Rx400h Brake Fault

[MartynT]

Have just heard on news that Toyota have been advised of a potential problem on the Prius brakes, and an apparant "conflict" between the ABS and the braking regeneration system. By coincidence my RX400 with only 30,000 on the clock has just been checked over for a braking fault, and the symptoms were very similar to the prius - ie when braking on uneven or slippery surfaces, the braking system gets confused and braking power is lost momentarily. My dealer said they could find no fault, but strangely, after being checked and serviced, the fault disappeared! Hopefully not a cover up on the part of Lexus?? Any other RX owners experienced this?

[keywest]

Interesting. I sometimes experience a feeling when very lightly braking that the brakes start working then stop. A little more pressure then brings them on.

[Linehill]

I did experience jerky braking, especially on a downhill slope when on snow or ice. It seemed as though the ABS was locking on and off very quickly and the front wheels did lock up completely. Instant release on the brake pedal slopped any further slide.

On today's BBC news Toyota admit there is a software problem on KERS Battery recharge system on the Prius. I wonder if the RX 400h uses the same software? Anyone asked their dealer?

[MartynT]

[

[MartynT]

I did experience jerky braking, especially on a downhill slope when on snow or ice. It seemed as though the ABS was locking on and off very quickly and the front wheels did lock up completely. Instant release on the brake pedal slopped any further slide.

On today's BBC news Toyota admit there is a software problem on KERS battery recharge system on the Prius. I wonder if the RX 400h uses the same software? Anyone asked their dealer?

Interesting that - I found that this problem, and the one explained by Keywest have been evident for several weeks now - wonder if we have opened a can of worms here!!?

[ihpj]

Isn't the hybrid system carried forward across the entire range though? Definitelyworth asking around...

[neil_cooper_kemp]

I've experienced the effect described by keywest since new on my now 2.5 year-old RX400h. It feels to me as if the "engine braking" disengages when the brakes are applied (and seems to happen more often - but not only - when going downhill). I notice that the Battery regeneration stops at the moment I feel the slight decrease in brake-effectiveness.

I've often felt like mentioning it to my dealer, but never have. I always assumed I'd be told 'that's just a feature of the hybrid powertrain'.

Neil

[indy727]

i had a very similar issue just two weeks after owning my rx400h but due to the fact it was light snow at the time it was put down to conditions. There is definitely a slight "let go" when braking in mine. It would be interesting to see who else has experienced similar symptoms to what the latest hybrids are being recalled for?

[neil_cooper_kemp]

Good description indy727 - that's exactly what it is: a slight "let go". The car is still braking, just not as effectively as it was a moment before. It's never got me into bother, but on a few occasions it's taken me slightly closer to things than I wanted to be.

Just to expand on my earlier comment - I notice that the needle indicating power/regeneration pops up out of the blue regeneration sector and stays resolutely on 0 regardless of the current charging level of the Battery.

Neil

[mastertc]

Good description indy727 - that's exactly what it is: a slight "let go". The car is still braking, just not as effectively as it was a moment before. It's never got me into bother, but on a few occasions it's taken me slightly closer to things than I wanted to be.

Just to expand on my earlier comment - I notice that the needle indicating power/regeneration pops up out of the blue regeneration sector and stays resolutely on 0 regardless of the current charging level of the battery.

Neil

Found this update on the lexus site. Says NONE of the European Lexus range are affected by any of the recalls

http://www.lexus.co.uk/about/news-and-even...dal-recall.aspx

Good news!!!

[neil_cooper_kemp]

I'm not so sure it is good news.

Lexus UK/Europe are taking the view that because the European/UK models are different to the US models then there can't be a problem.

Just because the models are different it does not necessarily follow that there is no problem.

Neil

[lfoggy]

My 2007 RX400h is behaving completely normally with no discernable problems with the brakes. In the recent icy weather I was impressed with the traction control, four wheel drive and braking....

[daveyboo]

My 2007 RX400h is behaving completely normally with no discernable problems with the brakes. In the recent icy weather I was impressed with the traction control, four wheel drive and braking....

Yes the same for me, sometimes you can feel a little surge on braking but I have always put it down to the auto gearbox changing down.

[rhosneigr]

I don't think you will feel the the auto box changing down on the RX400 as the transmission is CVT which means continuous variable i.e no gearchanges.