mckellyb

In pulling fuses/battery power from my 460 L yesterday, looking for the parasitic drain it has, when I went out later that day, the weird noise/feeling in the brake pedal is gone. Not lessened, not better, but gone. Stayed gone for the entire run of errands I had, which means at least six start/stop cycles.

After a week, we'll see...

Junglequac

Congrats amigo and may it put an end to it. Apologies for not seeing/following your prior issues with this, but did you ever get the ABS/VSC light? I ask as I just a few weeks ago had a new brake actuator put in by Lexus. Shockingly and somewhat worryingly, the PO had just had this done around 15,000 miles ago and had issues off the rip.

Since having it done, there has been a tremendous difference in low speed braking. In regards to smoothness and no trace of pulsation or the aforementioned feeling that something is amiss.

Doublebase

You pulled a fuse and fixed your brake problem? How can that be? Stuck relay or something? Maybe you released a bad relay in the circuit? Anyway good luck, let us know how it goes.

mckellyb

Never got the ABS/VSC light. The local dealer didn't believe it was the actuator, even though it did the weird feel/noise while at a stop in "P", and was infinitely repeatable. The "tech" kept trying to claim it was the pads/calipers and that said brakes on my Touring L didn't look original. I left after that particular line of BS.

Doublebase, I know, right? I'll believe it's better after a week of commuting. That week starts right now.

I don't even know which fuse it was, as I pulled every single one in the frontmost fuse box, underhood, looking for a parasitic drain.

mckellyb

Well, it's been a week, the noise/odd feel is still gone.

Junglequac

Yeah I don't like the idea of simply pulling a fuse on a car as complex as the 460 fixing what might be the brake actuator. If possible, I would go to another Lexus dealer if you are lucky enough to have more than one in your area.

I suppose out of sight, out of mind. Moreover, provided the ABS/VSC light did not go off, perhaps it is just that a parasitic drain. Regardless, I am glad it is working out for you and may this be the last of it!

mckellyb

Oh, I put all the fuses back. It's as if having no power for 30-45 minutes caused it to cold reboot whatever was making the weird, groaning pedal noise when you let off from a stop which also seemed to result in non-linear feel and a severe initial bite.

AKS

Can you tell us which fuse you pulled out?

mckellyb

See, that's the thing, I pulled out a slew of them, over the course of about 2 hours, but I think it's the one, underhood, labeled DC CUT 1.

mckellyb

Wait, what?!

I'm searching for the circuit which is the drain. Pulling the battery cable helps absolutely none in this search.

None.

I truly hope your post was supposed to be humor.

Junglequac

The electrohydraulic brakes are kinda funky. That said, when I first got mine, it too exhibited such symptoms and within 3 weeks of owning it the ABS/VSC lights went on (intermittently) which ended up giving cause for a new brake actuator. I believe the lights going off needs to happen in order for Lexus to replace the actuator as otherwise, you are talking a close to $4000 repair.

What is mildly disconcerting is that it had been replaced just 10,000 miles prior, but immediately the original owner lodged concerns which they chalked up to it needing new brakes.

All I can say is since having the actuator replaced, it has exhibited no trace of any of the above and honestly expect that to continue for some time.

roadfrog

LOL. My apologies, I misunderstood what you were doing. All I saw was, "I disconnected every fuse". I realize now that you were trying to find the source of current draw and not merely trying to "reset" a component.. I'll delete my previous post.

mckellyb

It was a very happily surprising bonus, in fact.

And it's now been a couple of weeks, but the brakes feel almost like regular old hydraulic ones.

droclex

​​​​​​Thanks for this thread. Dying to know which fuse got the job done. Anyway you could detail a little better what you did? Was it simply a matter of pulling every fuse and popping them back in while the car was off? Thanks again!

mckellyb

droclex...

I had it out the longest, probably a couple of hours.