Battery issue if left at airport

I too bought a jump box after the Prius was left overnight with its interior lights on --- miles from home. I did notice that it took a few minutes to charge the Prius 12v battery before I could re-start the vehicle. And I was jumping it from a vehicle with a full size 12v battery. A consideration is that the jump boxes are designed to provide high cranking amps, while they have fairly poor reserve capacity. So if you're buying one, go a bit over size.

 

When jumping, be sure to follow the recommended sequence found in the owner's manual...



Reverse the sequence when disconnecting.

 

Don't listen to anyone that says the 12v battery will last more than 2 weeks. IT MAY NOT! This according to an experienced mechanic at the dealership. They have a service bulletin which I have a copy of which shows how to disconnect the "short pin" in the fuse box (it is white) if storing more than 2 weeks. Bad engineering I' say.

 

After we bought our Prius V, some neighbors purchased a used Gen II Prius - they have had three batteries replaced in under a year.

The Toyota folks have told them they do not drive it enough, and they will continue having these problems (they are elderly, he doesn't drive anymore, she drives 4-14 miles round trip, though not on a daily basis, with occasional 200-300 mile trips). Their last occasion was when parked at the airport for 10-12 days.

This seems not right to me. Your suggestions, including what to have Toyota test in the charging circuits, are welcome so I can pass it on to my octogenarian friends.

 

How often do they drive? I don't drive on a daily basis either - I often go at least a week without driving. And when I do drive, it's not very far.
Have they ever left a light on or drained the battery somehow? Do they use it in accessory mode (e.g. to listen to the radio)? Draining the battery even just once or twice can permanently cripple the battery.

In my first year of ownership, I only drove about 6,000 miles (mostly on weekends), drained the 12V battery once (never figured out how - it was just after I hooked up my ScanGauge though), and didn't have any problems with it (nor in the second year, now).

One difference between the 2nd and 3rd Gen is that the 2nd Gen doesn't automatically put the smart key system in a low-power state after a few days. If most of their battery problems occur after the car sits for several days, they might consider pushing the button far under the steering wheel to disable the SKS, at least for those long periods of inactivity.

Beyond that, I have no idea what the dealer should check, but perhaps they should try a different dealer if theirs isn't willing or able to find the true cause.

 

Thanks, macman408 . I will pass on the SKS deactivation button and ask them if they are perhaps leaving an accessory on. That's a good start, and if that doesn't pan out I will advise them to have another shop do some diagnostic work.

 

The Gen II Prius does indeed automatically disable the SKS after a period of inactivity. The difference between the Gen II and Gen III is the number of days. It has been shorted for the Gen III.

Tom

 

It is bad engineering to use a smaller (and much much lighter, for your continued better mileage per gallon) auxiliary battery that doesn't have as many loads or tasks as a non-hybrid vehicle (such as cranking over an engine?)??

It is as much size and capacity of the battery as it is how sensitive the many PCMs are in the car to having a steady supply of over 12 volts to operate the vehicle and start charging the battery, unlike a conventional vehicle, where voltage is fed back to the battery as soon as the engine starts to turn over..

 

I left my vehicle at Los Angeles International Airport for 6 weeks, and my vehicle started immediately. Although, I have other undetermined engine start up issues I need to discuss with our local dealer. Specifically, it was unusual noise or vibration.

 

My grandmother only drove her 1977 Plymouth Gran Fury on certain Sundays the last five years of her life. She would generally get a ride to church with a friend but in the event someone she couldn't set up a ride, she was driving albeit at 25 mph.

Since the vehicle was used so rarely, she had a couple times it failed to start. Now her church was quite crowded with a regular crowd. If you didn't get there early, you had to sit in the back pews. This was unacceptable. After all, think of the gossip. Why was Margaret late? Did she stay out too late the night before? Was there a man involved?

My father bought something called a Battery Tender. It was like a really small trickle charger that kept her battery topped. The plug for it was sticking through the grill. Once it was installed on her vehicle, she never was late for church again.

This wouldn't help at an airport, as you would need something like a jump box but anyone having this issue at home.

 

This begs the question as to whether anyone has used one of those small solar collectors to maintain battery charge while parked [outside] for extended periods. Is there a ready connection to the 12V system (cigar lighter or accessory connector) that is always on? If you can maintain a "full size" 12v battery from one of these collectors, it should do a dandy job on the smaller Prius battery.

 

No the cigar lighter is NOT connected with the ignition off. You will need to hard-wire the charger to the battery.

 

I think the cigarette lighter connection being made hot isn't a huge issue.

 

This plugs into the OBDII port.
12V VW SOLAR PANEL BATTERY MAINTAINER WITH OBD PLUG IC0915687D | eBay

 

it is going to depend on the battery condition, I have left mine for as long as 11 days and not had an issue. With a healthy battery and electrical system, you should be OK. But having the extra battery along wouldn't hurt (unless left exposed in the back hatch in sunny weather). You could also have one of those jumper boxes charged up. Or have your AAA card ready. Or most, if not all, long term parking areas are very familiar with this scenario and have the ability to jump start you from a van/truck or portable jumper. If they don't, I would say park somewhere else.

 

it is a valid point, for two reasons

1) If the car is only being driven short distances. When you start the car, you deplete some of the batteries availible juice, it takes a bit of driving to charge it back up and replenish that juice. If most of their trips are short, they may not be fully replenishing what they used up. And while I don't know the charging system of the Prius, there are vehicles out there that don't put out enough juice to charge the system at low RPM. That isn't a problem with a normal commute, but make it short, and all low speed, and you could finish with less juice than you started with. Do it often and you start to harm the battery.

2) Now if the car sits for a long time between drives the alarm and SKS system put a small drain on the battery, even the radio and clock do. for most of us, it is a non issue, but do it often and long enough and it starts to harm the battery, so it can't get 100% charged anymore.

Either of those things will shorten battery life a great deal. If a car faces both of those, then you can "burn" thru batteries fairly easy, even if the car is running right. What they can do to dheck that is to check the electrical load with the car shut off, is it correct or is it high which could indicate a short or drain somewhere.

Put it this way, on my car, I have a substantial commute, mine is an 04 with 138,000 miles on it, only on the 2nd battery (so the original and one replacement). My wife's Sienna, is a 2006 with like 63,000 miles, it is on it's 3rd battery. Why? Her commute is about 1.5 miles to the daycare, and then maybe 0.5-0.75 on to her job from there. Then at night it is the oppisate. So she only puts about 4 miles a day on the car, but with 4 starts. If we don't make an effort to drive the car on a longer trip at least once a week, the battery, even when new and fully charged, won't make it past Tue or Wed of the second week. She simply isn't driving far enough to charge the battery of the power she uses to start the car each time. So we actually use it when we don't have to, just to keep the battery topped off. So once a week I might take it to work, or we use it on the weekend to go somewhere with the kids or something, just to charge it up. Where the Prius would make more sense to use.

So your friends either need to hook up a maitenance charger for the car when parked at home, or let you drive it to work once a week. The first option is the better option.

yes, I have used them successfully in the past. I used to live on an island and left my car on the mainland, the little solar charger meant my car would start when I went on the mainland. I also used to use one during the summer when I would use my motorcycle to commute to work for weeks on end, wtihout touching the car. However that wouldn't work on the modern stock Prius, as the cigarette lighter, at least in stock form, is not "hot" when the car is turned off, so no charging can occur.

 

Sure it is, it means the electrical connection isn't there, whether you try to use the battery to power something or if you are trying to send power to the battery doesn't matter.

 

....hmm, my Optima 12v batt instructions for Gen-II recommended to disable SKS for long standing periods, so they must think the Gen-II auto-disable period was not effective.

I was thinking (from prior thread) that successful locking of car with SKS in operation implies all accessories off (good best practice). This implies, best practice if you intent to disable SKS (eg; gen-II) , then first lock via SKS and then unlock and disable SKS and check doors for locked status.

 

The Gen II Prius owner's manual also recommends disabling the SKS when the vehicle will not be used for several days. That's why the Gen II includes an SKS button under the steering wheel. The down side is that it causes problems when accidentally pressed.

For the Gen III, Toyota side-stepped the problem and just shortened the automatic disable interval, and then eliminated the SKS button.

Tom

 

how do you "accidentally" press a button that is up underneath the steering wheel?
More likely it was removed because so few people actually read their manuals these days that people who needed it weren't even using it, while people who somehow stumbled upon it would press it to see what it did, think it did nothing when they didn't see anything change, and then later couldn't understand why they couldn't lock their car.