Herbie

Is the existing battery Lithium? If not, I wouldn't use a Lithium battery as a substitute. It's not an area that I have much knowledge of but I can forsee problems with the battery management and charging system if, for example, it's expecting to see a NiMH battery in there but it gets Lithium instead.

Yes. Lexus register the tracker to you so that it's on the tracker company books as it were. If you're unlucky enough to have the car stolen you then: Phone the police to report it stolen and get a crime reference number from them Phone the Tracker company and give them the crime number Tracker company then activate the device and it starts to transmit its location As far as I know, all police forces nationwide have tracker receivers in their traffic cars, so they go do what they do.

Some good observations and questions there Red. The problem is that, by its very nature, it's very difficult to make accurate comparisons because there are so many variables. Things like temperature, how many times it's been flattened, how long it was left in a discharged state etc., etc., will all take their toll on the battery. There is a good test that can show the state of the battery but you'd have to get the car home to do it, because to be accurate it needs to be charged up first. You'll need to buy a load tester or drop tester as they're sometimes known, like this one from Amazon. I'd stay away from the modern digital ones because they measure various parameters and then calculate what they think the result should be. They don't actually do a real load test at all and in my opinion, there's no substitute for a real test. So, charge the battery up using a proper charger (not a trickle charger), then run the drop test and the tester will indicate the true state of the battery.

NNNNNOOOOOO!!!!!!! Lexus voice control is abysmal and pathetic, but team voice control with Android Auto or Apple CarPlay and it's heaven on Earth. It's especially good if, like mine, your car doesn't have a touch screen and you have to use that silly mousey joystick thing. Me: "Hey Google - open Waze" AA/ACP: "Opening Waze" Me: "Hey Google - navigate to M33 4RX" Waze: "Navigating to M33 4RX - OK, let's go" No drama, no problems, works just as it's meant to, as does voice control with other apps than navigation.

I would have thought that the car would come with Android Auto and/or Apple Car Play already installed, or at the very least the dealer may have to activate it for you. Is that not the case?

I don't know how much parts would be at the dealers but there's no need to go there as there's plenty on eBay. This one for the electrical sensor or complete unit This one if it's the mechanical linkage that's gone

No worries Don

Yep, that's me and I forgive you. But, now that you know.... OK, yes, I agree, but what I meant was that it isn't a 'fixable' fault. It's a design flaw that never should have got off the drawing board 10 or more years ago and you only need to look at the debacle over the CANbus thefts to know that they won't do anything retrospectively to the cars out there that already have this flaw. Even if they were willing, I'm not sure they could; some of the battery boxes and battery locations are just so small with no room for a bigger battery anyway. The only things you can do are to (a) keep the car on a trickle charger, or (b) use it more often, or (c) just sit in it for an hour per week with it in READY mode, as per Lexus' own instructions during Covid lockdown.

I'm actually saying the exact opposite. What I'm saying is that even conventional cars with battery capacities of 100Ah or more will eventually suffer from a flat 12V battery if left long enough and/or only used for short or infrequent runs. All cars have a quiescent current draw from the battery to keep alive such things as the radio presets, the seat memory, the clock and so on. Even though these are small demands totalling anywhere from about 50 to 100mA, they will eventually flatten the battery. It's just more noticeable and more inconvenient in hybrids because they only have very small batteries anyway. I have no intention of "ending" the post as it's not mine to end. My, my, you are a spitty little bunny this morning The LBX apparently has a battery with a 31Ah capacity, which means you've got 18.41 days from fully charged to fully discharged at a draw of 70mA. If you could physically fit a 100Ah battery in there you would have 59.52 days and nobody would be complaining because they wouldn't see that as a problem. By the way, I think my RX has a 45Ah battery so you're right, it doesn't suffer as badly as the LBX - but it still does suffer if I leave it long enough.

Look, once and for all, it's not a Lexus (or other manufacturer) problem, it's a matter of simple physics, and no matter how much you may want to, not even you can defeat the laws of physics. Small batteries don't hold charge for long. Larger batteries hold charge for longer. Lexus made a decision a long time ago to use small batteries and it really is as simple as that. They could change their rationale and make future cars with bigger batteries but (a) I very much doubt they will, and (b) that wouldn't help the owners of thousands of cars driving around now.

Well done Don. The usual problem is getting something that physically fits in the battery box and has the terminals the right way round. I take it that the one on the right is the original at 35Ah and you've upgraded to 45Ah? If so, that gives you an extra 5.92 days (from 20.83 days @35Ah to 26.75 days @45Ah) before it goes flat if not used or charged - caveats further up this thread still apply though. How I wish we could get something with an absolute minimum of 75Ah or better still, 100Ah. Sadly, nothing like that will ever fit in the battery box of my RX so I've got my trusty jump start battery pack in the car at all times.

Sadly, it is what it is and Lexus aren't going to do anything about it. It's not ideal but the fact is you know about it now and can take steps to mitigate the situation. I think we've come full circle now though, haven't we, regarding prospective owners doing some research to see if a hybrid fits their needs and driving habits before signing on the dotted line? If you knew then what you know now, would you still buy the car? Genuine question, not trying to be obnoxious, just curious.

Most of these third-party units such as the Grom Vline 2, the Lexion, the Lsailt and others will now allow you to choose which side is the driver's seat and the screen can be manipulated accordingly, such as navi closest to driver (2/3 screen) with info to the other side (1/3 screen) or vice versa, or navi full screen.

When I had my 3RX I installed a jump start socket in the centre console and kept the battery pack itself in either the glove box or under a seat, and had no problems regarding heat in the cabin at all.

Unfortunately that was probably just wasted time and did nothing for the battery, because that's not how you use a trickle charger. If the battery was as flat as it sounds then it needed to be put on a proper charger capable of supplying about 5A or more, for an overnight charge at the very least. Personally I'd probably give it a full 24-hour charge. When initially connected the charger will squirt out 5A but as the battery gets more and more charged, the output of the charger will regulate itself down to about 1.0A or whatever. Big punch of power at the beginning of the process, dropping very low at the end. The maximum output of a trickle charger is somewhere around 1.5A and the idea is that once the battery is fully charged (using a proper charger) you then connect the trickle charger and leave it connected 24/7 until you need to use the car again. Although the output of a trickle charger is very low, it's higher than what would be leaving the battery so the net result is that the battery doesn't lose charge.

The only reason that hybrids don't have alternators is that an alternator is driven by a belt attached to the petrol engine. As we know, in a hybrid the petrol engine doesn't run all the time so an alternator would be as much use as a chocolate fireguard. Same with other things like the aircon compressor and the power steering pump. Imagine being halfway through a hard turn and the hybrid system decided to turn off the petrol engine, resulting in sudden and unexpected loss of steering assistance.

Sorry Elaine, I've just re-read your post and realised that you have indeed already bought the battery monitor. Now that you know from the user manual just how little power it takes itself (1.0mA or to put it another way, 0.01 of an Amp) you can go back and have it fitted. Used in conjunction with the chart I hope you'll have much more confidence in the car.

I think it's possible but only for newer cars than yours, ie, 2020 onwards. You'll probably need a third-party solution like I did. Some to look at would be: Grom Vline 2 from gromaudio.co.uk Lexion https://lexionautomotive.com/pages/rapid-search-results?q=lexus BeatSonic RoadTop GTA Car Kits

Way further back than that I'm afraid. Mine's a 2018 and has the same problem and it may even go back as far as about 2010. I remember that someone replied to a previous post of yours, telling you of the Ancel BM300 battery monitor, so one of those along with this chart should help to alleviate your fears: If you don't want to buy the battery monitor then you can still refer to the chart but use a voltmeter that plugs into the car cig lighter/power point such as one of these As for the Lexus guy telling you that the battery monitor would drain the battery quickly, that's just completely wrong. You can see from the screenshot below that it takes an average of 1.0mA to power it. When the car isn't being used the 'standing' current draw for gadgets such as the radio presets, the clock and so on is around 50 to 70mA, perhaps even more, depending on how much stuff needs to be kept alive. I'm sure you'll agree that an extra 1.0mA is just not going to cause any problems.

In my 2018 RX, behind the glove box, there's a chunky wiring harness that comes through the bulkhead and it's protected by a rubber grommet. I made a little hole in the grommet and got my wire through there.

News to me as well.

BRILLIANT!!!!!! Well done Nicky, that truly is great news

Each time the battery goes flat it sustains some damage and loses some capacity, so it reduces what is already a small battery even further. Just as an example so these figures won't be correct but we'll say that it's 100% charged. If/when it goes flat it'll be slightly damaged so it won't accept any more than 95%, even though the charger will think it's 100%. If it happens again, next time it may drop to 90% and so on until it finally dies. It sounds very much like your AA man is correct and the battery is fubar. If it was me, I'd put it on a proper battery charger for an overnight charge, maybe even a full 24-hour charge. Then you need to have it load tested, preferrably with a proper drop tester something like this one. The modern electronic ones look at various parameters and show a reading that it thinks it should be. They're alright but there's no substitute for a proper drop test using a proper load.

Not to belittle your efforts but there really is no need whatsoever to go to those lengths to make the -ve lead reach. First of all, forget any talk of an "official" negative connection. The neg battery post is connected directly to the car body, so the entire car is effectively the negative battery post. Any* nut, screw, bolt or bracket that is clean and unpainted (very important) and has a good connection to the body will do the job. That is literally any nut, screw, bolt or bracket that has a good connection with the metalwork, whether that be at the front, back, top or bottom of the car. * Just beware that some screws will be terminated in moulded plastic brackets/fitments that may not be immediately obvious, so they're no good for this purpose; neither are shock absorber top bolts, in general. In the photo below the yellow arrows point to suitable places to connect the black lead to - but with the caveat that I don't have an LBX and it's much easier to be there looking into the engine bay than looking at a photo. So don't shoot the messenger if I have one or two out of place

Each time the battery goes flat it sustains some damage, so the first thing I'd suggest is to put it on a proper battery charger for an overnight charge, maybe even a full 24-hour charge. Then you need to have it load tested, preferrably with a proper drop tester something like this one. The modern electronic ones look at various parameters and show a reading that it thinks it should be. They're alright but there's no substitute for a proper drop test using a proper load.