Slight brake juddering

[Ala Larj]

Just got back from a trip round Scotland and noticed that when braking very gently or coming to a stop there seems to be a very slight juddering as if the abs is operating very slightly. It makes it difficult to come to a smooth stop. Is this normal and something to do with the regeneration thing?

I also had the tyre monitoring light come on. When I checked the pressures on the dash. None were showing. After I switched off and on again all was ok. Has anyone else experienced this?

Also, a couple of times the wipers sudden stopped wiping in mid sweep whilst in auto mode. As soon as I flipped the stalk down all seemed ok. Anything to worry about?

 

[rayaans]

43 minutes ago, Ala Larj said:

Just got back from a trip round Scotland and noticed that when braking very gently or coming to a stop there seems to be a very slight juddering as if the abs is operating very slightly. It makes it difficult to come to a smooth stop. Is this normal and something to do with the regeneration thing?

I also had the tyre monitoring light come on. When I checked the pressures on the dash. None were showing. After I switched off and on again all was ok. Has anyone else experienced this?

Also, a couple of times the wipers sudden stopped wiping in mid sweep whilst in auto mode. As soon as I flipped the stalk down all seemed ok. Anything to worry about?

 

That wiper behaviour is odd, I haven't had any vehicle where the wipers just stop mid sweep! Potential worry there and didn't you just have your screen changed?

The regenerative brakes do make it difficult to come to a smooth stop, yes, so perhaps its that but you could also have warped discs.

[Ala Larj]

Thanks Rayaan. Yes I did have the screen changed. Um, could be related. Am going to get Lexus to have a look at the brakes as it's still under warranty. Need a new tyre too as have a slow puncture! And the boot occasionally doesn't open fully. Hope I've not bought a lemon!

[olliesgrandad]

Yesterday my brakes exhibited the same pulsating symptoms at low speed in traffic. I experienced similar with my IS and am sure it's due to the energy regeneration. I take it that the puncture is not in the tread where it can be repaired 

[Ala Larj]

It's a really strange slow puncture. It didn't deflate at all whilst driving, only goes down over night!

[Ala Larj]

27 minutes ago, olliesgrandad said:

Yesterday my brakes exhibited the same pulsating symptoms at low speed in traffic. I experienced similar with my IS and am sure it's due to the energy regeneration. I take it that the puncture is not in the tread where it can be repaired 

The juddering only happens at slow speed or when lightly touching the brakes. In most normal driving it is not noticeable.

[NemesisUK]

Juddering as described is usually attributable to pad material deposited on the disc, or possibly due to corrosion. 

Try a couple of high speed hard stops (where safe to do so) and see if this clears the judder.

I've had no problem moderating the regen braking to give a smooth stop

[Ala Larj]

Will give that a go. Thanks.

[Ala Larj]

Update. Lexus looked at the brakes today and said that there is nothing wrong with the discs or pads and it probably is due to the regeneration system. I pointed out that the NX courtesy car didn't have the same problem. They are going to get another GS in and let me drive it to see if it is inherent in this model!

[NemesisUK]

Did you try the hard stops?

I get no 'judder' from the regen system on my hybrid. The only noise is a groan at the point of stopping and then only in slow stop-start traffic.

[Ala Larj]

Sorry forgot about the hard stops. Will try that when safe to do!

[Ala Larj]

Success. Thanks Peter, did four hardish slow downs from 60 and now nice and smooth.