Lexus 300H March 2014

[fergie]

Broke down twice in one week, the AA 'jumped it off', via the fuse box underneath the bonnet which apparently is the correct way, they couldn't check the Battery as he didn't know were it was located.

Driver's leather seat has not enough lumber support for my partner, he tried a mesh seat support and a cushion to no avail, he then bought a thick support pillow which to date seems to be working, without this he suffers with severe back pains, even though he had no problems with his old Toyota Carina or his current 7 year old Avensis.

Managing to get 49mpg at best, thats driving very carefully, Lexus have offered to buy it back at £26,000, its only done 2,700 miles, it would be a loss of almost £7,000, too much to lose.

[rayaans]

Broke down twice in one week, the AA 'jumped it off', via the fuse box underneath the bonnet which apparently is the correct way, they couldn't check the battery as he didn't know were it was located.

Driver's leather seat has not enough lumber support for my partner, he tried a mesh seat support and a cushion to no avail, he then bought a thick support pillow which to date seems to be working, without this he suffers with severe back pains, even though he had no problems with his old Toyota Carina or his current 7 year old Avensis.

Managing to get 49mpg at best, thats driving very carefully, Lexus have offered to buy it back at £26,000, its only done 2,700 miles, it would be a loss of almost £7,000, too much to lose.

Broke down as in how? Engine failed or Battery gone? Back pain means one of two things, either there is something wrong with the seat or the seat position has not been set properly for your partner. I recently had the same feeling in a CT200h which has "too much" lumbar support. I changed the position of the seat and no more back pain.

If you provide more details on how old your car is, what trim and options you have on the car we may be able to help you further.

All cars tend to do less MPG than the dealers quote, simply because when tested, the cars are taped up at the seams and have overinflated tyres. A couple of methods you could try is to inflate the tyres, swap tyres out for better fuel efficiency rated tyres and try braking slower and earlier and accelerating slower. It should help somewhat. It can be done as whatcar got 56mpg on their F Sport after a session with a fleet trainer.

[LiCkWiD]

Broke down twice in one week, the AA 'jumped it off', via the fuse box underneath the bonnet which apparently is the correct way, they couldn't check the battery as he didn't know were it was located.

Driver's leather seat has not enough lumber support for my partner, he tried a mesh seat support and a cushion to no avail, he then bought a thick support pillow which to date seems to be working, without this he suffers with severe back pains, even though he had no problems with his old Toyota Carina or his current 7 year old Avensis.

Managing to get 49mpg at best, thats driving very carefully, Lexus have offered to buy it back at £26,000, its only done 2,700 miles, it would be a loss of almost £7,000, too much to lose.

Ouch.. sorry to hear this. Not exactly the kind of story you, or at least I, associate with Lexus.

But honestly, a 7 year old Avensis offers more support than the Lexus? Wow! I'd love to see the interior of that Avensis :)

I feel for you on the MPG front. I was able to get to 60 on the way back from Bolton, last week. That's a 260 mile drive.. so I was happy to see my previous best of 53 shattered.

Rayaans is totally correct... getting good MPG out of these cars took a total change in driving style for me.

Out of interest, are most of your miles B road, A road, motorway? Or a mix, perhaps?

[fergie]

Hi, Avensis we have had from new, interior is immaculate, car had only done 50,000 miles.

My Lexus has never been on a motorway, lot of village driving at 30 mph on EV mode mostly B roads, so never been over 65 mph.

Maybe this is the problem??

[fergie]

Both times the Battery was flat.

Silver, grey leather trim, Sat Nav

[Steve44]

Both times the battery was flat.

Silver, grey leather trim, Sat Nav

Which one? 12v normal car Battery, or the hybrid traction Battery? I suspect the former.

[rayaans]

Both times the battery was flat.

Silver, grey leather trim, Sat Nav

If the Battery is flat, it could be that the Battery is faulty. Get them to change it under warranty. It may also be that something has been kept on in the car overnight.

[DJP]

I notice you say most of the mileage has been in EV mode. I might be wrong, but thought I'd read somewhere in the manual it wasn't recommended to use EV mode all the time. I wonder if the car Battery has been working overtime making sure the hybrid batteries remains above 20%, and this is what has LED to the flat Battery. Just a thought.

I think running in Eco is the suggested route to maximise fuel efficiency, the price for which is a modest reduction in power. Personally I'm quite happy to run around in Normal apart from the odd occasion when I can drive in Sport and actually give the car a bit of a push.

[Steve44]

If the car exhausts the Battery in EV mode, it will disengage it and start the engine automatically. Car brain won't let it drop to less than 20%.

Car is like any normal, non hybrid car though,without a functioning 12v Battery it won't work.

Personally I think it is the normal 12v car Battery which is flat, possibly faulty. Fergie should take it back to the dealer and ask them to check the Battery condition, as it is entirely possible it is faulty from new.

[DJP]

If the car exhausts the battery in EV mode, it will disengage it and start the engine automatically. Car brain won't let it drop to less than 20%.

Car is like any normal, non hybrid car though,without a functioning 12v battery it won't work.

Personally I think it is the normal 12v car battery which is flat, possibly faulty. Fergie should take it back to the dealer and ask them to check the battery condition, as it is entirely possible it is faulty from new.

I agree it's defo the car Battery, as you say the car won't let the hybrid Battery drop below 20% (or go over 80% either), but could the car Battery be being asked to do too much itself and going flat? Or it could just be faulty of course lol.

[ColinBarber]

excessively forcing the use of EV mode using the button will normally lead to a decrease in mpg compared to letting the car do its own thing. You will raise the temperatures of the Battery and motors which may limit their use when it would be most efficient for them to be used and you will force the engine to come on when it may not be needed and recharge the Battery, instead of efficiently recharging during normal use. There are exceptions but best just to use EV to move the car a few meters off a driveway without having the engine start.

[Steve44]

+1

Also lots of stop/start and short journeys are murder on a normal engine and car Battery charging circuit, especially if it is new, as it never gets the chance to properly recharge. Maybe the best bet would be to try an extended run up the motorway. Something more than 20miles?

[ColinBarber]

Also lots of stop/start and short journeys are murder on a normal engine and car battery charging circuit, especially if it is new, as it never gets the chance to properly recharge. Maybe the best bet would be to try an extended run up the motorway. Something more than 20miles?

On a Toyota/Lexus hybrid the aux Battery (12v) is charged whenever the car is in a 'ready' state, it is recharged from the hybrid Battery and inverter not the engine/alternator as with a conventional car (it doesn't even have an alternator). Technically is doesn't matter how long you drive it, just the amount of time the ignition is on and in ready.

[fergie]

To put all your minds at ease went to Lexus, the earth lead was off, they put it back on, tightened it, been alright since.

[Steve44]

Ah, OK. So if the hybrid Battery is permanently depleted (by driving in EV mode all the time say on short journeys), how does it charge the car Battery? Does it just run the engine to drive the generator? Does the car not have an alternator at all then just the hybrid generator?

[DJP]

To put all your minds at ease went to Lexus, the earth lead was off, they put it back on, tightened it, been alright since.

Excellent news, and oh so simple!

[ColinBarber]

Ah, OK. So if the hybrid battery is permanently depleted (by driving in EV mode all the time say on short journeys), how does it charge the car battery? Does it just run the engine to drive the generator? Does the car not have an alternator at all then just the hybrid generator?

Yes it will force on the engine to drive the generator, which will recharge the hybrid Battery and provide all power to the systems.

Correct, the car has no alternator or starter motor. The 12v Battery just provides power until the system becomes 'ready'. Starting and charging is all done by the hybrid generator/motor.

[Silver Arrow]

Seats are very much a personal thing. I didn't find the F Sport seats to my liking at all - no matter the adjustment....there are very few cars I can drive comfortably :-(

It can be debilitating to say the least....