Prius error message and starting problem

[rf4c]

Hi Everybody,

The subject is a Prius T-Spirit 2010

I’m hoping somebody here can help me progress with a problem
which is about to drive me insane.

I am suffering from constant Battery drain, requiring me to jump start the car
if I don’t drive it daily.

The problem is, I have a lung disease which makes things very miserable when I have
to jump start all the time. Sometimes, I’m so breathless, I simply abandon my trip.

I get the dreaded “P LOCK MALFUNCTION”  message. According to many opinions
on the internet, I have a dead Battery.

However, my Battery is brand new and is more than likely not dead when this problem arises,
because it triggers the door locks when I approach the car.

Two questions:
1. Do you think I have a battery drain and if so, where would the most likely place to look for it be?

2.    Failing a solution, is there any way I could wire up to the Positive terminal in the engine bay
        to bring it inside the car and also bring an earth point inside so that I could sit in the car and
    use my portable power pack to jump start?
If so, any advice on designing this?

It’s a big ask, but any advice very welcome.

Thanks so much in advance and kindest wishes to everybody

Jim

 

[Chippy01]

Most common power drain points are the internal lamps, if I remember correctly.

I would first make sure that these lamps (sunvisor and boot lamp comes to mind) are turned solidly off. Then I would check the connections on the 12volt Battery in the boot, just to make sure they are on nice and tight. I'd inspect the Battery poles for corrosion as well.

Apart from that, I guess the next step would be to get the ECU codes read to see if anything shows up there.

 

[Mike169]

Hi Jim.

Have you thought about going to a Battery type shop, Halfords being a good example, and get them to test your Battery as it just might be that your Battery is worn out, as they will fit a new one for you if that's what your car needs and the fitting by them is usually free from reputable stores.........good luck, Mike.

[rf4c]

Hi Guys,

Thanks so much for taking the time to reply.

I had the Battery tested and it's ok.  I also checked out the internal lamps.

I haven't got to the Battery terminals yet, but will try that in the next day or two.

I don't know if it means anything but two things came to mind.

I've had this problem for over a year now, and it started around the same time the inbuilt gps system decided not to pick up satellites anymore! Don't know if this is a factor.

 

Also when I tried starting the car a few days ago, it was dead, just getting the "P LOCK" message.

As soon as I started the car, I did the "Info" button and Headlights on/off trick to get to the menu for Battery information and it showed the battery pumping out 14Volts!!

Anyway guys, thanks so much again, and if anything esle comes to mind, please let me know.

Very good wishes

Jim

[PeteB]

Once the system is running (green READY lamp lit on dash), the Hybrid system is charging the 12V Battery so the voltage will always show around 14V even if the Battery is close to death.

The real test is to do it after the 12V Battery has been fully charged (after a longish drive), then do the trick with all the dash lights on (that is, from off, press Start without a foot on the brake so the READY indicator does not light, but lots of other warning lamps do).  Then you'd expect to see it drop rapidly towards 12V.  If it quickly goes below that, you've got a problem.

Not sure if the SatNav issue is linked, but I'd double check all the door are shut, manually turn off front and rear interior lights, and boot light, just in case any door/boot switches are not working as they should.  At the very least, see if any interior lights or boot light stay on with all doors and boot properly shut.

Another trick if you're not using the car much (and security isn't too much of a worry) is to not use the alarm.  This means the car won't be deadlocked either.  This can be achieved either by locking with the emergency key (be warned, it often feels like it's stuck and needs quite a bit of force) or lock the car with the drivers door open using the switch on the arm rest, then close the door while holding the outside handle as if you're trying to open the door, but make sure your keys are not inside!  This will reduce the drain on the 12V battery slightly.

[Gerg]

All the above answers give excellent suggestions and information.

As you've had this fault for so long already, if you are willing to spend another £28, perhaps this meter might help give some extra insight?

https://www.amazon.co.uk/UNI-T-UT210E-Current-Meters-Capacitance/dp/B00O1Q2HOQ

The price is now the cheapest it has been all year. The low price of this meter and accuracy of the DC current clamp caused a few surprises when it was tested by electronics hobbyists.

The current clamp allows you to measure what is going in and out of the Battery without having to disturb any connections.  You do need to be able to fit the clamp (about the size of your thumb and forefinger closed) around the Battery cable so that you can still see the digital display.

Obviously this means having the boot open, with all the problems that go with that.  But, if you insert a screwdriver at right angles to the boot lock ( I use a Philips no.2 point), you can operate the boot lock, so it moves to the 'closed' position.  You can now take your time seeing what happens to the Battery drain current at your leisure, and the car thinks the boot is shut. Perhaps remove fuses to the satnav etc. to see what happens to the current meter readings.

I have done this boot lock thing on our Auris (whilst checking some new reverse parking sensors); you are just simulating the boot catch with a screwdriver blade.

Don't forget to operate the boot lock before you try to slam the boot shut!

Afterwards, the meter could be re-boxed and given to a loved one as a Christmas present.

Just a thought.

[PeteB]

44 minutes ago, Gerg said:

...Obviously this means having the boot open, with all the problems that go with that...

nice unit - and if anyone with a Gen 4 wants to use one, the 12V Battery moved under the bonnet on this version, so even easier!

[Gerg]

Thinking about this some more, I would remove power to the satnav/radio unit as the next step.

As the satnav is not working, either the aerial has a bad connection, or the pcb has failed.

If it does have a pcb failure, could it not have failed in such a way that the unit fails to power down when commanded?

As well as draining power itself, a refusal to power down may prevent the main bus/network controller from shutting down, as presumably this can only go into standby when all other control units have gone into standby first.  Quite a bit of supposition here.

The draining Battery fault has a loose parallel with the early Mk2 Hybrid Auris 12v Battery drain problem, which I think turned out to be a defective hazard flasher switch preventing its controller from going into standby, and sometimes flattening the 12v Battery in a few days.

If your 12v battery is being repeatedly flattened it will soon wear it out, so as you progress (or otherwise) with this problem, the battery may need replacing again (warranty?).  More so if you haven't got the genuine replacement Yuasa battery, as the genuine (£120 - 180) part Is designed to suffer flattening with less damage than the ones that feature in other makers compatibility tables, says Yuasa UK Technical.

If the car hasn't been checked for logged fault codes yet, I would definitely get that done, although the flat battery event may throw up some of its own, so some experience at interpreting the codes would be of benefit.

HTH

[johalareewi]

16 hours ago, rf4c said:

I've had this problem for over a year now, and it started around the same time the inbuilt gps system decided not to pick up satellites anymore! Don't know if this is a factor.

Could be a fault in the head unit. There is a12V hot feed to the unit (even when everything is off) so in theory it could drain the Battery.  It is fairly easy to remove the head unit on a gen3 Prius so you could unplug it and see if that makes a difference.

Once the 12V Battery has been totally discharged and recharged a few times, it is not going to hold its charge for very long anyway.  Toyota do a fixed price 12V Battery fit (used to be £99).  Should be on their website somewhere.

 

 

[rf4c]

Hi everybody,

This is all fantastic stuff!!

Thank you so much, it’s is renewal of my faith in human nature to experience
such goodwill!

Thank you all!

It will take me quite a while to get through all of these suggestions.

As I mentioned, I suffer from a lung disease.
Just dressing in the morning can take 30 minutes followed by breathing exercises to recover!!
so attacking the Prius with my tools could take a while!!

I did manage to acquire a Toyota Tech manual showing me how to access all parts of the car,
so that will ease things a bit!

I promise I will report back in time, so others might get something beneficial!

I just wanted to comment on johalareewi’s post.

I’m originally from London but living in Ireland now, and his post makes me want to be back in London!

Toyota charging  fixed price for Battery replacement for £99 ! Even if the price has risen, I don’t think it
can match the price here in Ireland - last year it was 240 Euros,  (about £210)!!!!!

Thanks again everybody.

Very kind wishes to all

Jim

[Gerg]

Hi,

If you do get to do a current drain test, rather than remove a fuse to, or remove the satnav, then this link and video from Priuschat may be of use. It's 15 minutes long, so get a comfortable seat. The video is with the post from Mendel Leisk (post no.4):

https://priuschat.com/threads/overnight-draw.186993/

Using the meter I suggested in the earlier post would mean the warnings about overloading the meter etc. can be ignored, and you don't have to disconnect any cables either, but it is not essential to have that one  The key message from the video is, after all the electronic systems have shut themselves down, a current of 50 milliamps is the norm.

The Toyota fixed price battery replacement mentioned by johalareewi is now £120.

Could you get a Toyota dealer (from Northern Ireland?) to agree to post one to you if you find you need one again, so you can take advantage of the UK price (+ postage)?

HTH

[rf4c]

Hi Gerg,

that's a fabulous video! I'll definitely be trying that option! 

The Northern Ireland Battery purchase is a great idea too.  I actually imported the car from there so it's an easy solution.

I feel a bit silly that I didn't think of it before shedding £210!!

Thanks again for giving your time to me. I'm sincerely grateful.

Very kind wishes

Jim