Rx400H Electric Motor Running... At Rest?

[cduluk]

Hey guys,

I took this picture (at rest) the other day because i wanted to show my mom this ES350 (since she's in the market for a car) and i noticed that the "electric motor" indicator was ON in both the gauge cluster LCD and on the center console "Energy Monitor" of my Rx400h. This diagram usually appears when the electric motors are sending electricity to the wheels. I was in "drive" but completely stopped at rest, with my foot firmly on the brake pedal. I thought this was odd so i tried to make a note to look at the energy monitor when at rest at different dates, and it seems that 60% of the time, even at rest with my foot firmly on the brake pedal, the monitor indicates that the electric motor is sending power to the wheels. Sometimes, if i press the brake pedal even further, it will stop- but sometimes not. I've checked and there's no correlation between these events and the rear brake lights; meaning i could be on the brake pedal with the rear brake lights ON, and yet the energy monitor is sending e- to the wheels.

Has anyone else noticed this on the Rx400h? Seems strange to me... Thanks for any input!

[lemon]

I've noticed this before on mine, but every single time, pushing harder on the brake pedal makes it stop. I guess there's a point there where there's enough pressure on the brake pedal to hold the vehicle at a stop, but not enough for the computer to realize that no motive power is needed to the electric motors??

The ES350 is nice.. but tell Mom to get an IS, or better yet, the new GS.

[BobBass]

Occasionally I have to put more pressure on the brake pedal than expected to prevent the yellow lines from appearing on the display. But, I have always been able to "shut them off." Funny you should post this - seems like it's happened a little more in the last six months than I recall but it's still very rare. Mine is an '08 with 31K miles.

[lemon]

I've checked and there's no correlation between these events and the rear brake lights; meaning i could be on the brake pedal with the rear brake lights ON, and yet the energy monitor is sending e- to the wheels.

I don't think the brake light switch would have any control over when power is sent to the electric motors. I'm thinking it could be the stroke sensor, speed sensor, throttle position sensor, transmission range sensor etc. - likely some combination of all of that and more. In this particular case, since stepping harder on the brake pedal makes the power stop, maybe it's related to the stroke sensor in the brake pedal?

[maseace]

Your energy gauge on the far left shows 0. If it's using any power, it's not much.

[RX400h]

It could be that the powertrain management computer is simulating a non-hybrid vehicle's auto transmission in which there is always forward motion poer to the drive wheels without any movement of the gas pedal.

By the way, the ES350 hybrid was recently revealed at the New York auto show. Its fuel mileage should be quite impressive.

[cduluk]

I've checked and there's no correlation between these events and the rear brake lights; meaning i could be on the brake pedal with the rear brake lights ON, and yet the energy monitor is sending e- to the wheels.

I don't think the brake light switch would have any control over when power is sent to the electric motors. I'm thinking it could be the stroke sensor, speed sensor, throttle position sensor, transmission range sensor etc. - likely some combination of all of that and more. In this particular case, since stepping harder on the brake pedal makes the power stop, maybe it's related to the stroke sensor in the brake pedal?

It's funny you should mention that because I'm still having an issue with that "farting" noise when I depress the brake pedal all the way. It seems to happen more when the outside temperatures are low, but I'm not sure what's causing it. I wonder if these issues are related?

Do you guys think this is worth showing the dealer? If it's happening to some of you too then it might be "normal", but still, it's odd.

[riwyle]

I've checked and there's no correlation between these events and the rear brake lights; meaning i could be on the brake pedal with the rear brake lights ON, and yet the energy monitor is sending e- to the wheels.

I don't think the brake light switch would have any control over when power is sent to the electric motors. I'm thinking it could be the stroke sensor, speed sensor, throttle position sensor, transmission range sensor etc. - likely some combination of all of that and more. In this particular case, since stepping harder on the brake pedal makes the power stop, maybe it's related to the stroke sensor in the brake pedal?

It's funny you should mention that because I'm still having an issue with that "farting" noise when I depress the brake pedal all the way. It seems to happen more when the outside temperatures are low, but I'm not sure what's causing it. I wonder if these issues are related?

Do you guys think this is worth showing the dealer? If it's happening to some of you too then it might be "normal", but still, it's odd.

Had the same two years ago. There is a TSIB on it. Might be BR 003-07. Looking at the paper work, it appears they tried the bleeding procedure shown in BR003-07, were not successful, so they replaced the ABS actuator Assy . Have not had a problem since.

Here is a link http://us.lexusownersclub.com/forums/index.php?app=core&module=attach&section=attach&attach_id=12936

[aus_rx400h]

I've noticed this behavior on mine too on the odd occasions but it does go away when I put a bit firmer pressure on the brake pedal. Once the energy stopped, u can ease off the pressure.

[lemon]

I've checked and there's no correlation between these events and the rear brake lights; meaning i could be on the brake pedal with the rear brake lights ON, and yet the energy monitor is sending e- to the wheels.

I don't think the brake light switch would have any control over when power is sent to the electric motors. I'm thinking it could be the stroke sensor, speed sensor, throttle position sensor, transmission range sensor etc. - likely some combination of all of that and more. In this particular case, since stepping harder on the brake pedal makes the power stop, maybe it's related to the stroke sensor in the brake pedal?

It's funny you should mention that because I'm still having an issue with that "farting" noise when I depress the brake pedal all the way. It seems to happen more when the outside temperatures are low, but I'm not sure what's causing it. I wonder if these issues are related?

Do you guys think this is worth showing the dealer? If it's happening to some of you too then it might be "normal", but still, it's odd.

If you're still within warranty, the brake actuator TSB should be performed under warranty. I don't know if it has anything to do with the power to electric motor thing, but you might as well have it done if you're hearing that weird 'honking', 'squawking' noise.

[cduluk]

Dp

[cduluk]

Thankfully we have the Lexus extended warranty which expires in July 2013, I believe. I noticed that the TSB above is listed for the 06-07 RX400h- do you think this would apply to the 08? I could picture having to argue with my dealer about the year as they seem to be so clueless about these things LOL...

[Melchior]

On my '07 RX400h, it sometimes shows electric power going to the wheels when I'm at a stop with the brakes firmly depressed-- but ONLY when I'm on a STEEP uphill slope. I assume this is intended to minimize the roll-back when you take your foot off the brake pedal.