IS300h. Dead as a dodo. Then boot trouble.

[Gearoidmuar]

Fob wouldn't open door. Removed key thing, opened door. No lights on anything. Googled and read manual.
When the 12V Battery is flat or dead, nothing works.
You can't push start a hybrid. You need to have second car and jump leads.
There's a big grey fusebox on right side of engine as you look from the front of the car. The plus terminal is in there covered by a red hinged plastic cover.
There are two sprung grips which you undo at back and towards front. Then there are  three plastic clip things which you need to wedge open with small flat screwdriver to lift cover up.

 

Wear rubber gloves just in case. Pull red cover up and clip the red positive jump lead on the terminal. Clip the other red positive on the Plus on second car. Then plug the black on the negative of the second car and finally the black on at bare metal part on the engine etc on the lexus. IF you've chosen the second black properly your lexus dash will light up.
Then start second car and rev up a little for 5 mins. Then leaving that running, press the Push on the lexus.. when the Ready light lights your're in business.
Now, unclip black lexus black second car, red second car and lastly red lexus. In that order. Leave lexus on and when everything restored go for a drive for a few miles. With a little luck you'll be fine. Bring jump leads with you just in case!
If the problem doesn't recur the Battery is okay. I'm sure mine is as the car was hardly used for weeks.

Second problem. Next day, couldn't open boot. From inside car or with fob.

Solution. When you open the glove compartment there's a boot release button on its right rim used to keep boot closed for extra security. I'd somehow pressed that during my various manoeuvres. Press that, end of problem.

This may be useful to someone.
The instructions on attaching and detaching jump leads are fairly obtuse in the manual. Reverse previous procedure... How can you keep that stuff in your head?


 

[royoftherovers]

Very thoughtful Garry.Many thanks.

[Herbie]

15 hours ago, Gearoidmuar said:

The instructions on attaching and detaching jump leads are fairly obtuse in the manual. Reverse previous procedure... How can you keep that stuff in your head?

The manual is inaccurate in a couple of respects and makes it much more hassle than it needs to be.

First of all, there's nothing magical or mysterious about jump starting any car, hybrid or conventional. All you are doing is supplementing one dodgy 12v source by piggybacking a good 12v source onto it and as long as you get red or + to red or +, and black or - to black or -, then that's basically it.

It doesn't matter electrically if you connect the jump leads directly to the Battery or if you use the jump start post in the engine bay fusebox, 12v is 12v and where it comes from matters not a jot. The only reason why you maybe should connect the negative cable to a bare metal part away from the Battery is that a charging Battery can give off Hydrogen gas and a spark as you disconnect the lead could ignite it and cause an explosion. However, in more than 45 years of driving and messing with jump leads I've never seen this happen in person, nor do I know anyone else who has ever seen it happen either.

The advice to have the donor car's engine running isn't strictly necessary either. It would be for a conventional car but not if the recipient car is a hybrid.

The reason for this is that a conventional car has a starter motor that will draw more than 300A when cranking the engine. Once the engine is running and the alternator is spinning, it's the alternator that supplies all of the car's electrical needs, so if the donor car's Battery wasn't up to the job then the recipient car will draw current from the donor alternator, hence why the engine needs to be running.

Our hybrids don't have starter motors (or alternators) so all that our 12v Battery has to do is to boot the computers and get the hybrid system up and running, a process that takes less than 20A, which is something that the donor Battery can quite easily supply on its own.

As an aside, a hybrid should never be used to jump start another car (unless it's also a hybrid) for similar reasons. Our cars don't have alternators so the 12v Battery is charged by means of a DC/DC converter, which takes power from the 288v traction Battery and steps it down to about 14.5v. Remember that a conventional starter motor can draw over 300A to crank the engine, so if our 12v Battery wasn't up to the job the recipient car would look to our equivalent of the alternator to provide it. Unfortunately, the DC/DC converters just can't supply that and there would most likely be a big bang and an escape of the magic smoke that makes the converter work, followed by a huge bill to replace it.

Instead of jump leads which need a second car to be present, I carry a jump start battery pack similar to this one in the glovebox. They work really well and are well worth it for peace of mind alone. I've also fitted a much more convenient way of connecting it too, should I ever need to do it, as you'll see in this topic I posted recently:

 

 

[Gearoidmuar]

Thanks Herbie. I'm no car expert at all. Bicycles and Photography are my thing. I suspected I didn't have to have the engine running.
Manuals of all types are just badly written! Trying to find things in manuals is even worse!
There's a chap called Brucie on a cycling forum I'm on and he's like you! A mine of information!

I'll store your wisdom on this.

 

[Hadrian]

To open the boot when locked, there's a key you can pull out of the key fob,  It fits into a keyway on the boot lid.

 

[Gearoidmuar]

I know how to take the key out of the fob and have done it several times, but I didn't know about this keyway. There is a button on the right inside rim of the glove compartment.  I'll check out this keyway..

[steve2006]

 

[Thackeray]

On 6/9/2020 at 9:20 PM, Gearoidmuar said:

Leave lexus on and when everything restored go for a drive for a few miles.

The big advantage of going for a drive is that you'll be able to enjoy driving your car again and have a pleasant outing.

But there isn't any extra benefit for the 12 volt Battery. This is because as soon as the car is in Ready state, the 12v Battery is being charged from the hybrid Battery. This happens whether the engine is running or not. The car doesn't have to be moving.

In conventional cars with an alternator, you may have the possible advantage that the alternator is spinning faster when you drive the car. This may charge the Battery more rapidly. But I have to say that when alternators began to replace dynamos in cars, their selling point, as I remember it, was that they had higher output at lower rotation speeds. Certainly, with a dynamo you got little output when the car was idling so you definitely needed to go for a drive. I don't know whether this was the case when alternators became the norm. Anyone know the answer?

[Hadrian]

11 hours ago, Gearoidmuar said:

I know how to take the key out of the fob and have done it several times, but I didn't know about this keyway. There is a button on the right inside rim of the glove compartment.  I'll check out this keyway..

It's on the underside of the boot lid. on the left hand side just above the end of the number plate.

[Gearoidmuar]

So it is! You're a star. When I rang the garage (A Lexus garage) they didn't know about this!
Thank you. Great info.

[royoftherovers]

9 minutes ago, Gearoidmuar said:

So it is! You're a star. When I rang the garage (A Lexus garage) they didn't know about this!
Thank you. Great info.

Treat the Manual as a Bible, Garry and turn to it in your hour of need.

[Hadrian]

13 hours ago, Gearoidmuar said:

So it is! You're a star. When I rang the garage (A Lexus garage) they didn't know about this!
Thank you. Great info.

I believe it's the same on all or most Lexus models.   A friend with a 450 told me about it.

It may well be in the manual, but it doesn't do any harm to ask. That's what forums are all about.