Interior Light Left On, Get Into Car....doesn't Go!

[Rach73]

Hi, I'm new to this! I love my Prius!

I got in it this morning and found my 4 yr old had left the interior light on, since Saturday night! So this morning, it won't start the engine. The dashboard comes on, with all of the warning lights on. No screen info. There is a buzzer sounding when I have the door open with no lights etc on!

Does this mean the 12v is dead? And if so....what do I do? Can I jump start it like a normal car?

Please help!

[PeteB]

Hi Rachael

After that length of time the Battery is probably in a poor state, but if left for an hour or so it might just recover enough to start the car (the Prius needs much less from the 12v to get going, as it just works the computers and switches that connect the big Battery to the system. It's the big (HV - High Voltage) Battery that starts the engine and drives the car.

If not, although the 12v battery is in the boot, there are some jump start terminals under the bonnet. They are next to a fuse-box towards the back right of the engine bay as you look at it (i.e. the passenger side). You can connect a 12v jump starter or jump leads - red to the red terminal, black to an unpainted part of the car somewhere under the bonnet. If you left it connected a minute or two to breathe a little life back into your car's 12v battery, then try to start - good chance it will work. Then try to keep the car in REDAY mode for half an hour or so.

Be prepared though, if it's been flat for 2 days, the 12v battery may have died completely or be close to death (i.e. go flat very quickly) so keep an eye on it.

good luck, regards, PeteB

[Rach73]

Thank you thank you thank you! I appreciate your help x

[timberwolf]

Gen 3? I thought there was a timer on the later models to switch off the interior light after xx minutes?

[PeteB]

Gen 3? I thought there was a timer on the later models to switch off the interior light after xx minutes?

2008 model would be Gen 2

[timberwolf]

I can't see the posters details on this phone. I was working on 4 years back from 2014. For a Gen 2, the Battery ought to be flat.

[korat102]

Lead acid batteries don't like being allowed to go flat, if that happened it'll have shorted the life of the Battery considerably. If your 2008 Prius still has its original Battery it'll probably be near the end of its useful life anyway. Better keep a close eye on it for a few days and see how it goes. You can tell if your Battery is in poor condition before you have starting problems, the usual quick satisfying clunk when you unlock the doors turns into a lethargic chunk, that's usually time to recharge it...or replace it if it won't hold a charge.

[Rach73]

Ok, thank you so much guys. It does still have an original Battery so I shall start looking out for a new one! Any tips when I replace it?

I can change a wheel, but that's about as far as my mechanical skills go! (And it really scared me with a hybrid!)

Really appreciate your help!

Rach

[korat102]

If you're planning on doing it yourself, it's quite straightforward to replace the thing, though it's a bit fiddly and you'll need a few spanners/sockets. They tucked the Battery into a space in the right hand side of the boot (opposite the amazingly useful storage area they provided), at the back. Take the covers off and you'll see it nestling in there. The second gen Prius has a brake capacitor (a black box) beside the Battery which you'll need to unbolt and you may need to disconnect the main Battery vent tubing for access as well. That's the lump of plastic leading up from the area of the battery into the car, you can see the vent itself beside the rear seats.

Only two issues really.

First one is getting that main battery vent tubing top screw back in - you'll need to find some way to attach it to a screwdriver before you try. If you drop the thing (which you most probably will), it'll drop back behind the battery and you'll have to take the whole lot back out again to retrieve the screw - don't ask me how I found that one out.

Second one is that your 'automatic' one touch window will no longer work. You can 'reset' that by winding it down about halfway, then back up and holding the button for a few seconds after it stops moving. It'll work normally after that.

Oh yes, when you're done and feeling relieved, remember to check that you reconnected the little vent tube to the 12v battery, it leads out of the car through a little hole in the floor :)

[PeteB]

Whilst you can get it cheaper, and possibly higher capacity elsewhere, if you want an easy life I believe the current fixed price at a Toyota dealer for a new Battery on your model is £95 all in.

[Carltona123]

I changed my 12v Battery recently. There were no signs of problems but I did it as a precaution (car 12/07) as I was leaving the car at the airport over the Easter holiday. No way did I want to get stuck in Luton on my return. At over six years old I don't think it owed me much and it's now enjoying retirement sitting in my garage. Wish I could think of a use for it.

Anyway I investigated doing it myself but in the end, for not much extra money, I just let Toyota do it. And Pete's right - it was £95 total.

Hope you get yours sorted.

PS Not closing the boot properly can also cause the courtesy light to drain the Battery - I turned mine off altogether to be on the safe side.

[korat102]

I changed my 12v battery recently...Wish I could think of a use for it.

Keep it charged, With a little luck it'll be sufficient to start the Prius if you accidentally drain the Battery at home :)

Or...connect it to a solar charger and use it to provide LED lighting for your garage or garden...

Or..take it down the tip and get it recycled.

[Duffryn]

Had the same problem as the OP - except that the guilty party in my case was my 4 yr old granddaughter. Only had the car 2 months, and as it came with 1 years Toyota Roadside Assistance I phoned them and the AA arrived in exactly 36 minutes, on a Sunday too. He had the car started in 10 seconds. That was 15 months ago, and no further problems with Battery (yet).

[IanIanIanIan]

Take your old Battery to a scrapyard. I recently got £16 for two batteries. You will need photo ID these days but that is not a real problem.

[PeteB]

... my 4 yr old had left the interior light on, since Saturday night! So this morning, it won't start the engine. ...

Hi Rachael

Did you manage to start your car? Did it need a new Battery, or has the old one recovered?

Regards, PeteB

[PeteB]

I changed my 12v battery recently. ... At over six years old I don't think it owed me much ...

There's a certain amount of luck with batteries, I think, as well has how often and badly it's been abused.

When I bought my first Gen 1 Prius in 2002, the problem was not widely known, and many cars had duff 12v batteries by the time an owner bought the car brand new! The Gen 1 had a 35 ah Battery, and higher standing drain than either Gen 2 or 3. If everything was perfect, a fully charged Battery might have stood being parked for 3-4 weeks, we occasionally heard of 5.

The Gen 1 was never seriously marketed (we were sort of guinea pigs - and only 60 Toyota dealerships could handle them) and I doubt Toyota could have ramped up production much anyway (even the boot floor was a piece of plywood, with a layer of felt on top!). Most had completely flat batteries before they came off the ship, and several times again by the time the car was sold. My first one stopped holding enough charge overnight when it was under 2 years old. My second one had a new Battery at 9 months, but the replacement was still in the car when I sold it 9 years and 160,000 miles later!

The last 12v battery only got flattened once, when I parked it in one of those robotic car parks in London (you drive onto a sort of fork lift, get out [leaving car in neutral which meant leaving the key in[, and a machine takes the fork lift and deposits the car in a pigeon hole).

For some reason, in the Gen 1, just leaving the key in (not even on accessory position,) dramatically increased the drain the the 12v battery. I never heard why.

Anyway, the car park attendants got me going with a jump starter (I promptly bought one of those), and the drive home to Luton from Victoria Street, London recharged it sufficiently.

[Rach73]

... my 4 yr old had left the interior light on, since Saturday night! So this morning, it won't start the engine. ...

Hi Rachael

Did you manage to start your car? Did it need a new Battery, or has the old one recovered?

Regards, PeteB

Peteb. Yes thank you, I kept meaning to post to say it did! With the help of you guys and google I felt very empowered yesterday! The old one has recovered and seems ok, but I ordered a new one to be on the safe side. Last thing I want is to be caught out with my lo in tow! My clever brother in law will help me fit it! (Ie he'll fit it, I'll provide encouragement!)

I was amazed at how easily the car jumped! In my limited experience it's always been much more difficult!

Again I say, I love my Prius. And I love you all for helping me! X

[orangezorki]

Had the same problem as the OP - except that the guilty party in my case was my 4 yr old granddaughter. Only had the car 2 months, and as it came with 1 years Toyota Roadside Assistance I phoned them and the AA arrived in exactly 36 minutes, on a Sunday too. He had the car started in 10 seconds. That was 15 months ago, and no further problems with battery (yet).

There's a great deal of blaming 4 year olds going on here. Are you sure that you don't have something to tell us? Or am I just doing it wrong not having a 4 year old to blame everything on...

Source: My own previous adult stupidity.

David

[korat102]

I didn't have a scapegoat either. I just left the car nicely cosseted in the garage for a month and forgot about it. A few days before Christmas, I decided I needed it, pressed the unlock button on the keyfob and...nothing. The door locks were seized as well, having not been used for six years. After a few minutes of completely pointless messing about, I called the RAC. The bloke used a pair of pliers to rotate the key in the lock (while I held my breath). He then jump started it and had to be persuaded that everything was ok when the engine stopped after a few minutes - think it must have been his first hybrid. Anyway, I immediately bought new Battery and fitted it, I also bought a charger so I could keep it topped up when I wasn't using it, made a note in my diary to operate the door locks manually every month and had no further trouble.