Rx400h - Adjusting Hybrid Charging 'bias'?

[Neil Morphett]

Hi - have had my RX400h for a year now and I'm wondering whether a feature that I'm sure I saw on a test drive is still on the car.

In about 2004, maybe 2005, I went to a Lexus Open Day where the local dealers were demonstrating most of the range at a nearby country house. I was given an escorted test drive in the then new RX400h. I have a pretty solid memory that, as I was starting the test drive, the salesman commented that the (hybrid) Battery was a bit low (due to the amount of electric-drive demonstration that vehicle had been doing during the day), and adjusted something on the dash (maybe in the multimedia console, can't recall exactly) that he said would bias the hybrid system towards charging up the Battery a bit more than normal. Very faint memory that there were three settings...?

Since new I've averaged 29.6 mpg (peaked at 30.2 last summer) and I notice that, on long runs, the Battery is pretty much full and thus there's not much opportunity for achieving energy regeneration and consequently better economy. There are times I'd like the Battery to help more, in the knowledge that there's ample opportunity to charge it up again. However, I can't find any such adjustment in my car.

I've seen a couple of other threads about people wanting to force the car to start in electric drive mode; I guess this is related but more about adjusting the bias. Does anyone know about any such function? Or is my memory playing tricks?

Many thanks

[Mr Pants!]

Hey Neil,

I have not come across this before to be honest mate and I think i have pretty much clicked on every menu option in the car.

The only thing I can think of is that the salesman turned off everything, i.e. aircon, vents etc which will enable the engine to switch off quicker and demonstrate the hybrid drive. I have done that before with people when the Battery has been a bit low and someone who has not been in a hybrid before wants to see it pull away in silence, I quickly flick off anything that would cause the engine the run, aircon or heat (on a cold engine) will cause the engine to run initially.

The only item on the car that I am aware of that boosts the charge is the B select in the gear box, but looking at the other post on B option, it appears I may have been mis-informed.

[Neil Morphett]

Likewise - if it's a menu function it's got to be one of those cheat code functions we know and love (put gear stick in Park, hold trip button down, turn on sidelights three times whilst holding down passenger window switch, whistle in B-flat and SUDDENLY.... Aaaahhhhh). Quite why they hide functions in there rather than the on-screen I can't fathom.

I agree popping off the aircon would have encouraged the car to stay in electric mode a bit longer, but whatever he did was to tweak the car into charging up the Battery more, i.e. kick in petrol earlier. I'll book some hypnosis and see what comes out....