parts catalogs and diagrams at Metro or Village Toyota (like, when was that ever a thing you could do?), where you find the exact offending part and arrange for it to arrive on your doorstep. When it does, you walk out to the car with the part and the exact six tools you know you'll need, and when you're done fixing it you come back and finish the still-cold drink.

Imagine, say, a pump from the old fragrant days.

A motor, two wires (+12 V and ground), a relay to start and stop it. What could be simpler? If it wasn't pumping for some reason, there was plenty of daylight left at the shade tree to dig in with our meters and start trying to find the problem. Is the relay closing? Is the pump getting voltage across it, but maybe not enough? Is that because of a problem in the 12V supply? Bad relay contacts? Or is it on the other side, and the ground connection is bad? Does the voltage only look inadequate, because what's really happening is the pump is locked and drawing too much current, pulling down the supply? Or is the supply OK and the pump is drawing too little current, maybe because the brushes are worn? Nothing complicated here, just simple elimination, and with enough persistence, ruling the choices out one by one, digging down to the right wiring connections to tap in with the ol' meter and test each idea, we were pretty much guaranteed to track it down to the root problem before dark.

Now a pump from the cold, soulless Prius days (2001 manual, page DI-417):

Egads, what's wrong with this thing? It's got more wires on it than a character in The Matrix. What kind of nut thought a pump needs seven wires? And a built-in resistor? What's up with that?

Ok, for starters, it's not that bad really; the connections at the bottom are just ground and those at the top just 12V from the relay(s), as before. They're both doubled up here because this is no aquarium bubble pump.

It's those white-blue, yellow-green, and yellow wires off the side that are something new. All three of those run straight back to the computer. It just watches them. That's the only reason they're there.

What if this pump isn't pumping for some reason? Not getting 12V? All three sense wires at 0. Bad ground? All three high. Poor connection upstream? All three low. Pump drawing too much current? White-blue pulled low, yellow-green rises. Pump tired and not drawing enough? White-blue stays high but yellow-green rises less than normal.

To find out which of those possibilities the real problem is, you ask the computer and it tells you. It's been watching those sense wires all along, so it already knows. Then you go straight to that area, find the culprit, and fix it.

So for sure in this new game, you don't want to show up without the tool for asking the computer things. That's now just about equipment necessity #1. Also important, access to the manuals. The scan tool may add little one-liner descriptions to what it gets back from the computer, but often not enough that you'd know what to make of them if you didn't have this picture in front of you. Once you do, you can sit in the comfortable chair with the cold drink and piece together the evidence until the aha! comes.

I could be accused of overselling somewhat. The computer here has not told us exactly what the problem is and how to fix it. Suppose it said the ground is bad. There's still old fashioned poking around to find out where and why. Whoever expects the computer to give all the answers will feel baited and switched when it can't. In this case, all it has done is instantly ruled out four whole areas out of five and indicated the one to focus on. But that helps a lot, especially if the sun's getting low.

So it's not so much "need a computer to figure things out" as "can use the computer to figure them out way faster than you ever could otherwise."

One thing that's true is that the new game will feel unwelcoming and impenetrable to a person who's all closed off to learning new ways to play. If someone is offended by the computer and won't ask it questions, then they pass up all the time they'd save by finding out what it knows, and end up just trying to poke around the old way, and getting all frustrated about these stupid pumps these days with their half dozen wires like dagnabbed Medusas. Ironically enough, the extra wires are only there to be a huge help in diagnosis, but to someone who's ignoring that help, they're just in the way.

So, yeah, the game changes a little, but only to the kind of game you might appreciate these days if you gave it a try. Pour that cold drink, sign up on techinfo.toyota.com and find that comfortable chair. Your days of doing your own work don't have to be over.

-Chap

 

The best and most reliable and least complicated cars were most likely made between 1989 and 1999 before the advent of the current complicated electronic systems.

The best developments are apparently electronic fuel injection, electronic ignition and emission controls.

 

Which mini-VCI brand would you guys recommend for me to play this game?

I think the best development was the Jet Assisted Take Off unit !

 

I happen to own a 2010 Prius III, 85,000 miles on the odometer, bought in December 2009. (Note: This is shortly after the first wave of improvements, so I got a cargo cover in the back for no charge.)

Repairs:

1. Idiot at one Toyota dealer half tore off the plastic oil change cover when changing the oil. Replaced after complaints at a second dealer. No problems since then.
2. Idiot at the second Toyota dealer, years later, over torqued the oil filter cover. My attempts at getting it off punctured the cover. My $ to replace it with a new cover.
3. Two recalls:
   1. Brake controller. People had been complaining that, when the car was slowing down at low speeds on a slippery surface, the switchover between the regenerative brakes and the mechanical brakes didn't cut over fast enough. The recall sped up the switchover.
   2. Inverter controller. As others have mentioned, a very few Gen III Priuses had blown transistor problems. The update reduced the stress on said transistors and Toyota extended the warrantee for near forever.
4. Headlight bulbs gave out around 65,000.
5. 12V Lead-Acid battery gave out around 70,000.
   
6. One front running light gave out around 83,000.

That's it. Period. Others have complained about rattles. I get a few, barely noticeable ones in cold weather. I'm on the second set of tires after the first ones wore out at 40,000 miles. Oil changes every 10,000 miles. After reading some comments on Prius Chat, swapped out the transmission fluid around 45,000 with new, and, at the dealer, did it again at 85,000. Other than that, just followed the service plan.

Cool note: Asked the dealer to check the brakes. Factory fresh the pads had 12 mm of thickness. They now've got 3 mm to go before they need replacement. That means the car will be around 120,000 miles before the first brake job, assuming nothing else goes wrong.

All right. At work I play part-time reliability engineer. There's this thing called FIT rate, which stands for Failures in 10**9 hours. A single resistor on a circuit board has a failure rate of 1 FIT, which means that if one has 1,000,000,000 resistors in a system, one will get one failure, on average, per hour. An average high-density integrated circuit has a FIT rate of around 100; a switching power supply, around 300.
These failure rates are considered to be the rates one gets between infant mortality and wear-out. They're Poisson distributed, which means, randomly distributed.

As a random guess, the FIT rate for the electronics in a random Prius is probably on the order of 50,000 to 100,000. Let's use 100,000 as a number to start. Let's see what we get for the number of failures per year. First, FITs only work while the car is in operation. Let's suppose the car sees two hours of operation per day, on average. Then, with 2 x 365 = 730 hours/year, we get
Prob_Failure = (100,000 Failures/1e9 hours)*730 hours/year = 0.073; so, there's a very rough 7.3% chance of any random Prius failing, after the initial infant mortality. My numbers are very rough; I once estimated a Gen II controller at around 15,000 FITs, based upon the chips I saw there; but the total electronic FIT rate could be around (minimum) 30,000 or so.

True electronics wear-out usually takes at least 5-10 years. Silicon at vaguely normal temperatures has a wear-out time measured in decades, if not longer. North of 100C it gets a bit more interesting, but that's why the inverter's got coolant, and there's a reasonable guess that Toyota could have made those transistors high-reliability types, given the environment. Other things that die more-or-less like lightbulbs would be electrolytic capacitors but the right types of those could go on quite a whiles.

However, what all of this is saying is that, while possible, it's not likely that it's going to be the electronics that takes down a random Prius: Rather, standard mechanical wear-out in the engine and attached devices or perhaps the expected decline in the traction battery performance would lead to major expenses.

I note that there's not too many web sites around that concentrate on Priuses. We do get the occasional person complaining about a brake system failure, or limp-to-the-side-of-the-road inverter or other failure, but they definitely don't show up in crowds.

Finally: I suggest that you chase over and snag a copy of the Consumer Reports auto issue, issued just this last month. In the back they have tables of data from their readers about the reliability of their cars. You'll notice that the Prius Gen III cars (sorted by year) are almost solid red dots, denoting well above average reliability. Look up Jetta's and other European cars... There's a lot of black dots (well below average reliability) all over.

KBeck

 

I'd say the car electrics are fine. It gets cold and damp here, especially in Autumn and I've had dew on the inside of my car - as in thick dew that forms droplets all across your dash. The car steams up too when that happens and it has happened a lot in certain weather. The electrics have been fine and seem to handle it.

Now Citroens and French cars are a different matter. They work fine in warm, dry France, but give them a cold, damp, English autumn morning and they're just an overly large paperweight.

In other words - don't worry about it. The car will be fine.

 

My first post... hello everyone...

My 2013 Prius stereo (with NAV) does randomly restart, about once a month, for no apparent reason. I've kept logs of the status of the system when it has occurred, such as in EV mode with x battery remaining, or accelerating or decelerating... I can't determine what is causing it. That is the only issue I'm having... this is my first Prius and I'm totally in love it...

 

First thing to check is the condition of your 12v battery. When they start to fail one of the first things to go are the radio presets. The 12v in a Prius normally lasts 5 years/80k miles (with exceptions both sides), but they are small and can be damaged if allowed to run down too low.

Has you just purchased the car? Has it been sat on a dealers lot for 5 months? Do you do lots of short runs? Do you use Acc mode to listen to the radio or using a tyre compressor pump? Have you tried to jump start a neighbours car (which you shouldn't in a Prius)?

Check your 12v. If you're able try and charge it up off car. See what happens then. The 12v isn't that expensive to replace.

Welcome to the forum.

 

So, you've got an issue. No surprise there. Going back to my rough numbers du jour, there's wild handwaving guess that any given Prius has a probability of electronics failure in any given year of somewhere between a 2% per year and 7% per year. So, suppose we have 1000 Priuses in a population, which is enough to actually start taking some statistics upon. This would then imply that in 1000 Priuses, somewhere between 20 and 70 of them pick up a fault in any given year.

However, it's even better than that. Calculated FIT rate numbers are known to be biased in favor of failures by a factor of somewhere between 10 and 2, with various PHDs throwing textbooks at each other taking one position or another. So, going for the factor of 10 end of things, that would imply in our population of 1000 Priuses, somewhere between 2 and 7 of them fail in any given year.

Prius Chat is a lively place, but not everybody believes in talking on-line about their car; at best, I'd bet that the number of people who actually show up here is perhaps 1% (probably less) of the total number of owners out there. But, if we got 1000 people in a population all of whom own Priuses, the statistics should come up the same: one in a thousand should experience a real fault. Or maybe 1 in a 100. And with a nickel, I betcha that would match what one sees in the posts around here.

KBeck

 

As with any vehicle, the choice to buy an extended warranty is just that, a choice. The money is already spent and you move on to the next thing in life. The often said comment of putting the money in the bank "just in case" sounds good on paper, but life has a way of throwing other fires at us that find that stash quickly. While the Prius (at least mine) has to be the most trouble free vehicle I've owned "ever" so far, that doesn't mean everyone's will be.

I am of the thought that if you don't know how to fix cars yourself, or don't have the money for possible outside warranty fixes, you should consider one...but this is optional insurance and not required, and the price is negotiable. It's a choice only the purchasing party can make.

 

And if you bought an extended warranty, one thing is for sure: that stash is empty.

 

Depends on what breaks and what "policy" you buy. Like the human body, machines break too. That's why we both have jobs.

 

Ah, there's your trouble ... you're wanting to fix all the stuff you used to have to fix that either don't exist in a Prius or scarcely ever need attention. Points, condenser, rotor, ignition wires ... none of those, direct coil-on-plug system. Plugs themselves ... iridium tips ... twice a decade. Adjusting the timing ... hmm, to do that, you used to have to grab a timing light and watch a degree scale that was machined partway around the crank. Now that scale is just machined all the way around the crank and watched constantly by the computer instead of occasionally by you, and the timing is always right. If it isn't, the crank sensor is bad, so you put one on that isn't, problem solved. Also, the computer can watch those crank marks fast enough as they go by to notice how much the crank speed changes between piston strokes - if you've got a misfire problem for any reason, it can tell you which cylinder.

Rotors, pads ... I was taking occasional measurements of pad thickness to project out when they would hit the minimum, which was coming out roughly 2018. However, I should have been a little more attentive because even though the pads wear very slowly (because so much of the braking is done by regen), other stuff like corrosion of caliper slide pins or cracking of boots does still happen, so I did end up having to turn rotors around 200,000 miles and sadly replace the pads that still had almost half their linings left. I probably could have avoided both if I had at least flipped up the calipers and checked boots and slide pins more regularly, it would have taken mere minutes. I also have had to change two wheel bearings, as I mentioned. I also need to change the driver door electric lock actuator.

For a while lately I've noticed some disconcerting gronching noises as I go over certain uneven terrain, and was wondering if it was the beginning of the end for body integrity, but last night I noticed my driver door hinge is worn and quite possibly all the noise I'm hearing stems from that. Door hinge is on order.

Edit: I should have followed up on that. Hinge arrived, I installed, problem solved. I was worried about some kind of significant body problem developing, nope, gronching sound totally cured, sounds tight like new car again. One hinge, four bolts, done.

That's interesting ... my 1972 Mitsubishi gave me plenty of diagnostic opportunities. It came to me because the former owner decided enough was enough when the radio began blinking if the turn signal was on, when it was no more than five years old. Body rust was a big factor ... wiring harnesses have ground points attached to the body at various points, and when those parts of the body start not being attached to other parts, electrical behavior gets funky. Another common cause of stuff not working was the wiring connectors, which were more open to weather then, and could become pretty well nonconductive without their appearance changing. Those took time to track down. Car makers seem to have made huge strides since then, both in body rust resistance and in weather resistant electrical connectors. I could mention Toyota's wiring diagrams provide the level of detail to see just how every harness is routed in the car, and every ground point in every harness and where it attaches to what. Not that I've needed any of that yet; the car has been completely free so far of any of those bad-connection/bad-ground mysteries I used to be able to while away so many hours tracking down.

My dad bought a used Ford LTD once knowing the taillights didn't work, figuring it would be something simple and I'd find it for him. It was simple, in fact: the dome light circuit ran back along the driver's floor edge, up the C pillar and over to the center of the roof. An unfinished sheet metal edge at the top of the C pillar had cut into the dome light wire, blowing the fuse. The previous owner had fixed the problem by installing a 30 amp fuse, melting the entire wire harness from the instrument panel back to the trunk into one solid gob.

One time I was pretty worried because my engine was running rough and also making a horrible screech. The old timer I asked for advice recognized it instantly. I had had the carburetor off so many times for one reason or another, without always using a new gasket below it, that I had mashed the gasket quite flat, and it was (a) admitting air and (b) acting as a clarinet reed. Probably not something you'll encounter with a Prius. There just aren't as many reasons to ever fuss with the Prius throttle body as there used to be for fussing with carburetors. You might end up wiping it with a rag with throttle body cleaner every now and then.

There probably hasn't been a better time. History has sort of gone through (a) cars without very sophisticated electronics (but made up the lack with hugely baffling mechano-pneumatic-hydraulic things like carburetors and auto transmission valvebodies), through (b) cars with electronics getting more and more elaborate but still not sophisticated enough to give you any help with diagnosis, to finally (c) today's cars with electronics sophisticated enough to watch over what's going on and tell you when you ask. (b) was a really good period in history to sleep through, if you got the chance. (c) is pretty cool. Also, Toyota's manuals are super thorough and informative, and having them all online without a prohibitive price tag can really help you out with the car.

Cheers,
-Chap

 

Well Chap,
You have cheered me. What with the arthritis in my hands, the pain in my right shoulder, and my stiff knees, perhaps learning electronics will at least preserve my brain. Plus the help to my immune system at the laugh I got about idiots who replace blown fuses with higher amp ones (I know enough about electricity to not do that one.) and the picture I got of the meltdown!

So, how do you read the computer messages without the expensive diagnostic machine the mechanic has?

Oh yes, and before you replace the door hinge, try some Lubeinatube. Took care of the sticking/popping hinge on my 21 yr old Dodge Ram 2500 truck.

Goatie

 

Minor quibble: new brake pad thickness is 10 mm, not 12.

Also, you say they've got 3 mm "to go": minimum thickness is 1 mm, so they're at 4 mm now? Or 3 mm? That said, if I knew the pads were around 2~3 mm, I wouldn't put it off for long.

Also, pad thickness aside, there's caliper pin lubrication, they're gonna be pretty dry by 120000 miles.

Brakes are not meant to be ignored until the pads warrant replacement. Even with plenty of thickness it's worthwhile periodically detaching the caliper and rotors, cleaning/checking, and relubing aforementioned caliper pins.